GAS TURBINE OPERATION

Abstract

A gas turbine engine (10) for an aircraft is revealed.The gas turbine engine comprises: a combustion chamber (16) comprising a combustion chamber (120) and a plurality of fuel spray nozzles (124) configured to inject fuel into the combustion chamber (120), wherein the plurality of fuel spray nozzles (124) comprises a first subset (124A) of fuel spray nozzles (124) and a second subset (124B) of fuel spray nozzles (124), wherein the combustion chamber (16) is operable in a state in which each of the fuel spray nozzles of the first subset (124A) of fuel spray nozzles (124) is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset (124B) of fuel spray nozzles (124), wherein the number of fuel spray nozzles (124) in the first subset (124A) of fuel spray nozzles (124) is a ratio of the number of fuel spray nozzles (124) in the second subset (124B). The subset (124B) of the fuel spray nozzles (124) is in the range of 1:3 to 1:6.A thrust-nvPM emission index ratio is defined as follows: . EI max TOF max TOEIL free running FL free running where: EI Leerlauf The nvPM emission index of the gas turbine engine (10), corrected for system losses, in mg / kg at operation with approximately 7% of the available thrust under given operating conditions, is; EI maxTO the nvPM emission index in mg / kg of the gas turbine engine (10), corrected for system losses, at operation with approximately 100% of the available thrust under the given operating conditions; F maxTO the thrust of the gas turbine engine (10) at approximately 100% of the available thrust in kN under the given operating conditions is and F idleThe thrust of the gas turbine engine (10) is approximately 7% of the available thrust in kN under the given operating conditions. The thrust-to-nvPM emission index ratio is greater than 0.02. The gas turbine engine (10) is configured to supply the multiple fuel spray nozzles (124) with a fuel that includes sustainable aviation fuel (SAF). Methods for operating the gas turbine engine are also disclosed.

Description

AREA

[0001] The present disclosure relates to emissions of non-volatile particulate matter (nvPM) from gas turbine engines, in particular gas turbine engines for an aircraft. The present disclosure provides various methods for operating a gas turbine engine and gas turbine engines. In particular, the present application relates to methods for operating gas turbine engines using a fuel comprising a sustainable aviation fuel (SAF) and to gas turbine engines configured for operation with a fuel comprising an SAF. BACKGROUND

[0002] The aviation industry is expected to see a shift towards the use of fuels that differ from the currently widely used conventional kerosene-based jet fuels.

[0003] The inventors have determined that the emissions of a gas turbine engine are significantly dependent on the fuel used, in particular that the amount of nvPM generated by the engine varies depending on the operating parameters and the type of fuel used. Therefore, there is a need to consider the fuel properties of these other fuels and to adapt methods for operating gas turbine engines accordingly. SUMMARY

[0004] According to a first aspect, a gas turbine engine is provided for an aircraft, which includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A first nvPM emission index ratio idle to MTO (maximum take-off) is defined as follows: EILeerlaufEImaxTO where: EGG Leerlauf the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions; and EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; the first nvPM emission index ratio idle to MTO of the gas turbine engine is less than 3; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0005] A reduced nvPM content in the exhaust gas of a gas turbine engine advantageously contributes to a reduction in the engine's undesirable emissions. For example, depending on the operating conditions, such a reduction in nvPM can lead to a reduction in soot deposits within and / or downstream of the combustion chamber and / or to an improvement in local air quality. Furthermore, in certain phases of an aircraft flight (in which contrail formation would otherwise be expected), a reduction in the nvPM content in the exhaust gas can lead to a reduced intensity of contrails and / or a shorter time to contrail dissipation. It has also been recognized that specific parts of the flight cycle in which the nvPM value is reduced (or most significantly reduced) can be targeted to achieve a desired outcome, for example, with regard to environmental impact.By way of example, a lower nvPM value under cruise flight conditions can particularly reduce the impact of radiative forcing of contrails. Also by way of example, a lower nvPM value under idle conditions can particularly improve local air quality at ground level in the engine operating area. Again by way of example, a lower nvPM value under MTO conditions can particularly reduce the maximum nvPM production rate during the flight cycle and / or improve air quality at ground level and / or in the engine operating area. These considerations can apply to all aspects of the disclosure.

[0006] It has been established that when certain types of fuel, such as sustainable aviation fuel, are burned, a number of parameters related to the operation of a gas turbine engine affect, or are a significant factor in, the configuration and arrangement of the engine's combustion chamber. Accordingly, one or more parameters of the following aspects may be advantageously considered when determining, for example, operating settings, the combustion chamber arrangement, and / or the combustion chamber configuration, in order to influence and / or optimize how this fuel is distributed, ignited, and / or burned in the gas turbine engine. These considerations can apply to all aspects of the disclosure.

[0007] The first nvPM emission index ratio idle to MTO of the gas turbine engine can be greater than zero.

[0008] The first nvPM emission index ratio idle to MTO can be less than 2.54 and preferably less than 2.33 and more preferably less than 2.12.

[0009] The first nvPM emission index ratio idle to MTO can be less than or equal to 1.5, and can preferably be less than or equal to 1, and can more preferably be less than or equal to 0.5.

[0010] The first nvPM emission index ratio idle to MTO can be less than or equal to 0.377 and can preferably be less than or equal to 0.346 and can more preferably be less than or equal to 0.314.

[0011] The first nvPM emission index ratio idle to MTO can be less than or equal to 0.319 and can preferably be less than or equal to 0.293 and can more preferably be less than or equal to 0.266.

[0012] The first nvPM emission index ratio idle to MTO can be greater than or equal to 0.184 and can preferably be greater than or equal to 0.207 and can more preferably be greater than or equal to 0.23.

[0013] The first nvPM emission index ratio idle to MTO can be greater than or equal to 0.212 and can preferably be greater than or equal to 0.239 and can more preferably be greater than or equal to 0.265.

[0014] The first nvPM emission index ratio idle to MTO can be in the range of 0.184 to 0.377 and can preferably be in the range of 0.207 to 0.346 and can more preferably be in the range of 0.230 to 0.314.

[0015] The first nvPM emission index ratio idle to MTO can be in the range of 0.212 to 0.319 and can preferably be in the range of 0.239 to 0.293 and can more preferably be in the range of 0.265 to 0.266.

[0016] The first nvPM emission index ratio (idle to MTO) can be less than 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.377 or in any range between two of these values.

[0017] A second nvPM emission index ratio, idle to MTO, can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, and if a fuel supplied to the combustion chamber includes a sustainable aviation fuel; EGG maxTO,SAFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if a fuel supplied to the combustion chamber includes a sustainable aviation fuel, is; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; EGG maxTO,FFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; and The second nvPM emission index ratio, idle to MTO of the gas turbine engine, can be less than 1.

[0018] The second nvPM emission index ratio, idle to MTO, can be greater than zero.

[0019] The second nvPM emission index ratio, idle to MTO, can be less than or equal to 0.8, and preferably less than or equal to 0.6, and more preferably less than or equal to 0.4.

[0020] The second nvPM emission index ratio, idle to MTO, can be less than or equal to 0.178, and preferably less than or equal to 0.164, and more preferably less than or equal to 0.149.

[0021] The second nvPM emission index ratio, idle to MTO, can be greater than or equal to 0.03, and preferably greater than or equal to 0.06, and more preferably greater than or equal to 0.09.

[0022] The second nvPM emission index ratio, idle to MTO, can be greater than or equal to 0.118, and preferably greater than or equal to 0.133, and more preferably greater than or equal to 0.148.

[0023] The second nvPM emission index ratio, idle to MTO, can be in the range of 0.118 to 0.178, and preferably in the range of 0.133 to 0.164, and more preferably in the range of 0.148 to 0.149.

[0024] The second nvPM emission index ratio, idle to MTO, can be less than 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95 or 1, or lie within any range defined by any two of these values.

[0025] The second nvPM emission index ratio, idle to MTO, of the gas turbine engine can be 0.118, 0.12, 0.125, 0.13, 0.135, 0.14, 0.145, 0.15, 0.155, 0.16, 0.165, 0.17, 0.175, 0.178, or lie within any range defined by any two of these values.

[0026] According to a second aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A second nvPM emission index ratio, idle to MTO, is defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions and if a fuel supplied to the combustion chamber includes a sustainable aviation fuel; El maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if a fuel supplied to the combustion chamber includes a sustainable aviation fuel, is; EGG Leerlauf,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; the second nvPM emission index ratio idle to MTO of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0027] The second nvPM emission index ratio idle to MTO defined in the second aspect can be defined in the context of the first aspect as above.

[0028] According to a third aspect, a method for operating the gas turbine engine of the first aspect or the second aspect is provided, wherein the method includes supplying fuel comprising a sustainable aviation fuel to the plurality of fuel spray nozzles.

[0029] According to a fourth aspect, a method for operating a gas turbine engine is provided, which includes the gas turbine engine: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A first nvPM emission index ratio of idle to MTO (maximum take-off) can be defined as follows: EILeerlaufEImaxTO where: EGG Leerlauf the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions; and EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg at operation with approximately 100% of the available thrust under the given operating conditions; and the first nvPM emission index ratio idle to MTO of the gas turbine engine is less than 3; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0030] The first nvPM emission index ratio idle to MTO can be defined as above in connection with the first aspect.

[0031] A second nvPM emission index ratio, idle to MTO, can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, and if a fuel supplied to the combustion chamber includes a sustainable aviation fuel; El maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if a fuel supplied to the combustion chamber includes a sustainable aviation fuel, is; EGG Leerlauf,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; and wherein The second nvPM emission index ratio, idle to MTO of the gas turbine engine, can be less than 1.

[0032] The second nvPM emission index ratio, idle to MTO, can be defined as above in connection with the first aspect.

[0033] According to a fifth point, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A second nvPM emission index ratio, idle to MTO, can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions and if a fuel supplied to the combustion chamber includes a sustainable aviation fuel; El maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if a fuel supplied to the combustion chamber includes a sustainable aviation fuel, is; EGG Leerlauf,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; the second nvPM emission index ratio idle to MTO of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0034] The second nvPM emission index ratio, idle to MTO, can be defined as above in connection with the first aspect.

[0035] According to a sixth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A fuel flow-nvPM emission index ratio can be defined as follows: EILidle×Wf,IdleEImaxTO×Wf,maxTO where: EGG Leerlauf The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 7% of the available thrust under given operating conditions; EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; W f,Leerlauf the fuel flow rate to the fuel spray nozzles in kg / s is approximately 7% of the available thrust under the given operating conditions; and W f,maxTO the fuel flow rate to the fuel spray nozzles in kg / s at approximately 100% of the available thrust under the given operating conditions; the fuel flow-nvPM emission index ratio of the gas turbine engine is less than 0.3; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0036] The fuel flow nvPM emission index ratio can be less than 0.241 and preferably less than 0.221 and more preferably less than 0.201.

[0037] The fuel flow nvPM emission index ratio can be less than or equal to 0.15, can preferably be less than or equal to 0.1, and can more preferably be less than or equal to 0.05.

[0038] The fuel flow nvPM emission index ratio can be less than or equal to 0.0357, can preferably be less than or equal to 0.0327, and can more preferably be less than or equal to 0.0297.

[0039] The fuel flow nvPM emission index ratio can be less than or equal to 0.0285, can preferably be less than or equal to 0.0261, and can more preferably be less than or equal to 0.0238.

[0040] The fuel flow nvPM emission index ratio can be greater than or equal to 0.0138, can preferably be greater than or equal to 0.0156, and can more preferably be greater than or equal to 0.0173.

[0041] The fuel flow nvPM emission index ratio can be greater than or equal to 0.0189, can preferably be greater than or equal to 0.0213, and can more preferably be greater than or equal to 0.0237.

[0042] The fuel flow nvPM emission index ratio can be in the range of 0.0138 to 0.0357, and preferably in the range of 0.0156 to 0.0327, and even more preferably in the range of 0.0173 to 0.0297.

[0043] The fuel flow nvPM emission index ratio can be in the range of 0.0189 to 0.0285, and preferably in the range of 0.0213 to 0.0261, and even more preferably in the range of 0.0237 to 0.0238.

[0044] The fuel flow NVPM emissions index ratio can be less than 0.003, 0.004, 0.005, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.245, 0.35, 0.357 or a range between any two of these Values.

[0045] W f,Leerlauf can be in the range of 0.142 to 0.263 kg / s and can preferably be in the range of 0.160 to 0.241 kg / s and can more preferably be in the range of 0.178 to 0.219 kg / s.

[0046] W f,maxTOcan be in the range of 1.50 to 3.36 kg / s and can preferably be in the range of 1.69 to 3.08 kg / s and can more preferably be in the range of 1.88 to 2.80 kg / s.

[0047] According to a seventh aspect, a method for operating the gas turbine engine of the sixth aspect is provided, the method comprising the provision of fuel comprising a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0048] According to an eighth aspect, a method for operating a gas turbine engine is provided, wherein the gas turbine engine comprises: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A fuel flow-nvPM emission index ratio can be defined as follows: EILidle×Wf,IdleEImaxTO×Wf,maxTO where: EGG Leerlauf The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 7% of the available thrust under given operating conditions; EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; W f,Leerlauf the fuel flow rate to the fuel spray nozzles in kg / s is approximately 7% of the available thrust under the given operating conditions; and W f,maxTO the fuel flow rate to the fuel spray nozzles in kg / s at approximately 100% of the available thrust under the given operating conditions; and the fuel flow-nvPM emission index ratio of the gas turbine engine is less than 0.3; and the process involves supplying fuel comprising a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0049] Each of the fuel flow nvPM emission index ratios, W f,Leerlauf and W f,max,TO can be defined as above in connection with the sixth aspect. According to a ninth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A thrust-nvPM emission index ratio can be defined as follows: EImaxTOEImaxTOIIdle EIIdle where: EGG Leerlauf The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 7% of the available thrust under given operating conditions; EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; F maxTO the thrust of the gas turbine engine is approximately 100% of the available thrust in kN under the given operating conditions; and F Leerlauf The thrust of the gas turbine engine is approximately 7% of the available thrust in kN under the given operating conditions; the thrust-nvPM emission index ratio is greater than 0.02; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0050] The thrust-nvPM emission index ratio can be greater than 0.0264 and preferably greater than 0.0297 and more preferably greater than 0.033.

[0051] The thrust-nvPM emission index ratio can be greater than 0.0312 and preferably greater than 0.0351 and more preferably greater than 0.039.

[0052] The thrust-nvPM emission index ratio can be greater than or equal to 0.07, can preferably be greater than or equal to 0.1, and can more preferably be greater than or equal to 0.13.

[0053] The thrust-nvPM emission index ratio can be greater than or equal to 0.178, can preferably be greater than or equal to 0.2, and can more preferably be greater than or equal to 0.223.

[0054] The thrust-nvPM emission index ratio can be greater than or equal to 0.21, can preferably be greater than or equal to 0.237, and can more preferably be greater than or equal to 0.263.

[0055] The thrust-nvPM emission index ratio can be less than or equal to 0.365, can preferably be less than or equal to 0.335, and can more preferably be less than or equal to 0.304.

[0056] The thrust-nvPM emission index ratio can be less than or equal to 0.317, can preferably be less than or equal to 0.29, and can more preferably be less than or equal to 0.264.

[0057] The thrust-nvPM emission index ratio can be in the range of 0.178 to 0.365, and preferably in the range of 0.200 to 0.335, and more preferably in the range of 0.223 to 0.304.

[0058] The thrust-nvPM emission index ratio can be in the range of 0.210 to 0.317, and preferably in the range of 0.237 to 0.290, and more preferably in the range of 0.263 to 0.264.

[0059] The thrust-nvPM emission index ratio can be greater than 0.02, 0.04, 0.06, 0.08, 0.1, 0.12, 0.14, 0.16, 0.18, 0.2, 0.22, 0.24, 0.26, 0.28, 0.3, 0.32, 0.34, 0.36, 0.38, 0.4 or within any range defined by any two of these values.

[0060] The thrust-nvPM emission index ratio can be 0.178, 0.18, 0.2, 0.22, 0.24, 0.26, 0.28, 0.3, 0.32, 0.34, 0.36, 0.365 or lie within any range defined by any two of these values.

[0061] F maxTO can be in the range of 204 kN to 420 kN and preferably in the range of 229 kN to 385 kN and preferably in the range of 255 kN to 350 kN.

[0062] F Leerlauf can be in the range of 14.2 kN to 29.4 kN and preferably in the range of 16.0 kN to 26.9 kN and preferably in the range of 17.8 kN to 24.5 kN.

[0063] According to a tenth aspect, a method for operating the gas turbine engine of the ninth aspect is provided, the method comprising the provision of fuel comprising a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0064] According to an eleventh aspect, a method for operating a gas turbine engine is provided, wherein the gas turbine engine comprises: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A thrust-nvPM emission index ratio can be defined as follows: EImaxTOEImaxTOIIdle EIIdle where: EGG Leerlauf the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions; and EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; F maxTO The thrust of the gas turbine engine at approximately 100% of the available thrust in kN under the given operating conditions is, F Leerlauf The thrust of the gas turbine engine is approximately 7% of the available thrust in kN under the given operating conditions; and the thrust-nvPM emission index ratio is greater than 0.02; and the process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0065] Each of the thrust-nvPM emission index ratios, F maxTO and F Leerlauf can be defined as in connection with the ninth aspect.

[0066] According to a twelfth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: An nvPM emission index ratio for lean-burn cruise flight to MTO can be defined as follows: EIReiseflug(meier)EImaxTOBPR where: EGG Reiseflug (mager) which can be defined as follows: EImaxTO+EISteigflug2 El maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 100% of the available thrust under the given operating conditions; EGG Steigflug The nvPM emission index of the gas turbine engine, corrected for system losses, is in mg / kg when operating at approximately 85% of the available thrust under the given operating conditions; and BPR is the bypass ratio of the gas turbine engine; the nvPM emission index ratio of lean-burn cruise to MTO is less than 0.2; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0067] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.151, preferably less than 0.138 and more preferably less than 0.126.

[0068] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.136, preferably less than 0.125 and more preferably perhaps less than 0.114.

[0069] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.131, preferably less than or equal to 0.12 and more preferably less than or equal to 0.109.

[0070] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.118, preferably less than or equal to 0.108 and more preferably less than or equal to 0.098.

[0071] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.0751, preferably greater than or equal to 0.0845 and more preferably greater than or equal to 0.0938.

[0072] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.0869, preferably greater than or equal to 0.0977 and more preferably greater than or equal to 0.108.

[0073] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0751 to 0.131, preferably in the range of 0.0845 to 0.120 and more preferably in the range of 0.0938 to 0.109.

[0074] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0751 to 0.118, preferably in the range of 0.0845 to 0.108 and more preferably in the range of 0.0938 to 0.0980.

[0075] The nvPM emission index ratio for lean-burn cruise to MTO can be in the range of 0.0869 to 0.131, preferably in the range of 0.0977 to 0.120 and more preferably in the range of 0.108 to 0.109.

[0076] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.098, 0.11, 0.115, 0.12, 0.125, 0.13, 0.135, 0.14, 0.145, 0.15, 0.155, 0.16, 0.165, 0.17, 0.175, 0.18, 0.185, 0.19, 0.195 or 0.2, or lie within any range defined by any two of these values.

[0077] The nvPM emission index ratio for lean-burn cruise flight can be 0.0751, 0.08, 0.085, 0.09, 0.095, 0.1, 0.105, 0.11, 0.115, 0.12, 0.125, 0.13, 0.131 or lie within any range defined by any two of these values.

[0078] An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIReiseflug(fett)EImaxTOBPR where: EGG Reiseflug(fett) which can be defined as follows: EI climb + EI approach 2 EGG Steigflug the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions or under other operating conditions; EGG Anflug The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug is calculated; and EGG maxTO The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug is calculated; and where The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.3.

[0079] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.29, preferably less than 0.266 and more preferably less than 0.242.

[0080] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.285, preferably less than 0.261 and more preferably less than 0.237.

[0081] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.2, preferably less than or equal to 0.16 and more preferably less than or equal to 0.12.

[0082] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.105, preferably less than or equal to 0.0963 and more preferably less than or equal to 0.0875.

[0083] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.102, preferably less than or equal to 0.0926 and more preferably less than or equal to 0.0842.

[0084] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.0509, preferably greater than or equal to 0.0573 and more preferably greater than or equal to 0.0637.

[0085] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.0699, preferably greater than or equal to 0.0787 and more preferably greater than or equal to 0.0874.

[0086] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be in the range of 0.0509 to 0.105, preferably in the range of 0.0573 to 0.0963 and more preferably in the range of 0.0637 to 0.0875.

[0087] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be in the range of 0.0509 to 0.102, preferably in the range of 0.0573 to 0.0926 and more preferably in the range of 0.0637 to 0.0842.

[0088] The nvPM emission index ratio for cruise flight with rich combustion to MTO can be in the range of 0.0699 to 0.105, preferably in the range of 0.0787 to 0.0963 and more preferably in the range of 0.0874 to 0.0875.

[0089] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.3, 0.28, 0.26, 0.24, 0.22, 0.2, 0.18, 0.16, 0.14, 0.12, 0.1, 0.0842 or lie within any range defined by any two of these values.

[0090] The nvPM emission index ratio for cruise flight with rich combustion can be 0.0509, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095, 0.1, 0.105 or lie within any range defined by any two of these values.

[0091] The BPR can be in the range of 6.38 to 11.3 and more, preferably in the range of 7.18 to 10.4 and even more preferably in the range of 7.98 to 9.40.

[0092] The BPR can be in the range of 6.38 to 9.59 and more, preferably in the range of 7.18 to 8.79 and even more preferably in the range of 7.98 to 7.99.

[0093] The BPR can be in the range of 6.85 to 11.3 and more, preferably in the range of 7.70 to 10.4 and even more preferably in the range of 8.56 to 9.40.

[0094] According to a thirteenth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIReiseflug(fett)EImaxTOBPR where: EGG Reiseflug(fett) which can be defined as follows: EI climb + EI approach 2 EGG Steigflug The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 85% of the available thrust under the given operating conditions; EGG Anflug The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug is calculated; and EGG maxTO The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug is calculated; and the nvPM emission index ratio of cruise flight with rich combustion to MTO is less than 0.3; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0095] The nvPM emission index ratio of cruise flight with rich combustion to MTO and to or the BPR can be defined as above in connection with the twelfth aspect.

[0096] According to a fourteenth aspect, a method for operating the gas turbine engine of the twelfth or thirteenth aspect is provided, the method comprising the provision of fuel comprising a sustainable aviation fuel to the plurality of fuel spray nozzles.

[0097] According to a fifteenth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: An nvPM emission index ratio for lean-burn cruise flight to MTO can be defined as follows: EIReiseflug(meier)EImaxTOBPR where: EGG Reiseflug (mager) which can be defined as follows: EImaxTO+EISteigflug2 EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 100% of the available thrust under the given operating conditions; EGG Steigflug the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 85% of available thrust under the given operating conditions; and BPR is the bypass ratio of the gas turbine engine; and the nvPM emission index ratio of lean-burn cruise to MTO is less than 0.2; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0098] The nvPM emission index ratio for lean-burn cruise flight to MTO and to or the BPR can be defined as above in connection with the twelfth aspect.

[0099] An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIReiseflug(fett)EImaxTOBPR where: EGG Reiseflug(fett) which can be defined as follows: EI climb + EI approach 2 EGG Steigflug the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions or under other operating conditions; EGG Anflug The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug is calculated; EGGmaxTO The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug is calculated; and where The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.3.

[0100] The nvPM emission index ratio of cruise flight with rich combustion to MTO and to or the BPR can be defined as above in connection with the twelfth aspect.

[0101] According to a sixteenth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIReiseflug(fett)EImaxTOBPR where: EGG Reiseflug(fett) which can be defined as follows: EI climb + EI approach 2 EGG Steigflug The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 85% of the available thrust under the given operating conditions; EGG Anflug The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug is calculated; EGG maxTO The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug is calculated; and the nvPM emission index ratio of cruise flight with rich combustion to MTO is less than 0.3; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0102] The nvPM emission index ratio of cruise flight with rich combustion to MTO and to or the BPR can be defined as above in connection with the twelfth aspect.

[0103] According to a seventeenth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: An MTO-nvPM emission index ratio can be defined as follows: EImaxTO,SAFEImaxTO,FF where: EGGmaxTO,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that includes sustainable aviation fuel (SAF); and EGG maxTO,FF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 100% of the available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; the MTO-nvPM emission index ratio of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0104] The MTO-nvPM emission index ratio can be greater than zero.

[0105] The MTO-nvPM emission index ratio can be less than or equal to 0.93, can preferably be less than or equal to 0.86, and can more preferably be less than or equal to 0.79.

[0106] The MTO-nvPM emission index ratio can be less than or equal to 0.776, can preferably be less than or equal to 0.711, and can more preferably be less than or equal to 0.646.

[0107] The MTO-nvPM emission index ratio can be greater than or equal to 0.15, can preferably be greater than or equal to 0.3, and can more preferably be greater than or equal to 0.45.

[0108] The MTO-nvPM emission index ratio can be greater than or equal to 0.516, can preferably be greater than or equal to 0.581, and can more preferably be greater than or equal to 0.645.

[0109] The MTO-nvPM emission index ratio can be in the range of 0.516 to 0.776, and preferably in the range of 0.581 to 0.711, and more preferably in the range of 0.645 to 0.646.

[0110] The MTO-nvPM emission index ratio of the gas turbine engine can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0111] The MTO-nvPM emission index ratio can be 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.6, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.68, 0.69, 0.7, 0.71, 0.72, 0.73, 0.74, 0.75, 0.76, 0.77, 0.78, 0.79 or 0.8, or lie within any range defined by any two of these values.

[0112] A climb-nvPM emission index ratio can be defined as follows: ICE Climb, SAFE ICE Climb, FF where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; and where the climb-nvPM emission index ratio of the gas turbine engine may be less than 1.

[0113] The climb-nvPM emission index ratio can be greater than zero.

[0114] The climb-nvPM emission index ratio can be less than or equal to 0.9, can preferably be less than or equal to 0.75, and can more preferably be less than or equal to 0.6.

[0115] The climb-nvPM emission index ratio can be less than or equal to 0.57, can preferably be less than or equal to 0.523, and can more preferably be less than or equal to 0.475.

[0116] The climb-nvPM emission index ratio can be greater than or equal to 0.1, can preferably be greater than or equal to 0.2, and can more preferably be greater than or equal to 0.3.

[0117] The climb-nvPM emission index ratio can be greater than or equal to 0.379, can preferably be greater than or equal to 0.427, and can more preferably be greater than or equal to 0.474.

[0118] The climb-nvPM emission index ratio can be in the range of 0.379 to 0.570, and preferably in the range of 0.427 to 0.523, and more preferably in the range of 0.474 to 0.475.

[0119] More generally, the climb-nvPM emission index ratio of the gas turbine engine can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or lie within any range defined by any two of these values.

[0120] The climb-nvPM emission index ratio can be 0.37, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.6 or within any range defined by any two of these values.

[0121] An approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEI approach, FF where: EGG Anflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Anflug,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 30% of available thrust under the same given operating conditions as those under which EI Anflug,SAF is calculated, and if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel; and where the approach nvPM emission index ratio of the gas turbine engine may be less than 1.

[0122] The approach-nvPM emission index ratio can be greater than zero.

[0123] The approach nvPM emission index ratio can be less than or equal to 0.8, can preferably be less than or equal to 0.5, and can more preferably be less than or equal to 0.2.

[0124] The approach nvPM emission index ratio can be less than or equal to 0.185, can preferably be less than or equal to 0.169, and can more preferably be less than or equal to 0.154.

[0125] The approach-nvPM emission index ratio can be greater than or equal to 0.03, can preferably be greater than or equal to 0.06, and can more preferably be greater than or equal to 0.09.

[0126] The approach-nvPM emission index ratio can be greater than or equal to 0.122, can preferably be greater than or equal to 0.138, and can more preferably be greater than or equal to 0.153.

[0127] The approach-nvPM emission index ratio can be in the range of 0.122 to 0.185, and preferably in the range of 0.138 to 0.169, and more preferably in the range of 0.153 to 0.154.

[0128] More generally, the approach nvPM emission index ratio of the gas turbine engine can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0129] The approach-nvPM emission index ratio can be 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2 or within any range defined by any two of these values.

[0130] An idle-nvPM emission index ratio can be defined as follows: EILEerlauf,SAFEILeerlauf,FF where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under the given operating conditions or under other given operating conditions, and if a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and. if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; and where the idle nvPM emission index ratio of the gas turbine engine may be less than 1;

[0131] The idle-nvPM emission index ratio can be greater than zero.

[0132] The idle nvPM emission index ratio can be less than or equal to 0.8, can preferably be less than or equal to 0.5, and can more preferably be less than or equal to 0.2.

[0133] The idle nvPM emission index ratio can be less than or equal to 0.115, can preferably be less than or equal to 0.106, and can more preferably be less than or equal to 0.0959.

[0134] The idle-nvPM emission index ratio can be greater than or equal to 0.02, can preferably be greater than or equal to 0.04, and can more preferably be greater than or equal to 0.06.

[0135] The idle nvPM emission index ratio can be greater than or equal to 0.0766, can preferably be greater than or equal to 0.0862, and can more preferably be greater than or equal to 0.0958.

[0136] The idle-nvPM emission index ratio can be in the range of 0.0766 to 0.115, and preferably in the range of 0.0862 to 0.106, and more preferably in the range of 0.0958 to 0.0959.

[0137] The idle-nvPM emission index ratio can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0138] The idle-nvPM emission index ratio can be 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.52, 0.53, 0.54, 0.55 or in any range between any two of these values.

[0139] According to an eighteenth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A climb-to-emissions index ratio can be defined as follows: ICE Climb, SAFE ICE Climb, FF where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; and the climb-to-nvPM emission index ratio of the gas turbine engine may be less than 1; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0140] The climb-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0141] According to a nineteenth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: An approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEI approach, FF where: EGGAnflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Anflug,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 30% of available thrust under the same given operating conditions as those under which EI Anflug,SAF is calculated, and if one of the fuels supplied by the multitude of fuel spray nozzles is a fossil-based hydrocarbon fuel, then; and the approach-nvPM emission index ratio of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0142] The approach-nvPM emission index ratio can be defined as above in connection with the seventeenth aspect.

[0143] According to a twentieth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: An idle-nvPM emission index ratio can be defined as follows: EILEerlauf,SAFEILeerlauf,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, and if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and. if the fuel supplied to any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel, then; and the idle nvPM emission index ratio of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0144] The idle-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0145] According to a twenty-first aspect, a method for operating the gas turbine engine of any one of the seventeenth, eighteenth, nineteenth or twentieth aspects is provided, the method comprising the provision of fuel comprising a sustainable aviation fuel to the plurality of fuel spray nozzles.

[0146] According to a twenty-second aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and An MTO-nvPM emission index ratio can be defined as follows: EImaxTO,SAFEImaxTO,FF where: EGG maxTO,SAFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, when one of the The fuel supplied by a variety of fuel spray nozzles includes a sustainable aviation fuel (SAF); and EI maxTO,FF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies a fossil-based hydrocarbon fuel; and the MTO-nvPM emission index ratio of the gas turbine engine (10) is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0147] The MTO-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0148] A climb-nvPM emission index ratio can be defined as follows: ICE Climb, SAFE ICE Climb, FF where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAFis calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; and wherein The climb-nvPM emission index ratio of the gas turbine engine may be less than 1.

[0149] The climb-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0150] An approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEI approach, FF where: EGG Anflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGGAnflug,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 30% of available thrust under the same given operating conditions as those under which EI Anflug,SAF is calculated, and if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel; and wherein The approach nvPM emission index ratio of the gas turbine engine may be less than 1.

[0151] The approach-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0152] An idle-nvPM emission index ratio can be defined as follows: EILEerlauf,SAFEILeerlauf,FF where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under the given operating conditions or under other given operating conditions, and if a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and. if one of the fuels supplied to the multitude of fuel spray nozzles is a fossil-based hydrocarbon fuel, is; and wherein the idle nvPM emission index ratio of the gas turbine engine may be less than 1;

[0153] The idle-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0154] According to a twenty-third aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: A climb-to-emissions index ratio can be defined as follows: ICE Climb, SAFE ICE Climb, FF where: EGGSteigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under given operating conditions, where the fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; the climb-to-nvPM emission index ratio of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0155] The climb-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0156] According to a twenty-fourth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: An approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEI approach, FF where: EGG Anflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Anflug,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 30% of available thrust under the same given operating conditions as those under which EI Anflug,SAF is calculated, and if one of the fuels supplied by the multitude of fuel spray nozzles is a fossil-based hydrocarbon fuel, then; and the approach-nvPM emission index ratio of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0157] The approach-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0158] According to a twenty-fifth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: An idle-nvPM emission index ratio can be defined as follows: EILEerlauf,SAFEILeerlauf,FF where: EGGLeerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, and if a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, it is; and the idle nvPM emission index ratio of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0159] The idle-nvPM emission index ratio can be defined as in connection with the seventeenth aspect.

[0160] According to a twenty-sixth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and where: A fuel stream modified with respect to the MTO-nvPM emission index ratio can be defined as follows: EImaxTO,SAFEImaxTO,FF×Wf,maxTO where: EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that includes sustainable aviation fuel (SAF); EGG maxTO,FF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies a fossil-based hydrocarbon fuel; and W f,maxTOthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 100% of the available thrust under the given operating conditions; the fuel flow of the gas turbine engine, modified with respect to the MTO-nvPM emission index ratio, is less than 4 kg / s; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0161] The fuel flow in kg / s, modified with respect to the MTO-nvPM emission index ratio, can be greater than zero.

[0162] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than 3.36, more preferably less than 3.08 and even more preferably less than 2.8.

[0163] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be greater than or equal to 0.974, more preferably greater than or equal to 1.09 and even more preferably greater than or equal to 1.21.

[0164] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than or equal to 2.17, more preferably less than or equal to 1.99 and even more preferably less than or equal to 1.81.

[0165] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 0.974 to 2.17, preferably in the range of 1.09 to 1.99 and more preferably in the range of 1.21 to 1.81.

[0166] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than 2.95, more preferably less than 2.7 and even more preferably less than 2.46.

[0167] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be greater than or equal to 1.26, more preferably greater than or equal to 1.42 and even more preferably greater than or equal to 1.58.

[0168] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than or equal to 1.91, more preferably less than or equal to 1.75 and even more preferably less than or equal to 1.59.

[0169] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.26 to 1.91, preferably in the range of 1.42 to 1.75 and more preferably in the range of 1.58 to 1.59.

[0170] The fuel flow in kg / s modified with respect to the MTO-nvPM emission index ratio can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.974, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.17 or in any range between any two of these values.

[0171] W f,maxTO can be in the range of 1.50 to 3.36 kg / s and can preferably be in the range of 1.69 to 3.08 kg / s and can more preferably be in the range of 1.88 to 2.80 kg / s.

[0172] W f,maxTO can be in the range of 1.96 to 2.95 kg / s and can preferably be in the range of 2.20 to 2.70 kg / s and can more preferably be in the range of 2.45 to 2.46 kg / s.

[0173] A fuel flow modified with respect to the climb-nvPM emission index ratio can be defined as follows: EISclimb,SAFEISclimb,FF×Wf,climb where: EGG Steigflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Steigflugthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 85% of the available thrust under the same operating conditions as those in which EI Steigflug,SAF and egg Steigflug,FF calculated; and where the fuel flow of the gas turbine engine, modified with respect to the climb-nvPM emission index ratio, can be less than 3 kg / s.

[0174] The fuel flow in kg / s modified with respect to the climb-nvPM emission index ratio can be greater than zero.

[0175] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than 2.73, more preferably less than 2.5 and even more preferably less than 2.27.

[0176] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be greater than or equal to 0.589, more preferably greater than or equal to 0.663 and even more preferably greater than or equal to 0.737.

[0177] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than or equal to 1.3, more preferably less than or equal to 1.19 and even more preferably less than or equal to 1.08.

[0178] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.589 to 1.30, preferably in the range of 0.663 to 1.19 and more preferably in the range of 0.737 to 1.08.

[0179] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than 2.42, more preferably less than 2.21 and even more preferably less than 2.01.

[0180] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be greater than or equal to 0.763, more preferably greater than or equal to 0.858 and even more preferably greater than or equal to 0.953.

[0181] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than or equal to 1.15, more preferably less than or equal to 1.05 and even more preferably less than or equal to 0.954.

[0182] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.763 to 1.15, preferably in the range of 0.858 to 1.05 and more preferably in the range of 0.953 to 0.954.

[0183] The fuel flow in kg / s modified with respect to the climb-nvPM emission index ratio can be less than or equal to 0.589, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3 or any range between any two of these values.

[0184] W f,Steigflug can be in the range of 1.24 to 2.73 kg / s and can preferably be in the range of 1.39 to 2.50 kg / s and can more preferably be in the range of 1.55 to 2.27 kg / s.

[0185] W f,Steigflug can be in the range of 1.60 to 2.42 kg / s and can preferably be in the range of 1.80 to 2.21 kg / s and can more preferably be in the range of 2.00 to 2.01 kg / s.

[0186] A fuel flow modified with respect to the approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEIA approach, FF×Wf, approach where: EGG Anflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Anflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Anflugthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 30% of the available thrust under the same operating conditions as those in which EI Anflug,SAF and egg Anflug,FF to be calculated; and where the fuel flow of the gas turbine engine, modified with respect to the approach nvPM emission index ratio, is less than 0.9 kg / s;

[0187] The fuel flow in kg / s, modified with respect to the approach-nvPM emission index ratio, can be greater than zero.

[0188] The fuel flow in kg / s modified with respect to the approach-nvPM emission index ratio can be less than 0.841, more preferably less than 0.771 and even more preferably less than 0.701.

[0189] The fuel flow in kg / s modified with respect to the approach-nvPM emission index ratio can be greater than or equal to 0.0636, more preferably greater than or equal to 0.0716 and even more preferably greater than or equal to 0.0795.

[0190] The fuel flow in kg / s modified with respect to the approach-nvPM emission index ratio can be less than or equal to 0.13, more preferably less than or equal to 0.119 and even more preferably less than or equal to 0.108.

[0191] The fuel flow rate in kg / s, modified with respect to the approach-nvPM emission index ratio, can be in the range of 0.0636 to 0.130, preferably in the range of 0.0716 to 0.119 and more preferably in the range of 0.0795 to 0.108.

[0192] The fuel flow in kg / s modified with respect to the approach-nvPM emission index ratio can be less than 0.771, more preferably less than 0.707 and even more preferably less than 0.642.

[0193] The fuel flow in kg / s modified with respect to the approach-nvPM emission index ratio can be greater than or equal to 0.0788, more preferably greater than or equal to 0.0887 and even more preferably greater than or equal to 0.0986.

[0194] The fuel flow in kg / s modified with respect to the approach-nvPM emission index ratio can be less than or equal to 0.119, more preferably less than or equal to 0.109 and even more preferably less than or equal to 0.0987.

[0195] The fuel flow rate in kg / s, modified with respect to the approach-nvPM emission index ratio, can be in the range of 0.0788 to 0.119, preferably in the range of 0.0887 to 0.109 and more preferably in the range of 0.0986 to 0.0987.

[0196] The fuel flow in kg / s modified with respect to the approach nvPM emission index ratio can be less than or equal to 0.0636, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095, 0.1, 0.105, 0.12, 0.125, 0.13 or any range between any two of these values.

[0197] W f,Anflug can be in the range of 0.414 to 0.841 kg / s and can preferably be in the range of 0.466 to 0.771 kg / s and can more preferably be in the range of 0.517 to 0.701 kg / s.

[0198] W f,Anflug can be in the range of 0.513 to 0.771 kg / s and can preferably be in the range of 0.577 to 0.707 kg / s and can more preferably be in the range of 0.641 to 0.642 kg / s.

[0199] A fuel flow modified with respect to the idle-nvPM emission index ratio can be defined as follows: Idle run, safe idle run, FF×Wf, idle where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Leerlaufthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 7% of the available thrust under the same operating conditions as those in which EI Leerlauf,SAF and egg Leerlauf,FF to be calculated; and where The fuel flow rate of the gas turbine engine, modified with respect to the idle-nvPM emission index ratio, can be less than 0.3 kg / s.

[0200] The fuel flow rate in kg / s, modified with respect to the idle-nvPM emission index ratio, can be greater than zero.

[0201] The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be less than 0.263, more preferably less than 0.241 and even more preferably less than 0.219.

[0202] The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be greater than or equal to 0.0136, more preferably greater than or equal to 0.0153 and even more preferably greater than or equal to 0.017.

[0203] The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be less than or equal to 0.0252, more preferably less than or equal to 0.0231 and even more preferably less than or equal to 0.021.

[0204] The fuel flow rate modified with respect to the idle-nvPM emission index ratio, in kg / s, can be in the range of 0.0136 to 0.0252, preferably in the range of 0.0153 to 0.0231, and more preferably in the range of 0.0170 to 0.0210. The fuel flow rate modified with respect to the idle-nvPM emission index ratio, in kg / s, can be less than 0.263, more preferably less than 0.241, and even more preferably less than 0.219.

[0205] The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be greater than or equal to 0.0167, more preferably greater than or equal to 0.0188 and even more preferably greater than or equal to 0.0209.

[0206] The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be less than or equal to 0.0252, more preferably less than or equal to 0.0231 and even more preferably less than or equal to 0.021.

[0207] The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be in the range of 0.0167 to 0.0252, preferably in the range of 0.0188 to 0.0231, and more preferably in the range of 0.0209 to 0.0210. The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be less than 0.253, more preferably less than 0.232, and even more preferably less than 0.211.

[0208] The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be greater than or equal to 0.0136, more preferably greater than or equal to 0.0153 and even more preferably greater than or equal to 0.017.

[0209] The fuel flow rate in kg / s modified with respect to the idle-nvPM emission index ratio can be less than or equal to 0.0243, more preferably less than or equal to 0.0223 and even more preferably less than or equal to 0.0202.

[0210] The fuel flow rate modified with respect to the idle-nvPM emission index ratio, in kg / s, can be in the range of 0.0136 to 0.0243, preferably in the range of 0.0153 to 0.0223, and more preferably in the range of 0.0170 to 0.0202. The fuel flow rate modified with respect to the idle-nvPM emission index ratio, in kg / s, can be less than or equal to 0.0136, 0.014, 0.015, 0.016, 0.017, 0.018, 0.019, 0.02, 0.021, 0.022, 0.023, 0.024, 0.025, 0.0252, or any range between any two of these values.

[0211] W f,Leerlauf can be in the range of 0.142 to 0.263 kg / s and can preferably be in the range of 0.160 to 0.241 kg / s and can more preferably be in the range of 0.178 to 0.219 kg / s.

[0212] W f,Leerlauf can be in the range of 0.142 to 0.253 kg / s and can preferably be in the range of 0.160 to 0.232 kg / s and can more preferably be in the range of 0.178 to 0.211 kg / s.

[0213] W f,Leerlauf can be in the range of 0.175 to 0.263 kg / s and can preferably be in the range of 0.196 to 0.241 kg / s and can more preferably be in the range of 0.218 to 0.219 kg / s.

[0214] According to a twenty-seventh aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: A fuel flow modified with respect to the climb-nvPM emission index ratio can be defined as follows: EISclimb,SAFEISclimb,FF×Wf,climb where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under given operating conditions and if one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Steigflugthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 85% of the available thrust under the same operating conditions as those in which EI Steigflug,SAF and egg Steigflug,FF to be calculated; the fuel flow rate of the gas turbine engine, modified with respect to the climb-nvPM emission index ratio, is less than 3 kg / s; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0215] The fuel flow and / or W modified with respect to the climb-nvPM emission index ratio f,Steigflug can be defined as above in connection with the twenty-sixth aspect.

[0216] According to a twenty-eighth aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: A fuel flow modified with respect to the approach nvPM emission index ratio can be defined as follows: EI approach, SAFEIA approach, FF×Wf, approach where: EGG Anflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of the available thrust under the given operating conditions or under other operating conditions, and if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Anflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Anflugthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 30% of the available thrust under the same operating conditions as those in which EI Anflug,SAF and egg Anflug,FF to be calculated; and where the fuel flow rate of the gas turbine engine, modified with respect to the approach-nvPM emission index ratio, is less than 0.9 kg / s; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0217] The fuel flow and / or W modified with respect to the approach-nvPM emission index ratio f,Anflug can be defined as above in connection with the twenty-sixth aspect.

[0218] According to a twenty-ninth aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: A fuel flow modified with respect to the idle-nvPM emission index ratio can be defined as follows: Idle run, safe idle run, FF×Wf, idle where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, and if a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel; and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Leeriaufthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 7% of the available thrust under the same operating conditions as those in which EI Leerlauf,SAF and egg Leerlauf,FF to be calculated; the fuel flow rate of the gas turbine engine, modified with respect to the idle-nvPM emission index ratio, is less than 0.3 kg / s; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0219] The fuel flow modified with respect to the idle-nvPM emission index ratio and / or W f,Leerlauf can be defined as above in connection with the twenty-sixth aspect.

[0220] According to a thirtieth aspect, a method for operating the gas turbine engine is provided according to one or more of the twenty-sixth, twenty-seventh, twenty-eighth or twenty-ninth aspects, the method comprising the provision of fuel comprising a sustainable aviation fuel to the majority of fuel spray nozzles.

[0221] According to a thirty-first aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; where: A fuel stream modified with respect to the MTO-nvPM emission index ratio can be defined as follows: EImaxTO,SAFEImaxTO,FF×Wf,maxTO where: EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that includes sustainable aviation fuel (SAF); EGG maxTO,FF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies a fossil-based hydrocarbon fuel; and W f,maxTOthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 100% of the available thrust under the given operating conditions; the fuel flow in kg / s modified with respect to the MTO-nvPM emission index ratio is less than 4; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0222] The fuel flow modified with respect to the MTO-nvPM emission index ratio and / or W f,maxTO can be defined as above in connection with the twenty-sixth aspect.

[0223] A fuel flow modified with respect to the climb-nvPM emission index ratio can be defined as follows: EISclimb,SAFEISclimb,FF×Wf,climb where: EGG Steigflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Steigflugthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 85% of the available thrust under the same operating conditions as those in which EI Steigflug,SAF and egg Steigflug,FF to be calculated; and where the fuel flow of the gas turbine engine (10) modified with respect to the climb-nvPM emission index ratio may be less than 3 in kg / s.

[0224] The fuel flow and / or W modified with respect to the climb-nvPM emission index ratio f,Steigflug can be defined as above in connection with the twenty-sixth aspect.

[0225] A fuel flow modified with respect to the approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEIA approach, FF×Wf, approach where: EGG Anflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Anflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Anflugthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 30% of the available thrust under the same operating conditions as those in which EI Anflug,SAF and egg Anflug,FF to be calculated; and where the fuel flow of the gas turbine engine (10) modified with respect to the approach nvPM emission index ratio may be less than 0.9 in kg / s.

[0226] The fuel flow and / or W modified with respect to the approach-nvPM emission index ratio f,Anflug can be defined as above in connection with the twenty-sixth aspect.

[0227] A fuel flow modified with respect to the idle-nvPM emission index ratio can be defined as follows: Idle run, safe idle run, FF×Wf, idle where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Leerlaufthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 7% of the available thrust under the same operating conditions as those in which EI Leerlauf,SAF and egg Leerlauf,FF to be calculated; and where The fuel flow rate of the gas turbine engine, modified with respect to the idle-nvPM emission index ratio, can be less than 0.3 kg / s.

[0228] The fuel flow modified with respect to the idle-nvPM emission index ratio and / or W f,Leerlauf can be defined as above in connection with the twenty-sixth aspect.

[0229] According to a thirty-second aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: A fuel flow modified with respect to the climb-nvPM emission index ratio can be defined as follows: Idle run, safe idle run, FF×Wf, idle where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under given operating conditions and if one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Steigflugthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 85% of the available thrust under the same operating conditions as those in which EI Steigflug,SAF and egg Steigflug,FF to be calculated; the fuel flow rate of the gas turbine engine, modified with respect to the climb-nvPM emission index ratio, is less than 3 kg / s; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0230] The fuel flow and / or W modified with respect to the climb-nvPM emission index ratio f,Steigflug can be defined as above in connection with the twenty-sixth aspect.

[0231] According to a thirty-third aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: A fuel flow modified with respect to the approach nvPM emission index ratio can be defined as follows: EI approach, SAFEIA approach, FF×Wf, approach where: EGG Anflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Anflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Anflugthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 30% of the available thrust under the same operating conditions as those in which EI Anflug,SAF and egg Anflug,FF to be calculated; the fuel flow rate of the gas turbine engine, modified with respect to the approach-nvPM emission index ratio, is less than 0.9 kg / s; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0232] The fuel flow and / or W modified with respect to the approach-nvPM emission index ratio f,Anflug can be defined as above in connection with the twenty-sixth aspect.

[0233] According to a thirty-fourth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; and wherein: A fuel flow modified with respect to the idle-nvPM emission index ratio can be defined as follows: Idle run, safe idle run, FF×Wf, idle where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, and if a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel; and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Leerlaufthe mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 7% of the available thrust under the same operating conditions as those in which EI Leerlauf,SAF and egg Leerlauf,FF to be calculated; the fuel flow rate of the gas turbine engine, modified with respect to the idle-nvPM emission index ratio, is less than 0.3 kg / s; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0234] The fuel flow modified with respect to the idle-nvPM emission index ratio and / or W f,Leerlauf can be defined as above in connection with the twenty-sixth aspect.

[0235] According to a thirty-fifth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; where: An nvPM emission index ratio for lean-burn cruise flight can be defined as follows: EITravelFlight(lean), SAFEITravelFlight(lean), FF where: EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that is a sustainable aviation fuel; EGG Steigflug,SAFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,FF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies a fossil-based hydrocarbon fuel; and EGG Steigflug,FFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies a fossil-based hydrocarbon fuel; the nvPM emission index ratio for cruise flight with lean combustion of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0236] The nvPM emission index ratio for lean-burn cruise flight can be greater than zero.

[0237] The nvPM emission index ratio for lean-burn cruise flight can be less than or equal to 0.9, and preferably less than or equal to 0.8, and more preferably less than or equal to 0.7.

[0238] The nvPM emission index ratio for cruise flight with lean combustion can be less than or equal to 0.677, preferably less than or equal to 0.621 and more preferably less than or equal to 0.564.

[0239] The nvPM emission index ratio for lean-burn cruise flight can be greater than or equal to 0.446, preferably greater than or equal to 0.501 and more preferably greater than or equal to 0.557.

[0240] The nvPM emission index ratio for cruise flight with lean combustion can be in the range of 0.446 to 0.677, preferably in the range of 0.501 to 0.621 and more preferably in the range of 0.557 to 0.564.

[0241] The nvPM emission index ratio for lean-burn cruise flight can be less than or equal to 0.673, preferably less than or equal to 0.617 and more preferably less than or equal to 0.561.

[0242] The nvPM emission index ratio for cruise flight with lean combustion can be greater than or equal to 0.448, preferably greater than or equal to 0.504 and more preferably greater than or equal to 0.56.

[0243] The nvPM emission index ratio for cruise flight with lean combustion can be in the range of 0.448 to 0.673, preferably in the range of 0.504 to 0.617 and more preferably in the range of 0.560 to 0.561.

[0244] The nvPM emission index ratio for lean-burn cruise flight can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0245] The nvPM emission index ratio for lean-burn cruise flight can be 0.446, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.6, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.677 or in any range between any two of these values.

[0246] An nvPM emission index ratio of idle to MTO can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,SAFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and El maxTO,FFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein The nvPM emission index ratio of idle to MTO of the gas turbine engine can be less than 1.

[0247] The nvPM emission index ratio of idle to MTO can be greater than zero.

[0248] The nvPM emission index ratio idle to MTO can be less than or equal to 0.8 and preferably less than or equal to 0.6, more preferably less than or equal to 0.4 and even more preferably less than or equal to 0.2.

[0249] The nvPM emission index ratio idle to MTO can be less than or equal to 0.178, preferably less than or equal to 0.164 and more preferably less than or equal to 0.149.

[0250] The nvPM emission index ratio idle to MTO can be greater than or equal to 0.118 and can preferably be greater than or equal to 0.133 and can more preferably be greater than or equal to 0.148.

[0251] The nvPM emission index ratio idle to MTO can be in the range of 0.118 to 0.178 and can preferably be in the range of 0.133 to 0.164 and can more preferably be in the range of 0.148 to 0.149.

[0252] The nvPM emission index ratio idle to MTO can be less than 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95 or 1, or lie within any range defined by any two of these values.

[0253] The nvPM emission index ratio idle to MTO of the gas turbine engine can be 0.118, 0.12, 0.125, 0.13, 0.135, 0.14, 0.145, 0.15, 0.155, 0.16, 0.165, 0.17, 0.175, 0.178 or lie in any range defined by any two of these values.

[0254] An nvPM emission index ratio for lean-burn cruise flight to MTO can be defined as follows: EIReiseflug(mager),SAFEImaxTO,SAFEIReiseflug(mager),FFEImaxTO,FF where: EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 100% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI maxTO,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI maxTO,SAFis calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI maxTO,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein The nvPM emission index ratio of lean-burn cruise flight to MTO of the gas turbine engine can be less than 1.

[0255] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than zero.

[0256] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.99 and preferably less than or equal to 0.98.

[0257] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.97, preferably less than or equal to 0.961 and more preferably less than or equal to 0.873.

[0258] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.69, preferably greater than or equal to 0.776 and more preferably greater than or equal to 0.863.

[0259] The nvPM emission index ratio for lean-burn cruise / MTO can be in the range of 0.690 to 0.970, preferably in the range of 0.776 to 0.961 and more preferably in the range of 0.863 to 0.873.

[0260] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.97, preferably less than or equal to 0.955 and more preferably less than or equal to 0.868.

[0261] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.693, preferably greater than or equal to 0.78 and more preferably greater than or equal to 0.867.

[0262] The nvPM emission index ratio for lean-burn cruise / MTO can be in the range of 0.693 to 0.970, preferably in the range of 0.780 to 0.955 and more preferably in the range of 0.867 to 0.868.

[0263] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0264] The nvPM emission index ratio of lean-burn cruise to MTO of the gas turbine engine 10 can be 0.69, 0.7, 0.725, 0.75, 0.775, 0.8, 0.825, 0.85, 0.875, 0.9, 0.925, 0.95, 0.97, 0.99 or lie in any range defined by any two of these values.

[0265] An nvPM emission index ratio of idle to cruise flight with lean combustion can be defined as follows: EILeerlauf, SAFEIReiseflug(magent), SAFEILeerlauf, FFEIReiseflug(magent), FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Leerlauf,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 El maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Steigflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein and where the nvPM emission index ratio of idle to cruise flight with lean combustion of the gas turbine engine can be less than 1.

[0266] The nvPM emission index ratio of idle to cruise flight with lean combustion can be greater than zero.

[0267] The nvPM emission index ratio of idle to cruise flight with lean combustion can be less than or equal to 0.8 and preferably less than or equal to 0.6, more preferably less than or equal to 0.4 and even more preferably less than or equal to 0.3.

[0268] The nvPM emission index ratio of idle to cruise flight with lean combustion can be less than or equal to 0.207, preferably less than or equal to 0.189 and more preferably less than or equal to 0.172.

[0269] The nvPM emission index ratio of idle to cruise flight with lean combustion can be greater than or equal to 0.135, preferably greater than or equal to 0.152 and more preferably greater than or equal to 0.169.

[0270] The nvPM emission index ratio of idle to cruise flight with lean combustion can be in the range of 0.135 to 0.207, preferably in the range of 0.152 to 0.189 and more preferably in the range of 0.169 to 0.172.

[0271] The nvPM emission index ratio of idle to cruise flight with lean combustion can be less than or equal to 0.206, preferably less than or equal to 0.189 and more preferably less than or equal to 0.171.

[0272] The nvPM emission index ratio of idle to cruise flight with lean combustion can be greater than or equal to 0.136, preferably greater than or equal to 0.153 and more preferably greater than or equal to 0.17.

[0273] The nvPM emission index ratio of idle to cruise flight with lean combustion can be in the range of 0.136 to 0.206, preferably in the range of 0.153 to 0.189 and more preferably in the range of 0.170 to 0.171.

[0274] The nvPM emission index ratio idle to cruise flight with lean combustion can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05 or lie within any range defined by any two of these values.

[0275] The nvPM emission index ratio idle to cruise flight with lean combustion can be 0.135, 0.14, 0.145, 0.15, 0.155, 0.16, 0.165, 0.17, 0.175, 0.18, 0.185, 0.19, 0.195, 0.2, 0.205 or 0.207 or lie in any range defined by any two of these values.

[0276] An nvPM emission index ratio for cruise flight with rich combustion can be defined as follows: EITravelFlight(bold), SAFEITravelFlight(bold), FF where: EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 EGG Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 EGG Steigflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAFis calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein The nvPM emission index ratio for cruise flight with rich combustion of the gas turbine engine can be less than 1.

[0277] The nvPM emission index ratio for cruise flight with rich combustion can be greater than zero.

[0278] The nvPM emission index ratio for cruise flight with rich combustion can be less than or equal to 0.8, preferably less than or equal to 0.6 and more preferably less than or equal to 0.4.

[0279] The nvPM emission index ratio for cruise flight with rich combustion can be less than or equal to 0.325, preferably less than or equal to 0.298 and more preferably less than or equal to 0.271.

[0280] The nvPM emission index ratio for cruise flight with rich combustion can be greater than or equal to 0.18, preferably greater than or equal to 0.202 and more preferably greater than or equal to 0.225.

[0281] The nvPM emission index ratio for cruise flight with rich combustion can be in the range of 0.180 to 0.325, preferably in the range of 0.202 to 0.298 and more preferably in the range of 0.225 to 0.271.

[0282] The nvPM emission index ratio for cruise flight with rich combustion can be less than or equal to 0.287, preferably less than or equal to 0.263 and more preferably less than or equal to 0.239.

[0283] The nvPM emission index ratio for cruise flight with rich combustion can be greater than or equal to 0.19, preferably greater than or equal to 0.214 and more preferably greater than or equal to 0.238.

[0284] The nvPM emission index ratio for cruise flight with rich combustion can be in the range of 0.190 to 0.287, preferably in the range of 0.214 to 0.263 and more preferably in the range of 0.238 to 0.239.

[0285] More generally, the nvPM emission index ratio for cruise flight with rich combustion of the gas turbine engine can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or lie within any range defined by any two of these values.

[0286] The nvPM emission index ratio for cruise flight with rich combustion of the gas turbine engine can be 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.325 or lie in any range defined by any two of these values.

[0287] An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIcruise(bold),SAFEImaxTO,SAFEIcruise(bold),FFEImaxTO,FF where: EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 and egg Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 and whereby: EGG Steigflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAFis calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; and EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein The nvPM emission index ratio of cruise flight with rich combustion to MTO of the gas turbine engine can be less than 1.

[0288] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than zero.

[0289] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.8, preferably less than or equal to 0.7 and more preferably less than or equal to 0.6.

[0290] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.503, preferably less than or equal to 0.461 and more preferably less than or equal to 0.419.

[0291] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.279, preferably greater than or equal to 0.313 and more preferably greater than or equal to 0.348.

[0292] The nvPM emission index ratio for cruise flight with rich combustion / to MTO can be in the range of 0.279 to 0.503, preferably in the range of 0.313 to 0.461 and more preferably in the range of 0.348 to 0.419.

[0293] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.444, preferably less than or equal to 0.407 and more preferably less than or equal to 0.37.

[0294] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.295, preferably greater than or equal to 0.332 and more preferably greater than or equal to 0.369.

[0295] The nvPM emission index ratio for cruise flight with rich combustion / to MTO can be in the range of 0.295 to 0.444, preferably in the range of 0.332 to 0.407 and more preferably in the range of 0.369 to 0.370.

[0296] More generally, the nvPM emission index ratio of rich-burn cruise / MTO of the gas turbine engine can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or lie within any range defined by any two of these values.

[0297] The nvPM emission index ratio for cruise flight with rich combustion / to MTO can be 0.279, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.503 or in any range between any two of these values.

[0298] An nvPM emission index ratio of idle to cruise flight with rich combustion can be defined as follows: EILeerlauf,SAFEIReiseflug(fett),SAFEILeerlauf,FFEIReiseflug(fett),FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); EGG Leerlauf,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 EGG Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 EGG Steigflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Leedauf,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein and where the nvPM emission index ratio of idle to cruise flight with rich combustion of the gas turbine engine can be less than 1.

[0299] The nvPM emission index ratio of idle to cruise flight with rich combustion can be greater than zero.

[0300] The nvPM emission index ratio of idle to cruise flight with rich combustion can be less than or equal to 0.9 and preferably less than or equal to 0.8 and more preferably less than or equal to 0.7.

[0301] The nvPM emission index ratio of idle to cruise flight with rich combustion can be less than or equal to 0.511, preferably less than or equal to 0.468 and more preferably less than or equal to 0.426.

[0302] The nvPM emission index ratio of idle to cruise flight with rich combustion can be greater than or equal to 0.283, preferably greater than or equal to 0.319 and more preferably greater than or equal to 0.354.

[0303] The nvPM emission index ratio of idle to cruise flight with rich combustion can be in the range of 0.283 to 0.511, preferably in the range of 0.319 to 0.468 and more preferably in the range of 0.354 to 0.426.

[0304] The nvPM emission index ratio of idle to cruise flight with rich combustion can be less than or equal to 0.482, preferably less than or equal to 0.442 and more preferably less than or equal to 0.402.

[0305] The nvPM emission index ratio of idle to cruise flight with rich combustion can be greater than or equal to 0.321, preferably greater than or equal to 0.361 and more preferably greater than or equal to 0.401.

[0306] The nvPM emission index ratio of idle to cruise flight with rich combustion can be in the range of 0.321 to 0.482, preferably in the range of 0.361 to 0.442 and more preferably in the range of 0.401 to 0.402.

[0307] More generally, the nvPM emission index ratio of idle to cruise flight with rich combustion of the gas turbine engine can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or lie within any range defined by any two of these values.

[0308] The nvPM emission index ratio of idle to cruise flight with rich combustion can be 0.283, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.511 or in any range between any two of these values.

[0309] According to a thirty-sixth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio of idle to MTO can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, when a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAFis calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and El maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio (idle to MTO) of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0310] The nvPM emission index ratio idle to MTO can be defined as above in connection with the thirty-fifth aspect.

[0311] According to a thirty-seventh aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; where: An nvPM emission index ratio for lean-burn cruise flight to MTO can be defined as follows: EIReiseflug(mager),SAFEImaxTO,SAFEIReiseflug(mager),FFEImaxTO,FF where: EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that is a sustainable aviation fuel; EGG Steigflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI maxTO,SAFis calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI maxTO,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI maxTO,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio of lean-burn cruise flight to MTO of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0312] The nvPM emission index ratio of lean-burn cruise to MTO can be defined as above in connection with the thirty-fifth aspect.

[0313] According to a thirty-eighth aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio of idle to cruise flight with lean combustion can be defined as follows: EILeerlauf, SAFEIReiseflug(magent), SAFEILeerlauf, FFEIReiseflug(magent), FF where: EGG Leerlauf,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, when a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel; EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,SAFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,FFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leedauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio of idle to cruise flight with lean combustion of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0314] The nvPM emission index ratio of idle to cruise flight with lean combustion can be defined as above in connection with the thirty-fifth aspect.

[0315] According to a thirty-ninth aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio for cruise flight with rich combustion can be defined as follows: EITravelFlight(bold), SAFEITravelFlight(bold), FF where: EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 EGG Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 EGG Steigflug,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio for cruise flight with rich combustion of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0316] The nvPM emission index ratio for cruise flight with rich combustion can be defined as above in relation to the thirty-fifth aspect.

[0317] According to a fortieth aspect, a gas turbine engine is provided for an aircraft, which includes one or more of the following elements: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIcruise(bold),SAFEImaxTO,SAFEIcruise(bold),FFEImaxTO,FF where: EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 and egg Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 and whereby: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under given operating conditions and if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAFis calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; and EGG maxTO,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 100% of available thrust under the same operating conditions as those under which EI climb,SAF is calculated, when one of the fuels supplied by the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio of cruise flight with rich combustion to MTO of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0318] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be defined as above in connection with the thirty-fifth aspect.

[0319] According to a forty-first aspect, a gas turbine engine is provided for an aircraft, which includes one or more of the following elements: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio of idle to cruise flight with rich combustion can be defined as follows: EILeerlauf,SAFEIReiseflug(fett),SAFEILeerlauf,FFEIReiseflug(fett),FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions, and if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 EGG Reiseflug(fett),FFwhich can be defined as follows: E-climb, FF+E-approach, FF2 EGG Steigflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Anflug,SAFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio of idle to cruise flight with rich combustion of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0320] The nvPM emission index ratio of idle to cruise flight with rich combustion can be defined as above in connection with the thirty-fifth aspect.

[0321] According to a forty-second aspect, a method for operating the gas turbine engine of any or any of the thirty-fifth, thirty-sixth, thirty-seventh, thirty-eighth, thirty-ninth, fortieth or forty-first aspects is provided, the method comprising the provision of fuel comprising a sustainable aviation fuel to the plurality of fuel spray nozzles.

[0322] According to a forty-third aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; where: An nvPM emission index ratio for lean-burn cruise flight can be defined as follows: EITravelFlight(lean), SAFEITravelFlight(lean), FF where: EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that is a sustainable aviation fuel; EGG Steigflug,SAFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,FF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under the given operating conditions, where one of the fuels supplied by the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EI Steigflug,FFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies a fossil-based hydrocarbon fuel; the nvPM emission index ratio for lean-burn cruise flight is less than 1; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0323] The nvPM emission index ratio for lean-burn cruise flight can be defined as above in relation to the thirty-fifth aspect.

[0324] An nvPM emission index ratio of idle to MTO can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGGLeerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EILeerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and The nvPM emission index ratio of idle to MTO of the gas turbine engine can be less than 1.

[0325] The nvPM emission index ratio idle to MTO can be defined as above in connection with the thirty-fifth aspect.

[0326] An nvPM emission index ratio for lean-burn cruise flight to MTO can be defined as follows: EIReiseflug(mager),SAFEImaxTO,SAFEIReiseflug(mager),FFEImaxTO,FF where: EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 100% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,SAFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI maxTO,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI maxTO,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Steigflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI maxTO,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein The nvPM emission index ratio of lean-burn cruise flight to MTO of the gas turbine engine can be less than 1.

[0327] The nvPM emission index ratio of lean-burn cruise to MTO can be defined as above in connection with the thirty-fifth aspect.

[0328] An nvPM emission index ratio of idle to cruise flight with lean combustion can be defined as follows: EILeerlauf, SAFEIReiseflug(magent), SAFEILeerlauf, FFEIReiseflug(magent), FF where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,SAFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,FFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein and where the nvPM emission index ratio of idle to cruise flight with lean combustion of the gas turbine engine can be less than 1.

[0329] The nvPM emission index ratio of idle to cruise flight with lean combustion can be defined as above in connection with the thirty-fifth aspect.

[0330] An nvPM emission index ratio for cruise flight with rich combustion can be defined as follows: EITravelFlight(bold), SAFEITravelFlight(bold), FF where: EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 EGG Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Anflug,SAFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Anflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; and wherein The nvPM emission index ratio for cruise flight with rich combustion of the gas turbine engine can be less than 1.

[0331] The nvPM emission index ratio for cruise flight with rich combustion can be defined as above in relation to the thirty-fifth aspect.

[0332] An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIcruise(bold),SAFEImaxTO,SAFEIcruise(bold),FFEImaxTO,FF where: EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 and egg Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 and whereby: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG maxTO,SAFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; and EGG maxTO,FF the system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 100% of available thrust under the same operating conditions as those under which EI climb,SAF is calculated, if one of the fuels supplied by the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and The nvPM emission index ratio of cruise flight with rich combustion to MTO of the gas turbine engine can be less than 1.

[0333] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be defined as above in connection with the thirty-fifth aspect.

[0334] An nvPM emission index ratio of idle to cruise flight with rich combustion can be defined as follows: EILeerlauf,SAFEIReiseflug(fett),SAFEILeerlauf,FFEIReiseflug(fett),FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); EGG Leerlauf,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 EGG Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 EGG Steigflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and and where the nvPM emission index ratio of idle to cruise flight with rich combustion of the gas turbine engine can be less than 1.

[0335] The nvPM emission index ratio of idle to cruise flight with rich combustion can be defined as above in connection with the thirty-fifth aspect.

[0336] According to a forty-fourth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio of idle to MTO can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, when a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAFis calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio (idle to MTO) of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0337] The nvPM emission index ratio idle to MTO can be defined as above in connection with the thirty-fifth aspect.

[0338] According to a forty-fifth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio for lean-burn cruise flight to MTO can be defined as follows: EIReiseflug(mager),SAFEImaxTO,SAFEIReiseflug(mager),FFEImaxTO,FF where: EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that is a sustainable aviation fuel; EGG Steigflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI maxTO,SAFis calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI maxTO,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI maxTO,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio of lean-burn cruise flight to MTO of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0339] The nvPM emission index ratio of lean-burn cruise to MTO can be defined as above in connection with the thirty-fifth aspect.

[0340] According to a forty-sixth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio of idle to cruise flight with lean combustion can be defined as follows: EILeerlauf, SAFEIReiseflug(magent), SAFEILeerlauf, FFEIReiseflug(magent), FF where: EGG Leerlauf,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, when a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel; EGG Reiseflug(mager),SAF which can be defined as follows: EImaxTO,SAF+EISsteigflug,SAF2 EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,SAFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Reiseflug(mager),FF which can be defined as follows: EImaxTO,FF+EISteigflug,FF2 EGG maxTO,FFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio of idle to cruise flight with lean combustion of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0341] The nvPM emission index ratio of idle to cruise flight with lean combustion can be defined as above in connection with the thirty-fifth aspect.

[0342] According to a forty-seventh aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio for cruise flight with rich combustion can be defined as follows: EITravelFlight(bold), SAFEITravelFlight(bold), FF where: EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 EGG Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 EGG Steigflug,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio for cruise flight with rich combustion of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0343] The nvPM emission index ratio for cruise flight with rich combustion can be defined as above in relation to the thirty-fifth aspect.

[0344] According to a forty-eighth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIcruise(bold),SAFEImaxTO,SAFEIcruise(bold),FFEImaxTO,FF where: EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 and egg Reiseflug(fett),FF which can be defined as follows: E-climb, FF+E-approach, FF2 and whereby: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under given operating conditions and if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; EGG Anflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAFis calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; and EGG maxTO,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 100% of available thrust under the same operating conditions as those under which EI climb,SAF is calculated, when one of the fuels supplied by the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio of cruise flight with rich combustion to MTO of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0345] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be defined as above in connection with the thirty-fifth aspect.

[0346] According to a forty-ninth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: A combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustion chamber is operable in a state in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a higher flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein the ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6; wherein: An nvPM emission index ratio of idle to cruise flight with rich combustion can be defined as follows: EILeerlauf,SAFEIReiseflug(fett),SAFEILeerlauf,FFEIReiseflug(fett),FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions, and if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Reiseflug(fett),SAF which can be defined as follows: E-climb, SAF+E-approach, SAF2 EGG Reiseflug(fett),FFwhich can be defined as follows: E-climb, FF+E-approach, FF2 EGG Steigflug,SAF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; EGG Anflug,SAFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when a fuel supplied to the multitude of fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Leerlauf,SAF is calculated when the fuel supplied to one of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; the nvPM emission index ratio of idle to cruise flight with rich combustion of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel (SAF) to the multitude of fuel spray nozzles.

[0347] The nvPM emission index ratio of idle to cruise flight with rich combustion can be defined as above in connection with the thirty-fifth aspect.

[0348] The following statements can apply to each of aspects one through forty-nine:

[0349] The ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles can be in the range of 1:4 to 1:5.

[0350] The ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles can be in the range of 1:4.25 to 1:4.75.

[0351] The first subset of fuel spray nozzles can include between 1 and 10 fuel spray nozzles.

[0352] The first subset of fuel spray nozzles can include between 3 and 5 fuel spray nozzles.

[0353] The second subset of fuel spray nozzles can include between 10 and 25 fuel spray nozzles.

[0354] The second subset of fuel spray nozzles can include between 14 and 22 fuel spray nozzles.

[0355] The second subset of fuel spray nozzles can include between 16 and 20 fuel spray nozzles.

[0356] The combustion chamber can include one or more igniters.

[0357] Each of the first subset of fuel spray nozzles can be positioned closer to one or more of the igniters than the second subset.

[0358] One or more of the detonators can be arranged diametrically opposite one or more other detonators.

[0359] The fuel supplied to the fuel spray nozzles can contain a %SAF in the range of 50% to 100%.

[0360] The fuel supplied to the fuel spray nozzles can have a %SAF in the range of 70% to 100%.

[0361] The fuel supplied to the fuel spray nozzles can have a %SAF in the range of 90% to 100%.

[0362] According to a fiftieth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a variety of fuel spray nozzles configured to inject fuel into the combustion chamber; where: A first nvPM emission index ratio of idle to MTO (maximum take-off) can be defined as follows: EILeerlaufEImaxTO where: ET Leerlauf the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions; and EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; the first nvPM emission index ratio idle to MTO of the gas turbine engine is less than 2; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0363] The first nvPM emission index ratio idle to MTO of the gas turbine engine can be greater than zero.

[0364] The first nvPM emission index ratio idle to MTO can be less than 1.26 and preferably less than 1.16 and more preferably less than 1.05.

[0365] The first nvPM emission index ratio idle to MTO can be less than 1.15 and preferably less than 1.05 and more preferably less than 0.951.

[0366] The first nvPM emission index ratio idle to MTO can be less than 0.96 and preferably less than 0.88 and more preferably less than 0.8.

[0367] The first nvPM emission index ratio idle to MTO can be less than 0.791 and preferably less than 0.725 and more preferably less than 0.659.

[0368] The first nvPM emission index ratio idle to MTO can be less than 0.415 and preferably less than 0.381 and more preferably less than 0.346.

[0369] The first nvPM emission index ratio idle to MTO can be less than 1.5 and preferably less than 1 and more preferably less than 0.5.

[0370] The first nvPM emission index ratio idle to MTO can be less than or equal to 0.187, and preferably less than or equal to 0.171, and more preferably less than or equal to 0.156.

[0371] The first nvPM emission index ratio idle to MTO can be less than or equal to 0.143, and preferably less than or equal to 0.131, and more preferably less than or equal to 0.119.

[0372] The first nvPM emission index ratio idle to MTO can be less than or equal to 0.170, and preferably less than or equal to 0.156, and more preferably less than or equal to 0.142.

[0373] The first nvPM emission index ratio idle to MTO can be less than or equal to 0.0615 and can preferably be less than or equal to 0.0564 and can more preferably be less than or equal to 0.0513.

[0374] The first nvPM emission index ratio idle to MTO can be less than or equal to 0.118, and preferably less than or equal to 0.108, and more preferably less than or equal to 0.0978.

[0375] The first nvPM emission index ratio idle to MTO can be greater than or equal to 0.0409 and can preferably be greater than or equal to 0.0461 and can more preferably be greater than or equal to 0.0512.

[0376] The first nvPM emission index ratio idle to MTO can be greater than or equal to 0.0956 and can preferably be greater than or equal to 0.107 and can more preferably be greater than or equal to 0.119.

[0377] The first nvPM emission index ratio idle to MTO can be greater than or equal to 0.0509 and can preferably be greater than or equal to 0.0573 and can more preferably be greater than or equal to 0.0636.

[0378] The first nvPM emission index ratio idle to MTO can be greater than or equal to 0.124 and can preferably be greater than or equal to 0.139 and can more preferably be greater than or equal to 0.155.

[0379] The first nvPM emission index ratio idle to MTO can be greater than or equal to 0.0524 and can preferably be greater than or equal to 0.059 and can more preferably be greater than or equal to 0.0656.

[0380] The first nvPM emission index ratio idle to MTO can be in the range of 0.0409 to 0.187, and preferably in the range of 0.0461 to 0.171, and more preferably in the range of 0.0512 to 0.156.

[0381] The first nvPM emission index ratio idle to MTO can be in the range of 0.0956 to 0.187 and can preferably be in the range of 0.107 to 0.171 and can more preferably be in the range of 0.119 to 0.156.

[0382] The first nvPM emission index ratio idle to MTO can be in the range of 0.0509 to 0.143 and can preferably be in the range of 0.0573 to 0.131 and can more preferably be in the range of 0.0636 to 0.119.

[0383] The first nvPM emission index ratio idle to MTO can be in the range of 0.0956 to 0.17 and can preferably be in the range of 0.107 to 0.156 and can more preferably be in the range of 0.119 to 0.142.

[0384] The first nvPM emission index ratio idle to MTO can be in the range of 0.124 to 0.187 and can preferably be in the range of 0.139 to 0.171 and can more preferably be in the range of 0.155 to 0.156.

[0385] The first nvPM emission index ratio idle to MTO can be in the range of 0.0409 to 0.0615 and can preferably be in the range of 0.0461 to 0.0564 and can more preferably be in the range of 0.0512 to 0.0513.

[0386] The first nvPM emission index ratio idle to MTO can be in the range of 0.0524 to 0.118 and can preferably be in the range of 0.059 to 0.108 and can more preferably be in the range of 0.0656 to 0.0978.

[0387] The first nvPM emission index ratio idle to MTO can be less than 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2 or lie within any range defined by any two of these values.

[0388] A second nvPM emission index ratio, idle to MTO, can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, and if a fuel supplied to the combustion chamber includes a sustainable aviation fuel; EGG maxTO,SAFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if a fuel supplied to the combustion chamber includes a sustainable aviation fuel, is; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; EGG maxTO,FFThe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; and where the second nvPM emission index ratio idle to MTO of the gas turbine engine can be less than 1.

[0389] The second nvPM emission index ratio, idle to MTO, can be greater than zero.

[0390] The second nvPM emission index ratio, idle to MTO, can be less than or equal to 0.8, and preferably less than or equal to 0.6, and more preferably less than or equal to 0.4.

[0391] The second nvPM emission index ratio, idle to MTO, can be less than or equal to 0.178, and preferably less than or equal to 0.164, and more preferably less than or equal to 0.149.

[0392] The second nvPM emission index ratio, idle to MTO, can be greater than or equal to 0.03, and preferably greater than or equal to 0.06, and more preferably greater than or equal to 0.09.

[0393] The second nvPM emission index ratio, idle to MTO, can be greater than or equal to 0.118, and preferably greater than or equal to 0.133, and more preferably greater than or equal to 0.148.

[0394] The second nvPM emission index ratio, idle to MTO, can be in the range of 0.118 to 0.178, and preferably in the range of 0.133 to 0.164, and more preferably in the range of 0.148 to 0.149.

[0395] The second nvPM emission index ratio, idle to MTO, can be less than 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95 or 1, or lie within any range defined by any two of these values.

[0396] According to a fifty-first aspect, a gas turbine engine is provided for an aircraft, which includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A second nvPM emission index ratio, idle to MTO, can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions and if a fuel supplied to the combustion chamber includes a sustainable aviation fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if a fuel supplied to the combustion chamber includes a sustainable aviation fuel, is; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAFis calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; the second nvPM emission index ratio idle to MTO of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0397] The fifty-first nvPM emission index ratio idle to MTO defined in the second aspect can be defined in the context of the fiftieth aspect as above.

[0398] According to a fifty-second aspect, a method for operating the gas turbine engine of the fiftieth aspect or the fifty-first aspect is provided, the method comprising the provision of fuel comprising a sustainable aviation fuel for the plurality of fuel spray nozzles.

[0399] According to a fifty-third aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A first nvPM emission index ratio of idle to MTO (maximum take-off) can be defined as follows: EILeerlaufEImaxTO where: ET Leerlauf the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions; and EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; the first nvPM emission index ratio idle to MTO of the gas turbine engine is less than 2; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0400] The first nvPM emission index ratio idle to MTO can be defined as above in connection with the fiftieth aspect.

[0401] A second nvPM emission index ratio, idle to MTO, can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under the given operating conditions or under other operating conditions, and if a fuel supplied to the combustion chamber includes a sustainable aviation fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAFis calculated, and, if a fuel supplied to the combustion chamber includes a sustainable aviation fuel, is; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; and where the second nvPM emission index ratio, idle to MTO of the gas turbine engine, can be less than 1.

[0402] The second nvPM emission index ratio, idle to MTO, can be defined as above in connection with the fiftieth aspect.

[0403] According to a fifty-fourth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A second nvPM emission index ratio, idle to MTO, can be defined as follows: EILidle,SAFEImaxTO,SAFEILidle,FFEImaxTO,FF where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions and if a fuel supplied to the combustion chamber includes a sustainable aviation fuel; EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if a fuel supplied to the combustion chamber includes a sustainable aviation fuel, is; EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAFis calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; EGG maxTO,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and, if one of the fuels supplied to the combustion chamber is a fossil-based hydrocarbon fuel, is; the second nvPM emission index ratio idle to MTO of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0404] The second nvPM emission index ratio, idle to MTO, can be defined as above in connection with the fiftieth aspect.

[0405] According to a fifty-fifth aspect, a gas turbine engine is provided for an aircraft that includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A fuel flow-nvPM emission index ratio can be defined as follows: EILidle×Wf,IdleEImaxTO×Wf,maxTO where: ET Leerlauf The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 7% of the available thrust under given operating conditions; EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; W f,Leerlaufthe fuel flow rate to the fuel spray nozzles in kg / s is approximately 7% of the available thrust under the given operating conditions; and W f,maxTO the fuel flow rate to the fuel spray nozzles in kg / s at approximately 100% of the available thrust under the given operating conditions; the fuel flow-nvPM emission index ratio of the gas turbine engine is less than 0.2; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0406] The fuel flow nvPM emission index ratio can be less than 0.13 and preferably less than 0.119 and more preferably less than 0.108.

[0407] The fuel flow nvPM emission index ratio can be less than 0.091 and preferably less than 0.0834 and more preferably less than 0.0758.

[0408] The fuel flow-nvPM emission index ratio can be less than 0.123 and preferably less than 0.113 and more preferably less than 0.103.

[0409] The fuel flow nvPM emission index ratio can be less than 0.0819 and preferably less than 0.075 and more preferably less than 0.0682.

[0410] The fuel flow nvPM emission index ratio can be less than 0.0357 and preferably less than 0.0327 and more preferably less than 0.0298.

[0411] The fuel flow-nvPM emission index ratio can be less than 0.17 and preferably less than 0.15 and more preferably less than 0.12.

[0412] The fuel flow nvPM emission index ratio can be less than or equal to 0.0193, can preferably be less than or equal to 0.0177, and can more preferably be less than or equal to 0.0161.

[0413] The fuel flow nvPM emission index ratio can be less than or equal to 0.0135, can preferably be less than or equal to 0.0124, and can more preferably be less than or equal to 0.0113.

[0414] The fuel flow nvPM emission index ratio can be less than or equal to 0.0182, can preferably be less than or equal to 0.0167, and can more preferably be less than or equal to 0.0152.

[0415] The fuel flow nvPM emission index ratio can be less than or equal to 0.00529, can preferably be less than or equal to 0.00485, and can more preferably be less than or equal to 0.00441.

[0416] The fuel flow nvPM emission index ratio can be less than or equal to 0.0122, can preferably be less than or equal to 0.0112, and can more preferably be less than or equal to 0.0102.

[0417] The fuel flow nvPM emission index ratio can be greater than or equal to 0.00352, can preferably be greater than or equal to 0.00396, and can more preferably be greater than or equal to 0.0044.

[0418] The fuel flow nvPM emission index ratio can be greater than or equal to 0.0107, can preferably be greater than or equal to 0.012, and can more preferably be greater than or equal to 0.0133.

[0419] The fuel flow nvPM emission index ratio can be greater than or equal to 0.00561, can preferably be greater than or equal to 0.00631, and can more preferably be greater than or equal to 0.00701.

[0420] The fuel flow nvPM emission index ratio can be greater than or equal to 0.0128, can preferably be greater than or equal to 0.0144, and can more preferably be greater than or equal to 0.016.

[0421] The fuel flow nvPM emission index ratio can be greater than or equal to 0.00564, can preferably be greater than or equal to 0.00635, and can more preferably be greater than or equal to 0.00705.

[0422] The fuel flow nvPM emission index ratio can be in the range of 0.00352 to 0.0193, and preferably in the range of 0.00396 to 0.0177, and even more preferably in the range of 0.00440 to 0.0161.

[0423] The fuel flow nvPM emission index ratio can be in the range of 0.0107 to 0.0193, and preferably in the range of 0.0120 to 0.0177, and even more preferably in the range of 0.0133 to 0.0161.

[0424] The fuel flow nvPM emission index ratio can be in the range of 0.00561 to 0.0135 and can preferably be in the range of 0.00631 to 0.0124 and can more preferably be in the range of 0.00701 to 0.0113.

[0425] The fuel flow nvPM emission index ratio can be in the range of 0.0107 to 0.0182, and preferably in the range of 0.0120 to 0.0167, and even more preferably in the range of 0.0133 to 0.0152.

[0426] The fuel flow nvPM emission index ratio can be in the range of 0.0128 to 0.0193, preferably in the range of 0.0144 to 0.0177, and even more preferably in the range of 0.0160 to 0.0161.

[0427] The fuel flow nvPM emission index ratio can be in the range of 0.00352 to 0.00529, and preferably in the range of 0.00396 to 0.00485, and even more preferably in the range of 0.00440 to 0.00441.

[0428] The fuel flow nvPM emission index ratio can be in the range of 0.00564 to 0.0122, and preferably in the range of 0.00635 to 0.0112, and even more preferably in the range of 0.00705 to 0.0102.

[0429] The fuel flow nvPM emission index ratio can be less than 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19 or 0.2, or in any range between any two of these values.

[0430] W f,Leerlauf in kg / s can be in the range of 0.185 to 0.362 and preferably in the range of 0.209 to 0.331 and particularly preferably in the range of 0.232 to 0.301.

[0431] W f,Leerlauf in kg / s can be in the range of 0.215 to 0.362 and preferably in the range of 0.242 to 0.331 and particularly preferably in the range of 0.269 to 0.301.

[0432] W f,Leerlauf in kg / s can be in the range of 0.215 to 0.349 and preferably in the range of 0.242 to 0.320 and particularly preferably in the range of 0.269 to 0.291.

[0433] W f,Leerlaufin kg / s can be in the range of 0.185 to 0.324 and preferably in the range of 0.209 to 0.297 and particularly preferably in the range of 0.232 to 0.270.

[0434] W f,Leerlauf in kg / s can be in the range of 0.215 to 0.336 and preferably in the range of 0.242 to 0.308 and particularly preferably in the range of 0.269 to 0.280.

[0435] W f,Leerlauf in kg / s can be in the range of 0.232 to 0.349 and preferably in the range of 0.261 to 0.320 and particularly preferably in the range of 0.290 to 0.291.

[0436] W f,Leerlauf in kg / s can be in the range of 0.24 to 0.362 and preferably in the range of 0.27 to 0.331 and particularly preferably in the range of 0.300 to 0.301.

[0437] W f,Leerlauf in kg / s can be in the range of 0.196 to 0.311 and preferably in the range of 0.220 to 0.285 and particularly preferably in the range of 0.245 to 0.259.

[0438] W f,maxTOThe value in kg / s can be in the range of 1.68 to 4.20 and preferably in the range of 1.89 to 3.85 and particularly preferably in the range of 2.10 to 3.50.

[0439] W f,maxTO The value in kg / s can be in the range of 1.92 to 4.20 and preferably in the range of 2.16 to 3.85 and particularly preferably in the range of 2.41 to 3.50.

[0440] W f,maxTO The value in kg / s can be in the range of 1.92 to 3.39 and preferably in the range of 2.16 to 3.11 and particularly preferably in the range of 2.41 to 2.82.

[0441] W f,maxTO in kg / s can be in the range of 1.68 to 3.45 and preferably in the range of 1.89 to 3.16 and particularly preferably in the range of 2.10 to 2.88.

[0442] W f,maxTO The value in kg / s can be in the range of 1.92 to 3.13 and preferably in the range of 2.16 to 2.87 and particularly preferably in the range of 2.41 to 2.61.

[0443] W f,maxTOin kg / s can be in the range of 2.25 to 3.39 and preferably in the range of 2.53 to 3.11 and particularly preferably in the range of 2.81 to 2.82.

[0444] W f,maxTO in kg / s can be in the range of 2.79 to 4.20 and preferably in the range of 3.14 to 3.85 and particularly preferably in the range of 3.49 to 3.50.

[0445] W f,maxTO in kg / s can be in the range of 1.83 to 3.01 and preferably in the range of 2.05 to 2.76 and particularly preferably in the range of 2.28 to 2.51.

[0446] According to a fifty-sixth aspect, a method for operating the gas turbine engine of the fifty-fifth aspect is provided, the method comprising the provision of fuel comprising a sustainable aviation fuel to the plurality of fuel spray nozzles.

[0447] According to a fifty-seventh aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A fuel flow-nvPM emission index ratio can be defined as follows: EILidle×Wf,IdleEImaxTO×Wf,maxTO where: ET Leerlauf the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions; and EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; W f,Leerlaufthe fuel flow rate to the fuel spray nozzles in kg / s is approximately 7% of the available thrust under the given operating conditions; and W f,maxTO the fuel flow rate to the fuel spray nozzles in kg / s at approximately 100% of the available thrust under the given operating conditions; the fuel flow-nvPM emission index ratio of the gas turbine engine is less than 0.2; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0448] Each of the fuel flow nvPM emission index ratios, W f,Leerlauf and W f,maxTO can be defined as above in connection with the fifty-fifth aspect.

[0449] According to a fifty-eighth aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A thrust-nvPM emission index ratio can be defined as follows: EImaxTOFmaxTOEIIdleIdleIdle where: ET Leerlauf The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 7% of the available thrust under given operating conditions; EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; F maxTO the thrust of the gas turbine engine is approximately 100% of the available thrust in kN under the given operating conditions; and F LeerlaufThe thrust of the gas turbine engine is approximately 7% of the available thrust in kN under the given operating conditions; the thrust-nvPM emission index ratio is greater than 0.05; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0450] The thrust-nvPM emission index ratio can be greater than 0.0535 and preferably greater than 0.0602 and more preferably greater than 0.0669.

[0451] The thrust-nvPM emission index ratio can be greater than 0.07 and preferably greater than 0.0788 and more preferably greater than 0.0875.

[0452] The thrust-nvPM emission index ratio can be greater than 0.0588 and preferably greater than 0.0662 and more preferably greater than 0.0736.

[0453] The thrust-nvPM emission index ratio can be greater than 0.162 and preferably greater than 0.182 and more preferably greater than 0.202.

[0454] The thrust-nvPM emission index ratio can be greater than 0.0849 and preferably greater than 0.0956 and more preferably greater than 0.106.

[0455] The thrust-nvPM emission index ratio can be greater than or equal to 0.1, can preferably be greater than or equal to 0.2, and can more preferably be greater than or equal to 0.3.

[0456] The thrust-nvPM emission index ratio can be greater than or equal to 0.36, can preferably be greater than or equal to 0.405, and can more preferably be greater than or equal to 0.451.

[0457] The thrust-nvPM emission index ratio can be greater than or equal to 0.472, can preferably be greater than or equal to 0.531, and can more preferably be greater than or equal to 0.59.

[0458] The thrust-nvPM emission index ratio can be greater than or equal to 0.397, can preferably be greater than or equal to 0.446, and can more preferably be greater than or equal to 0.496.

[0459] The thrust-nvPM emission index ratio can be greater than or equal to 1.09, can preferably be greater than or equal to 1.22, and can more preferably be greater than or equal to 1.36.

[0460] The thrust-nvPM emission index ratio can be greater than or equal to 0.572, can preferably be greater than or equal to 0.644, and can more preferably be greater than or equal to 0.716.

[0461] The thrust-nvPM emission index ratio can be less than or equal to 1.64, can preferably be less than or equal to 1.51, and can more preferably be less than or equal to 1.37.

[0462] The thrust-nvPM emission index ratio can be less than or equal to 0.703, can preferably be less than or equal to 0.645, and can more preferably be less than or equal to 0.586.

[0463] The thrust-nvPM emission index ratio can be less than or equal to 1.32, can preferably be less than or equal to 1.21, and can more preferably be less than or equal to 1.1.

[0464] The thrust-nvPM emission index ratio can be less than or equal to 0.542, can preferably be less than or equal to 0.497, and can more preferably be less than or equal to 0.452.

[0465] The thrust-nvPM emission index ratio can be less than or equal to 1.64, can preferably be less than or equal to 1.51, and can more preferably be less than or equal to 1.37.

[0466] The thrust-nvPM emission index ratio can be less than or equal to 1.29, can preferably be less than or equal to 1.18, and can more preferably be less than or equal to 1.07.

[0467] The thrust-nvPM emission index ratio can be less than 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, 0.055, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, 0.09, 0.095, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2 or a range between any two of these values.

[0468] The thrust-nvPM emission index ratio can be in the range of 0.36 to 1.64, and preferably in the range of 0.405 to 1.51, and more preferably in the range of 0.451 to 1.37.

[0469] The thrust-nvPM emission index ratio can be in the range of 0.36 to 0.703, and preferably in the range of 0.405 to 0.645, and more preferably in the range of 0.451 to 0.586.

[0470] The thrust-nvPM emission index ratio can be in the range of 0.472 to 1.32, and preferably in the range of 0.531 to 1.21, and more preferably in the range of 0.59 to 1.1.

[0471] The thrust-nvPM emission index ratio can be in the range of 0.397 to 0.703, and preferably in the range of 0.446 to 0.645, and more preferably in the range of 0.496 to 0.586.

[0472] The thrust-nvPM emission index ratio can be in the range of 0.360 to 0.542, and preferably in the range of 0.405 to 0.497, and more preferably in the range of 0.451 to 0.452.

[0473] The thrust-nvPM emission index ratio can be in the range of 1.09 to 1.64, and preferably in the range of 1.22 to 1.51, and more preferably in the range of 1.36 to 1.37.

[0474] The thrust-nvPM emission index ratio can be in the range of 0.572 to 1.29, and preferably in the range of 0.644 to 1.18, and more preferably in the range of 0.716 to 1.07.

[0475] F maxTO The value in kN can be in the range of 229 to 525, preferably in the range of 258 to 481, and particularly preferably in the range of 287 to 437.

[0476] F maxTO The value in kN can be in the range of 267 to 525, preferably in the range of 300 to 481, and particularly preferably in the range of 334 to 437.

[0477] F maxTO The value in kN can be in the range of 267 to 455, preferably in the range of 300 to 417, and particularly preferably in the range of 334 to 380.

[0478] F maxTO The value in kN can be in the range of 229 to 437, preferably in the range of 258 to 401, and particularly preferably in the range of 287 to 364.

[0479] F maxTOThe value in kN can be in the range of 267 to 427, preferably in the range of 300 to 391, and particularly preferably in the range of 334 to 356.

[0480] F maxTO The value in kN can be in the range of 303 to 455, preferably in the range of 341 to 417, and particularly preferably in the range of 379 to 380.

[0481] F maxTO The value in kN can be in the range of 349 to 525, preferably in the range of 393 to 481, and particularly preferably in the range of 436 to 437.

[0482] F maxTO The value in kN can be in the range of 246 to 394, preferably in the range of 277 to 361, and particularly preferably in the range of 308 to 328.

[0483] F Leerlauf The value in kN can be in the range of 16.0 to 36.7, preferably in the range of 18.0 to 33.7, and particularly preferably in the range of 20.0 to 30.6.

[0484] F LeerlaufThe value in kN can be in the range of 18.7 to 36.7, preferably in the range of 21.0 to 33.7, and particularly preferably in the range of 23.3 to 30.6.

[0485] F Leerlauf The value in kN can be in the range of 18.7 to 31.9, preferably in the range of 21.0 to 29.2, and particularly preferably in the range of 23.3 to 26.6.

[0486] F Leerlauf The value in kN can be in the range of 16.0 to 30.6, preferably in the range of 18.0 to 28.1, and particularly preferably in the range of 20.0 to 25.5.

[0487] F Leerlauf The value in kN can be in the range of 18.7 to 29.9, preferably in the range of 21.0 to 27.4, and particularly preferably in the range of 23.3 to 24.9.

[0488] F Leerlauf The value in kN can be in the range of 21.2 to 31.9, preferably in the range of 23.8 to 29.2, and particularly preferably in the range of 26.5 to 26.6.

[0489] F LeerlaufThe value in kN can be in the range of 24.4 to 36.7, preferably in the range of 27.5 to 33.7, and particularly preferably in the range of 30.5 to 30.6.

[0490] F Leerlauf The value in kN can be in the range of 17.2 to 27.6, preferably in the range of 19.4 to 25.3, and particularly preferably in the range of 21.6 to 23.0.

[0491] According to a fifty-ninth aspect, a method for operating the gas turbine engine of the fifty-eighth aspect is provided, the method comprising the provision of fuel comprising a sustainable aviation fuel to the plurality of fuel spray nozzles.

[0492] According to a sixteenth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A thrust-nvPM emission index ratio can be defined as follows: EImaxTOFmaxTOEIIdleIdleIdle where: ET Leerlauf the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions; and EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, is mg / kg when operating at approximately 100% of the available thrust under the given operating conditions; F maxTO The thrust of the gas turbine engine at approximately 100% of the available thrust in kN under the given operating conditions is, F LeerlaufThe thrust of the gas turbine engine is approximately 7% of the available thrust in kN under the given operating conditions; and the thrust-nvPM emission index ratio is greater than 0.05; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0493] Each of the thrust-nvPM emission index ratios, F maxTO and F Leerlauf can be defined as in connection with the fifty-eighth aspect.

[0494] According to a sixty-first aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An nvPM emission index ratio for lean-burn cruise flight to MTO can be defined as follows: EIReiseflug(meier)EImaxTOBPR where: EGG Reiseflug(mager) which can be defined as follows: EImaxTO+EISteigflug2 EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 100% of the available thrust under the given operating conditions; EGG Steigflug the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions; and BPR is the bypass ratio of the gas turbine engine; the nvPM emission index ratio of lean-burn cruise to MTO is less than 0.2; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0495] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.194 and preferably less than 0.178 and more preferably less than 0.162.

[0496] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.19 and preferably less than 0.174 and more preferably less than 0.158.

[0497] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.181 and preferably less than 0.166 and more preferably less than 0.151.

[0498] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.172 and preferably less than 0.158 and more preferably less than 0.144.

[0499] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.14 and preferably less than 0.128 and more preferably less than 0.117.

[0500] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.18, and preferably less than or equal to 0.16, and more preferably less than or equal to 0.14.

[0501] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.16, and preferably less than or equal to 0.147, and more preferably less than or equal to 0.134.

[0502] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.151, and preferably less than or equal to 0.138, and more preferably less than or equal to 0.126.

[0503] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.145, and preferably less than or equal to 0.133, and more preferably less than or equal to 0.121.

[0504] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.123, and preferably less than or equal to 0.112, and more preferably less than or equal to 0.102.

[0505] The nvPM emission index ratio of lean-burn cruise to MTO can be less than or equal to 0.157, and preferably less than or equal to 0.144, and more preferably less than or equal to 0.131.

[0506] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.0814, and preferably greater than or equal to 0.0915, and more preferably greater than or equal to 0.101.

[0507] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.096, and preferably greater than or equal to 0.108, and more preferably greater than or equal to 0.12.

[0508] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.0958, and preferably greater than or equal to 0.107, and more preferably greater than or equal to 0.119.

[0509] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.0979 and can preferably be greater than or equal to 0.11 and can more preferably be greater than or equal to 0.122.

[0510] The nvPM emission index ratio of lean-burn cruise to MTO can be greater than or equal to 0.0961, and preferably greater than or equal to 0.108, and more preferably greater than or equal to 0.12.

[0511] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0814 to 0.160, and preferably in the range of 0.0915 to 0.147, and more preferably in the range of 0.101 to 0.134.

[0512] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0814 to 0.151, and preferably in the range of 0.0915 to 0.138, and more preferably in the range of 0.101 to 0.126.

[0513] The nvPM emission index ratio for lean-burn cruise to MTO can be in the range of 0.0960 to 0.151, and preferably in the range of 0.108 to 0.138, and more preferably in the range of 0.120 to 0.126.

[0514] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0958 to 0.160, and preferably in the range of 0.107 to 0.147, and more preferably in the range of 0.119 to 0.134.

[0515] The nvPM emission index ratio for lean-burn cruise to MTO can be in the range of 0.0979 to 0.151, and preferably in the range of 0.110 to 0.138, and more preferably in the range of 0.122 to 0.126.

[0516] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0960 to 0.145, and preferably in the range of 0.108 to 0.133, and more preferably in the range of 0.120 to 0.121.

[0517] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0814 to 0.123, and preferably in the range of 0.0915 to 0.112, and more preferably in the range of 0.101 to 0.102.

[0518] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0961 to 0.160, and preferably in the range of 0.108 to 0.147, and more preferably in the range of 0.120 to 0.134.

[0519] The nvPM emission index ratio for lean-burn cruise flight to MTO can be in the range of 0.0958 to 0.157, and preferably in the range of 0.107 to 0.144, and more preferably in the range of 0.119 to 0.131.

[0520] The nvPM emission index ratio of lean-burn cruise to MTO can be less than 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19 or 0.2, or lie within any range defined by any two of these values.

[0521] BPR can be in the range of 6.44 to 11.2, preferably in the range of 7.25 to 10.3, and particularly preferably in the range of 8.05 to 9.29.

[0522] BPR can be in the range of 7.20 to 11.2 and preferably in the range of 8.10 to 10.3 and particularly preferably in the range of 9.01 to 9.28.

[0523] BPR can be in the range of 7.10 to 11.2 and preferably in the range of 7.99 to 10.3 and particularly preferably in the range of 8.88 to 9.29.

[0524] BPR can be in the range of 7.32 to 11.2 and preferably in the range of 8.23 ​​to 10.3 and particularly preferably in the range of 9.15 to 9.28.

[0525] BPR can be in the range of 7.20 to 10.9, and preferably in the range of 8.10 to 9.92, and particularly preferably in the range of 9.00 to 9.02.

[0526] BPR can be in the range of 6.44 to 9.68 and preferably in the range of 7.25 to 8.87 and particularly preferably in the range of 8.05 to 8.06.

[0527] BPR can be in the range of 7.15 to 11.1 and preferably in the range of 8.04 to 10.2 and particularly preferably in the range of 8.93 to 9.19.

[0528] An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIReiseflug(fett)EImaxTOBPR where: EGG Reiseflug(fett) which can be defined as follows: EI climb + EI approach 2 EGG Steigflugthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions or under other operating conditions; EGG Anflug The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug is calculated; and EGG maxTO The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug is calculated; and where the nvPM emission index ratio of cruise flight with rich combustion to MTO is less than 0.4.

[0529] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.38 and preferably less than 0.36 and more preferably less than 0.34.

[0530] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.323 and preferably less than 0.296 and more preferably less than 0.269.

[0531] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.307 and preferably less than 0.282 and more preferably less than 0.256.

[0532] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.298 and preferably less than 0.273 and more preferably less than 0.248.

[0533] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.277 and preferably less than 0.254 and more preferably less than 0.231.

[0534] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.211 and preferably less than 0.193 and more preferably less than 0.176.

[0535] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.13 and can preferably be less than or equal to 0.119 and can more preferably be less than or equal to 0.108.

[0536] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.129, and preferably less than or equal to 0.119, and more preferably less than or equal to 0.108.

[0537] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.128, and preferably less than or equal to 0.118, and more preferably less than or equal to 0.107.

[0538] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.0823, and preferably less than or equal to 0.0754, and more preferably less than or equal to 0.0686.

[0539] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than or equal to 0.129 and can preferably be less than or equal to 0.118 and can more preferably be less than or equal to 0.108.

[0540] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.0548 and can preferably be greater than or equal to 0.0616 and can more preferably be greater than or equal to 0.0685.

[0541] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.0773 and can preferably be greater than or equal to 0.087 and can more preferably be greater than or equal to 0.0966.

[0542] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.0633 and can preferably be greater than or equal to 0.0712 and can more preferably be greater than or equal to 0.0791.

[0543] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.086 and can preferably be greater than or equal to 0.0968 and can more preferably be greater than or equal to 0.107.

[0544] The nvPM emission index ratio of cruise flight with rich combustion to MTO can be greater than or equal to 0.0676 and can preferably be greater than or equal to 0.0761 and can more preferably be greater than or equal to 0.0845.

[0545] The nvPM emission index ratio for cruise flight with rich combustion to MTO can be in the range of 0.0548 to 0.130 and can preferably be in the range of 0.0616 to 0.119 and can more preferably be in the range of 0.0685 to 0.108.

[0546] The nvPM emission index ratio for cruise flight with rich combustion to MTO can be in the range of 0.0773 to 0.130, and preferably in the range of 0.0870 to 0.119, and more preferably in the range of 0.0966 to 0.108.

[0547] The nvPM emission index ratio for cruise flight with rich combustion to MTO can be in the range of 0.0633 to 0.129 and can preferably be in the range of 0.0712 to 0.119 and can more preferably be in the range of 0.0791 to 0.108.

[0548] The nvPM emission index ratio for cruise flight with rich combustion to MTO can be in the range of 0.0773 to 0.128, and preferably in the range of 0.0870 to 0.118, and more preferably in the range of 0.0966 to 0.107.

[0549] The nvPM emission index ratio for cruise flight with rich combustion to MTO can be in the range of 0.0860 to 0.130 and can preferably be in the range of 0.0968 to 0.119 and can more preferably be in the range of 0.107 to 0.108.

[0550] The nvPM emission index ratio for cruise flight with rich combustion to MTO can be in the range of 0.0548 to 0.0823 and can preferably be in the range of 0.0616 to 0.0754 and can more preferably be in the range of 0.0685 to 0.0686.

[0551] The nvPM emission index ratio for cruise flight with rich combustion to MTO can be in the range of 0.0676 to 0.129, and preferably in the range of 0.0761 to 0.119, and more preferably in the range of 0.0845 to 0.108.

[0552] The nvPM emission index ratio of rich combustion cruise flight to MTO can be less than 0.02, 0.04, 0.06, 0.08, 0.1, 0.12, 0.14, 0.16, 0.18, 0.2, 0.22, 0.24, 0.26, 0.28, 0.3, 0.32, 0.34, 0.36, 0.38, 0.4 or lie within any range defined by any two of these values.

[0553] According to a sixty-second aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIReiseflug(fett)EImaxTOBPR where: EGG Reiseflug(fett) which can be defined as follows: EI climb + EI approach 2 EGG SteigflugThe nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 85% of the available thrust under the given operating conditions; EGG Anflug The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug is calculated; EGG maxTO The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug is calculated; BPR is the bypass ratio of the gas turbine engine; the nvPM emission index ratio of cruise flight with rich combustion to MTO is less than 0.4; and the gas turbine engine is configured to provide fuel to the multiple fuel spray nozzles, including sustainable aviation fuel (SAF).

[0554] The nvPM emission index ratio of cruise flight with rich combustion to MTO and to or the BPR can be defined as above in connection with the twelfth aspect.

[0555] According to a sixty-third aspect, a method for operating the gas turbine engine of the sixty-first or sixty-second aspect is provided, the method comprising the provision of fuel, comprising a sustainable aviation fuel, for the plurality of fuel spray nozzles.

[0556] According to a sixty-fourth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An nvPM emission index ratio for lean-burn cruise flight to MTO can be defined as follows: EIReiseflug(meier)EImaxTOBPR where: EGG Reiseflug (mager) which can be defined as follows: EImaxTO+EISteigflug2 EGG maxTO The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 100% of the available thrust under the given operating conditions; EGG Steigflug the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions; and BPR is the bypass ratio of the gas turbine engine; the nvPM emission index ratio of lean-burn cruise to MTO is less than 0.2; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0557] The nvPM emission index ratio for lean-burn cruise flight to MTO and to or the BPR can be defined as above in connection with the twelfth aspect.

[0558] An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIReiseflug(fett)EImaxTOBPR where: EGG Reiseflug(fett) which can be defined as follows: EI climb + EI approach 2 EGG Steigflug the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of the available thrust under the given operating conditions or under other operating conditions; EGG Anflug The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug is calculated; EGG maxTO The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug is calculated; and where the nvPM emission index ratio of cruise flight with rich combustion to MTO can be less than 0.4.

[0559] The nvPM emission index ratio of cruise flight with rich combustion to MTO and to or the BPR can be defined as above in connection with the twelfth aspect.

[0560] According to a sixty-fifth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An nvPM emission index ratio for cruise flight with rich combustion to MTO can be defined as follows: EIReiseflug(fett)EImaxTOBPR where: EGG Reiseflug(fett) which can be defined as follows: EI climb + EI approach 2 EGG Steigflug The nvPM emission index of the gas turbine engine, corrected for system losses, in mg / kg, is used when operating at approximately 85% of the available thrust under the given operating conditions; EGG AnflugThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Steigflug is calculated; EGG maxTO The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 100% of available thrust under the same operating conditions as those under which EI Steigflug is calculated; BPR is the bypass ratio of the gas turbine engine; the nvPM emission index ratio of cruise flight with rich combustion to MTO is less than 0.4; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0561] The nvPM emission index ratio of cruise flight with rich combustion to MTO and to or the BPR can be defined as above in connection with the twelfth aspect.

[0562] According to a sixty-sixth aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An MTO-nvPM emission index ratio can be defined as follows: EImaxTO,SAFEImaxTO,FF where: EGG maxTO,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that includes sustainable aviation fuel (SAF); and EGG maxTO,FF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 100% of the available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies is a fossil-based hydrocarbon fuel; the MTO-nvPM emission index ratio of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0563] The MTO-nvPM emission index ratio can be greater than zero.

[0564] The MTO-nvPM emission index ratio can be less than or equal to 0.93, can preferably be less than or equal to 0.86, and can more preferably be less than or equal to 0.79.

[0565] The MTO-nvPM emission index ratio can be less than or equal to 0.776, can preferably be less than or equal to 0.711, and can more preferably be less than or equal to 0.646.

[0566] The MTO-nvPM emission index ratio can be greater than or equal to 0.15, can preferably be greater than or equal to 0.3, and can more preferably be greater than or equal to 0.45.

[0567] The MTO-nvPM emission index ratio can be greater than or equal to 0.516, can preferably be greater than or equal to 0.581, and can more preferably be greater than or equal to 0.645.

[0568] The MTO-nvPM emission index ratio can be in the range of 0.516 to 0.776, and preferably in the range of 0.581 to 0.711, and more preferably in the range of 0.645 to 0.646.

[0569] The MTO-nvPM emission index ratio can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0570] The MTO-nvPM emission index ratio can be 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.6, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.68, 0.69, 0.7, 0.71, 0.72, 0.73, 0.74, 0.75, 0.76, 0.77, 0.78, 0.79 or 0.8, or lie within any range defined by any two of these values.

[0571] A climb-nvPM emission index ratio can be defined as follows: ICE Climb, SAFE ICE Climb, FF where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; and where the climb-nvPM emission index ratio of the gas turbine engine can be less than 1.

[0572] The climb-nvPM emission index ratio can be greater than zero.

[0573] The climb-nvPM emission index ratio can be less than or equal to 0.9, can preferably be less than or equal to 0.75, and can more preferably be less than or equal to 0.6.

[0574] The climb-nvPM emission index ratio can be less than or equal to 0.57, can preferably be less than or equal to 0.523, and can more preferably be less than or equal to 0.475.

[0575] The climb-nvPM emission index ratio can be greater than or equal to 0.1, can preferably be greater than or equal to 0.2, and can more preferably be greater than or equal to 0.3.

[0576] The climb-nvPM emission index ratio can be greater than or equal to 0.379, can preferably be greater than or equal to 0.427, and can more preferably be greater than or equal to 0.474.

[0577] The climb-nvPM emission index ratio can be in the range of 0.379 to 0.570, and preferably in the range of 0.427 to 0.523, and more preferably in the range of 0.474 to 0.475.

[0578] The climb-nvPM emission index ratio can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0579] The climb-nvPM emission index ratio can be 0.37, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.6 or within any range defined by any two of these values.

[0580] An approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEI approach, FF where: EGG Anflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Anflug,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 30% of available thrust under the same given operating conditions as those under which EI Anflug,SAF is calculated, and if one of the fuels supplied by the multitude of fuel spray nozzles is a fossil-based hydrocarbon fuel, then; and where the approach nvPM emission index ratio of the gas turbine engine can be less than 1.

[0581] The approach-nvPM emission index ratio can be greater than zero.

[0582] The approach nvPM emission index ratio can be less than or equal to 0.8, can preferably be less than or equal to 0.5, and can more preferably be less than or equal to 0.2.

[0583] The approach nvPM emission index ratio can be less than or equal to 0.185, can preferably be less than or equal to 0.169, and can more preferably be less than or equal to 0.154.

[0584] The approach-nvPM emission index ratio can be greater than or equal to 0.03, can preferably be greater than or equal to 0.06, and can more preferably be greater than or equal to 0.09.

[0585] The approach-nvPM emission index ratio can be greater than or equal to 0.122, can preferably be greater than or equal to 0.138, and can more preferably be greater than or equal to 0.153.

[0586] The approach-nvPM emission index ratio can be in the range of 0.122 to 0.185, and preferably in the range of 0.138 to 0.169, and more preferably in the range of 0.153 to 0.154.

[0587] The approach-nvPM emission index ratio can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0588] The approach-nvPM emission index ratio can be 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2 or within any range defined by any two of these values.

[0589] An idle-nvPM emission index ratio can be defined as follows: EILEerlauf,SAFEILeerlauf,FF where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under the given operating conditions or under other given operating conditions, and if a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and. if the fuel supplied to any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel, then; and where the idle nvPM emission index ratio of the gas turbine engine can be less than 1.

[0590] The idle-nvPM emission index ratio can be greater than zero.

[0591] The idle nvPM emission index ratio can be less than or equal to 0.8, can preferably be less than or equal to 0.5, and can more preferably be less than or equal to 0.2.

[0592] The idle nvPM emission index ratio can be less than or equal to 0.115, can preferably be less than or equal to 0.106, and can more preferably be less than or equal to 0.0959.

[0593] The idle-nvPM emission index ratio can be greater than or equal to 0.02, can preferably be greater than or equal to 0.04, and can more preferably be greater than or equal to 0.06.

[0594] The idle nvPM emission index ratio can be greater than or equal to 0.0766, can preferably be greater than or equal to 0.0862, and can more preferably be greater than or equal to 0.0958.

[0595] The idle-nvPM emission index ratio can be in the range of 0.0766 to 0.115, and preferably in the range of 0.0862 to 0.106, and more preferably in the range of 0.0958 to 0.0959.

[0596] The idle-nvPM emission index ratio can be less than 1, 0.95, 0.9, 0.85, 0.8, 0.75, 0.7, 0.65, 0.6, 0.55, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1 or 0.05, or within any range defined by any two of these values.

[0597] The nvPM emission index ratio at idle can be 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2 or lie within any range defined by any two of these values.

[0598] According to a sixty-seventh aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A climb-to-emissions index ratio can be defined as follows: ICE Climb, SAFE ICE Climb, FF where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAFis calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; the climb-to-nvPM emission index ratio of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0599] The climb-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0600] According to a sixty-eighth aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEI approach, FF where: EGG Anflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Anflug,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 30% of available thrust under the same given operating conditions as those under which EI Anflug,SAF is calculated, and if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, it is; the approach-nvPM emission index ratio of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0601] The approach-nvPM emission index ratio can be defined as above in connection with the sixty-sixth aspect.

[0602] According to a sixty-ninth aspect, a gas turbine engine is provided for an aircraft, comprising one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An idle-nvPM emission index ratio can be defined as follows: EILEerlauf,SAFEILeerlauf,FF where: EGG Leerlauf,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, and if a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and. if the fuel supplied to any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel, then; the idle nvPM emission index ratio of the gas turbine engine is less than 1; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0603] The idle-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0604] According to a seventieth aspect, a method for operating the gas turbine engine is provided according to one of the sixty-sixth, sixty-seventh, sixty-eighth or sixty-ninth aspects, the method comprising the provision of fuel, comprising a sustainable aviation fuel, for the plurality of fuel spray nozzles.

[0605] According to a seventy-first aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An MTO-nvPM emission index ratio can be defined as follows: EImaxTO,SAFEImaxTO,FF where: EGG maxTO,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that includes sustainable aviation fuel (SAF); and EGG maxTO,FF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at 100% of available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies a fossil-based hydrocarbon fuel; the MTO-nvPM emission index ratio of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0606] The MTO-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0607] A climb-nvPM emission index ratio can be defined as follows: ICE Climb, SAFE ICE Climb, FF where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Steigflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; and wherein The climb-nvPM emission index ratio of the gas turbine engine may be less than 1.

[0608] The climb-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0609] An approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEI approach, FF where: EGG Anflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Anflug,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 30% of available thrust under the same given operating conditions as those under which EI Anflug,SAF is calculated, and if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel; and wherein The approach nvPM emission index ratio of the gas turbine engine may be less than 1.

[0610] The approach-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0611] An idle-nvPM emission index ratio can be defined as follows: EILEerlauf,SAFEILeerlauf,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under the given operating conditions or under other given operating conditions, and if a fuel supplied to the multiple fuel spray nozzles includes sustainable aviation fuel (SAF); and EGG Leerlauf,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAFis calculated, and. if the fuel supplied to any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel, then; and where the idle nvPM emission index ratio of the gas turbine engine can be less than 1.

[0612] The idle-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0613] According to a seventy-second aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A climb-to-emissions index ratio can be defined as follows: ICE Climb, SAFE ICE Climb, FF where: EGG Steigflug,SAFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under given operating conditions, where the fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Steigflug,FF The system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated, and, if one of the multiple fuel spray nozzles supplied is a fossil-based hydrocarbon fuel, is; the climb-to-nvPM emission index ratio of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0614] The climb-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0615] According to a seventy-third aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEI approach, FF where: EGG Anflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under given operating conditions, where one of the fuels supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGGAnflug,FF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, during operation at approximately 30% of available thrust under the same given operating conditions as those under which EI Anflug,SAF is calculated, and if one of the fuels supplied by the multitude of fuel spray nozzles is a fossil-based hydrocarbon fuel, then; and the approach-nvPM emission index ratio of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0616] The approach-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0617] According to a seventy-fourth aspect, a method for operating a gas turbine engine is provided, the gas turbine engine comprising: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: An idle-nvPM emission index ratio can be defined as follows: EILEerlauf,SAFEILeerlauf,FF where: EGG Leerlauf,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 7% of available thrust under given operating conditions, and if a fuel supplied to the fuel spray nozzles includes a sustainable aviation fuel (SAF); and EGG Leerlauf,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 7% of available thrust under the same given operating conditions as those under which EI Leerlauf,SAF is calculated, and. if the fuel supplied to any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel, then; and the idle nvPM emission index ratio of the gas turbine engine is less than 1; and The process involves supplying a sustainable aviation fuel to the multitude of fuel spray nozzles.

[0618] The idle-nvPM emission index ratio can be defined as in connection with the sixty-sixth aspect.

[0619] According to a seventy-fifth aspect, a gas turbine engine is provided for an aircraft, which includes one or more of the following elements: a combustion chamber comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber; and wherein: A fuel stream modified with respect to the MTO-nvPM emission index ratio can be defined as follows: EImaxTO,SAFEImaxTO,FF×Wf,maxTO where: EGG maxTO,SAF The nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under given operating conditions, where one of the multiple fuel spray nozzles supplies fuel that includes sustainable aviation fuel (SAF); EGG maxTO,FFthe nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at approximately 100% of available thrust under the given operating conditions, when one of the multiple fuel spray nozzles supplies a fossil-based hydrocarbon fuel; and W f,maxTO the mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 100% of the available thrust under the given operating conditions; the fuel flow of the gas turbine engine, modified with respect to the MTO-nvPM emission index ratio, is less than 5 kg / s; and the gas turbine engine is configured to provide a SAF-comprehensive fuel to the multitude of fuel spray nozzles.

[0620] The fuel flow in kg / s, modified with respect to the MTO-nvPM emission index ratio, can be greater than zero.

[0621] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than 4.2, more preferably less than 3.85 and even more preferably less than 3.5.

[0622] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than 3.39, more preferably less than 3.11 and even more preferably less than 2.82.

[0623] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than 3.45, more preferably less than 3.16 and even more preferably less than 2.88.

[0624] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than 3.13, more preferably less than 2.87 and even more preferably less than 2.61.

[0625] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than 3.01, more preferably less than 2.76 and even more preferably less than 2.51.

[0626] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than or equal to 2.72, more preferably less than or equal to 2.49 and even more preferably less than or equal to 2.26.

[0627] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than or equal to 2.19, more preferably less than or equal to 2.01 and even more preferably less than or equal to 1.83.

[0628] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than or equal to 2.23, more preferably less than or equal to 2.05 and even more preferably less than or equal to 1.86.

[0629] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than or equal to 2.02, more preferably less than or equal to 1.85 and even more preferably less than or equal to 1.69.

[0630] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be less than or equal to 1.94, more preferably less than or equal to 1.78 and even more preferably less than or equal to 1.62.

[0631] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be greater than or equal to 1.45, more preferably greater than or equal to 1.63 and even more preferably greater than or equal to 1.82.

[0632] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be greater than or equal to 1.08, more preferably greater than or equal to 1.22 and even more preferably greater than or equal to 1.36.

[0633] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be greater than or equal to 1.24, more preferably greater than or equal to 1.4 and even more preferably greater than or equal to 1.55.

[0634] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be greater than or equal to 1.8, more preferably greater than or equal to 2.03 and even more preferably greater than or equal to 2.25.

[0635] The fuel flow rate in kg / s modified with respect to the MTO-nvPM emission index ratio can be greater than or equal to 1.18, more preferably greater than or equal to 1.33 and even more preferably greater than or equal to 1.47.

[0636] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.08 to 2.72, preferably in the range of 1.22 to 2.49 and more preferably in the range of 1.36 to 2.26.

[0637] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.24 to 2.72, preferably in the range of 1.40 to 2.49 and more preferably in the range of 1.55 to 2.26.

[0638] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.24 to 2.19, preferably in the range of 1.40 to 2.01 and more preferably in the range of 1.55 to 1.83.

[0639] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.08 to 2.23, preferably in the range of 1.22 to 2.05 and more preferably in the range of 1.36 to 1.86.

[0640] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.24 to 2.02, preferably in the range of 1.40 to 1.85 and more preferably in the range of 1.55 to 1.69.

[0641] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.45 to 2.19, preferably in the range of 1.63 to 2.01 and more preferably in the range of 1.82 to 1.83.

[0642] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.80 to 2.72, preferably in the range of 2.03 to 2.49 and more preferably in the range of 2.25 to 2.26.

[0643] The fuel flow rate modified with respect to the MTO-nvPM emission index ratio in kg / s can be in the range of 1.18 to 1.94, preferably in the range of 1.33 to 1.78 and more preferably in the range of 1.47 to 1.62.

[0644] The fuel flow modified with respect to the MTO-nvPM emission index ratio in kg / s is 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.25, 2.5, 2.75, 3, 3.25, 3.5, 3.75, 4, 4.25, 4.5, 4.75, 5 or in any range between any two of these values.

[0645] W f,maxTO The value in kg / s can be in the range of 1.68 to 4.20 and preferably in the range of 1.89 to 3.85 and particularly preferably in the range of 2.10 to 3.50.

[0646] W f,maxTO The value in kg / s can be in the range of 1.92 to 4.20 and preferably in the range of 2.16 to 3.85 and particularly preferably in the range of 2.41 to 3.50.

[0647] W f,maxTOThe value in kg / s can be in the range of 1.92 to 3.39 and preferably in the range of 2.16 to 3.11 and particularly preferably in the range of 2.41 to 2.82.

[0648] W f,maxTO in kg / s can be in the range of 1.68 to 3.45 and preferably in the range of 1.89 to 3.16 and particularly preferably in the range of 2.10 to 2.88.

[0649] W f,maxTO The value in kg / s can be in the range of 1.92 to 3.13 and preferably in the range of 2.16 to 2.87 and particularly preferably in the range of 2.41 to 2.61.

[0650] W f,maxTO in kg / s can be in the range of 2.25 to 3.39 and preferably in the range of 2.53 to 3.11 and particularly preferably in the range of 2.81 to 2.82.

[0651] W f,maxTO in kg / s can be in the range of 2.79 to 4.20 and preferably in the range of 3.14 to 3.85 and particularly preferably in the range of 3.49 to 3.50.

[0652] W f,maxTOin kg / s can be in the range of 1.83 to 3.01 and preferably in the range of 2.05 to 2.76 and particularly preferably in the range of 2.28 to 2.51.

[0653] W f,maxTO in kg / s can be in the range of 1.68 to 3.45 and preferably in the range of 1.89 to 3.16 and particularly preferably in the range of 2.10 to 2.88.

[0654] A fuel flow modified with respect to the climb-nvPM emission index ratio can be defined as follows: EISclimb,SAFEISclimb,FF×Wf,climb where: EGG Steigflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 85% of available thrust under the given operating conditions, or under other given operating conditions where a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Steigflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 85% of available thrust under the same given operating conditions as those under which EI Steigflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Steigflug the mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 85% of the available thrust under the same operating conditions as those in which EI Steigflug,SAF and egg Steigflug,FF to be calculated; and where The fuel flow rate of the gas turbine engine, modified with respect to the climb-nvPM emission index ratio, may be less than 4 kg / s.

[0655] The fuel flow in kg / s modified with respect to the climb-nvPM emission index ratio can be greater than zero.

[0656] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than 3.36, more preferably less than 3.08 and even more preferably less than 2.8.

[0657] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than 2.77, more preferably less than 2.54 and even more preferably less than 2.31.

[0658] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than 2.79, more preferably less than 2.56 and even more preferably less than 2.33.

[0659] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than 2.56, more preferably less than 2.35 and even more preferably less than 2.13.

[0660] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than 2.45, more preferably less than 2.25 and even more preferably less than 2.04.

[0661] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than or equal to 1.6, more preferably less than or equal to 1.47 and even more preferably less than or equal to 1.33.

[0662] The fuel flow in kg / s modified with respect to the climb-nvPM emission index ratio can be less than or equal to 1.32, more preferably less than or equal to 1.21 and even more preferably less than or equal to 1.1.

[0663] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than or equal to 1.33, more preferably less than or equal to 1.22 and even more preferably less than or equal to 1.11.

[0664] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than or equal to 1.22, more preferably less than or equal to 1.12 and even more preferably less than or equal to 1.02.

[0665] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be less than or equal to 1.17, more preferably less than or equal to 1.07 and even more preferably less than or equal to 0.969.

[0666] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be greater than or equal to 0.658, more preferably greater than or equal to 0.74 and even more preferably greater than or equal to 0.822.

[0667] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be greater than or equal to 0.751, more preferably greater than or equal to 0.845 and even more preferably greater than or equal to 0.939.

[0668] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be greater than or equal to 0.876, more preferably greater than or equal to 0.985 and even more preferably greater than or equal to 1.09.

[0669] The fuel flow rate in kg / s modified with respect to the climb-nvPM emission index ratio can be greater than or equal to 1.06, more preferably greater than or equal to 1.19 and even more preferably greater than or equal to 1.32.

[0670] The climb-nvPM emission index ratio can be greater than or equal to 0.712, can preferably be greater than or equal to 0.801, and can more preferably be greater than or equal to 0.89.

[0671] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.658 to 1.60, preferably in the range of 0.740 to 1.47 and more preferably in the range of 0.822 to 1.33.

[0672] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.751 to 1.60, preferably in the range of 0.845 to 1.47 and more preferably in the range of 0.939 to 1.33.

[0673] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.751 to 1.32, preferably in the range of 0.845 to 1.21 and more preferably in the range of 0.939 to 1.10.

[0674] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.658 to 1.33, preferably in the range of 0.740 to 1.22 and more preferably in the range of 0.822 to 1.11.

[0675] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.751 to 1.22, preferably in the range of 0.845 to 1.12 and more preferably in the range of 0.939 to 1.02.

[0676] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.876 to 1.32, preferably in the range of 0.985 to 1.21 and more preferably in the range of 1.09 to 1.10.

[0677] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 1.06 to 1.60, preferably in the range of 1.19 to 1.47 and more preferably in the range of 1.32 to 1.33.

[0678] The fuel flow rate in kg / s, modified with respect to the climb-nvPM emission index ratio, can be in the range of 0.712 to 1.17, preferably in the range of 0.801 to 1.07 and more preferably in the range of 0.890 to 0.969.

[0679] The climb-nvPM emission index ratio and the modified fuel flow can be 0.2, 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, 2.8, 3, 3.2, 3.4, 3.6, 3.8, 4 or in any range between any two of these values.

[0680] W f,Steigtlug The value in kg / s can be in the range of 1.38 to 3.36 and preferably in the range of 1.55 to 3.08 and particularly preferably in the range of 1.73 to 2.80.

[0681] W f,steigflugin kg / s can be in the range of 1.58 to 3.36 and preferably in the range of 1.78 to 3.08 and particularly preferably in the range of 1.97 to 2.80.

[0682] W f,Steigflug in kg / s can be in the range of 1.58 to 2.77 and preferably in the range of 1.78 to 2.54 and particularly preferably in the range of 1.97 to 2.31.

[0683] W f,Steigflug The value in kg / s can be in the range of 1.38 to 2.79 and preferably in the range of 1.55 to 2.56 and particularly preferably in the range of 1.73 to 2.33.

[0684] W f,Steigflug in kg / s can be in the range of 1.58 to 2.56 and preferably in the range of 1.78 to 2.35 and particularly preferably in the range of 1.97 to 2.13.

[0685] W f,Steigflug in kg / s can be in the range of 1.84 to 2.77 and preferably in the range of 2.07 to 2.54 and particularly preferably in the range of 2.30 to 2.31.

[0686] W f,Steigflugin kg / s can be in the range of 2.23 to 3.36 and preferably in the range of 2.51 to 3.08 and particularly preferably in the range of 2.79 to 2.80.

[0687] W f,Steigflug The value in kg / s can be in the range of 1.50 to 2.45 and preferably in the range of 1.68 to 2.25 and particularly preferably in the range of 1.87 to 2.04.

[0688] A fuel flow modified with respect to the approach-nvPM emission index ratio can be defined as follows: EI approach, SAFEIA approach, FF×Wf, approach where: EGG Anflug,SAF the nvPM emission index of the gas turbine engine in mg / kg, corrected for system losses, at operation with approximately 30% of available thrust under the given operating conditions or under other operating conditions, if a fuel supplied to the multiple fuel spray nozzles includes a sustainable aviation fuel; and EGG Anflug,FFThe system loss-corrected nvPM emission index of the gas turbine engine in mg / kg at operation with approximately 30% of the available thrust under the same operating conditions as those under which EI Anflug,SAF is calculated when the fuel supplied by any of the multiple fuel spray nozzles is a fossil-based hydrocarbon fuel; and W f,Anflug the mass flow rate of the fuel supplied to the multitude of fuel spray nozzles in kg / s when the gas turbine engine is operated at approximately 30% of the available thrust under the same operating conditions as those in which EI Anflug,SAF and egg Anflug,FF to be calculated; and where The fuel flow of the gas turbine engine, modified with respect to the approach nvPM emission index ratio, may be less than 2 kg / s.

[0689] The fuel flow in kg / s, modified with respect to the approach-nvPM emission index ratio, can be greater than zero.

[0690] The fuel flow in kg / s modified with respect to the approach-nvPM emission index ratio can be less than 1.11, more preferably less than 1.01 and even more preferably less than 0.919.

[0691] The fuel flow in kg / s modified with respect to the approach-nvPM emission index ratio can be less than 0.96...

Claims

[1] Gas turbine engine (10) for an aircraft, comprising: a combustion chamber (16) comprising a combustion chamber (120) and a plurality of fuel spray nozzles (124) configured to inject fuel into the combustion chamber (120), wherein the plurality of fuel spray nozzles (124) comprises a first subset (124A) of fuel spray nozzles (124) and a second subset (124B) of fuel spray nozzles (124), wherein the combustion chamber (16) is operable in a state in which each of the fuel spray nozzles of the first subset (124A) of fuel spray nozzles (124) is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset (124B) of fuel spray nozzles (124), wherein the number of fuel spray nozzles (124) in the first subset (124A) of fuel spray nozzles (124) to the number of fuel spray nozzles (124) in the second subset (124B) of fuel spray nozzles (124) in the range of 1:3 to 1:6; and where: A thrust-nvPM emission index ratio is defined as follows: EImaxTOFmaxTOEIIdleIdleIdle where: EGG Leerlauf the nvPM emission index of the gas turbine engine (10) in mg / kg corrected for system losses at operation with approximately 7% of the available thrust under given operating conditions; EGG maxTO the nvPM emission index in mg / kg of the gas turbine engine (10) corrected for system losses at operation with approximately 100% of the available thrust under the given operating conditions; F maxTO the thrust of the gas turbine engine (10) is approximately 100% of the available thrust in kN under the given operating conditions; and F Leerlauf the thrust of the gas turbine engine (10) is at approximately 7% of the available thrust in kN under the given operating conditions; the thrust-nvPM emission index ratio is greater than 0.02 and the gas turbine engine (10) is configured to supply the multiple fuel spray nozzles (124) with a fuel that includes sustainable aviation fuel (SAF). [2] Gas turbine engine (10) according to claim 1, wherein the thrust-nvPM emission index ratio is greater than 0.0264 and preferably greater than 0.0297 and more preferably greater than 0.

033. [3] Gas turbine engine (10) according to claim 1 or claim 2, wherein the thrust-nvPM emission index ratio is greater than 0.0312 and preferably greater than 0.0351 and more preferably greater than 0.

039. [4] Gas turbine engine (10) according to one of the preceding claims, wherein the thrust-nvPM emission index ratio is greater than or equal to 0.07 and preferably greater than or equal to 0.1 and more preferably greater than or equal to 0.

13. [5] Gas turbine engine (10) according to one of the preceding claims, wherein the thrust-nvPM emission index ratio is greater than or equal to 0.178 and preferably greater than or equal to 0.2 and more preferably greater than or equal to 0.

223. [6] Gas turbine engine (10) according to one of the preceding claims, wherein the thrust-nvPM emission index ratio is greater than or equal to 0.21 and preferably greater than or equal to 0.237 and more preferably greater than or equal to 0.

263. [7] Gas turbine engine (10) according to one of the preceding claims, wherein the thrust-nvPM emission index ratio is less than or equal to 0.365 and preferably less than or equal to 0.335 and more preferably less than or equal to 0.

304. [8] Gas turbine engine (10) according to one of the preceding claims, wherein the thrust-nvPM emission index ratio is less than or equal to 0.317 and preferably less than or equal to 0.29 and more preferably less than or equal to 0.

264. [9] Gas turbine engine (10) according to any one of the preceding claims, wherein: a) F maxTO in the range of 204 kN to 420 kN and preferably in the range of 229 kN to 385 kN and more, preferably in the range of 255 kN to 350 kN and / or b) F Leerlauf in the range of 14.2 kN to 29.4 kN and preferably in the range of 16.0 kN to 26.9 kN and more preferably in the range of 17.8 kN to 24.5 kN. [10] Gas turbine engine (10) according to one of the preceding claims, wherein the ratio of the number of fuel spray nozzles (124) in the first subset (124A) of the fuel spray nozzles (124) to the number of fuel spray nozzles (124) in the second subset (124B) of the fuel spray nozzles (124) is in the range of 1:4 to 1:5 or preferably in the range of 1:4.25 to 1:4.

75. [11] Gas turbine engine (10) according to one of the preceding claims, wherein the combustion chamber (16) comprises one or more igniters (126). [12] Gas turbine engine (10) according to claim 11, wherein each of the first subset (124A) of the fuel spray nozzles (124) is arranged closer to one or more of the igniters (126) than the second subset (124B) and / or wherein one or more of the igniters (126) is / are arranged diametrically opposite one or more of the other igniters (126). [13] Gas turbine engine (10) according to one of the preceding claims, wherein the fuel supplied to the combustion chamber (16) comprises a SAF percentage in the range of 50% to 100%, preferably in the range of 70% to 100% and more, preferably in the range of 90% to 100%. [14] Method (1000) for operating the gas turbine engine (10) according to one of the preceding claims, wherein the method comprises providing (1002) fuel comprising a sustainable aviation fuel to the plurality of fuel spray nozzles (124). [15] Method (1000) for operating a gas turbine engine (10), wherein the gas turbine engine (10) comprises: a combustion chamber (16) comprising a combustion chamber (120) and a plurality of fuel spray nozzles (124) configured to inject fuel into the combustion chamber (120), wherein the plurality of fuel spray nozzles (124) comprises a first subset (124A) of fuel spray nozzles (124) and a second subset (124B) of fuel spray nozzles (124), wherein the combustion chamber (16) is operable in a state in which each of the fuel spray nozzles of the first subset (124A) of fuel spray nozzles (124) is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset (124B) of fuel spray nozzles (124), wherein the number of fuel spray nozzles (124) in the first subset (124A) of fuel spray nozzles (124) to the number of fuel spray nozzles (124) in the second subset (124B) of fuel spray nozzles (124) in the range of 1:3 to 1:6; and where: A thrust-nvPM emission index ratio is defined as follows: EImaxTOFmaxTOEIIdleIdleIdle where: EGG Leerlauf the nvPM emission index of the gas turbine engine (10) in mg / kg, corrected for system losses, at operation with approximately 7% of the available thrust under given operating conditions; and EGG maxTO the nvPM emission index in mg / kg of the gas turbine engine (10) corrected for system losses at operation with approximately 100% of the available thrust under the given operating conditions; F maxTO The thrust of the gas turbine engine (10) at approximately 100% of the available thrust in kN under the given operating conditions is F Leerlauf the thrust of the gas turbine engine (10) is at approximately 7% of the available thrust in kN under the given operating conditions and the thrust-nvPM emission index ratio is greater than 0.02 and the process comprises the provision (1002) of fuel comprising a sustainable aviation fuel to the plurality of fuel spray nozzles (124).

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