Emergency fuel oil drainage system for airplane

Abstract

An aircraft fuel emergency oil drainage system is applied to a three-tank configuration fuel system comprising a wing oil tank and a central oil tank, and the wing oil tank is provided with an oil supply pump for supplying oil to an aircraft engine; the emergency oil drainage system comprises a central oil tank emergency oil drainage device and a wing oil tank emergency oil drainage device, the central oil tank emergency oil drainage device comprises a central oil tank emergency oil drainage pump, and the oil drainage pump is connected to an emergency oil drainage main pipeline leading to the outside of the aircraft body. The emergency oil drainage device for the wing oil tank comprises a jet pump and an emergency oil drainage branch, the jet pump comprises an inlet, an outlet and a suction inlet, the inlet is connected to an engine oil supply pump, and the outlet is connected to the emergency oil drainage branch to discharge fuel oil from the wing oil tank. The lowest mounting height of the suction inlet relative to the bottom of the wing fuel tank corresponds to the safe fuel level required by flight of the aircraft, and the fuel level can ensure that the aircraft is not overweight during safe landing and an engine has enough power. The invention further relates to an emergency oil drainage method adopting the system.

Description

Technical Field

[0001] This application relates to an aircraft fuel system, and particularly to an aircraft fuel emergency fuel dumping system and method. Background Art

[0002] As one of the subsystems of the aircraft fuel system, the emergency fuel dumping system can discharge fuel outside the aircraft body in case of an emergency in the air, so as to quickly reduce the aircraft weight to the maximum landing weight or a set lower weight when the aircraft has a fault just after takeoff and other extreme situations that require landing, enabling the aircraft to return to land with sufficient safety level.

[0003] In the forward design process of the aircraft emergency fuel dumping system, it is found that the realization of the emergency fuel dumping function is not difficult, and the difficulty lies in ensuring the safety of emergency fuel dumping. On the one hand, fuel needs to be quickly discharged after the flight crew makes a decision. On the other hand, it is necessary to ensure that when the target fuel quantity is reached, the emergency fuel dumping system can stop working in time. The inability to stop emergency fuel dumping is an extremely dangerous mechanical failure scenario, and certain measures need to be taken to prevent the emergency fuel dumping system from reducing the fuel on the aircraft to a dangerous quantity.

[0004] Currently, large aircraft generally adopt a three-tank fuel system composed of a left wing tank, a central tank, and a right wing tank. Among them, the proportion of the fuel quantity in the central tank far exceeds that of the wing tanks. Therefore, in terms of emergency fuel dumping efficiency, the flow rate of emergency fuel dumping is mainly provided by the central tank, and the emergency fuel dumping flow rate of the wing tanks is relatively small. Generally, there are strict requirements for the emergency fuel dumping rate of the central tank (such as 1200 kg / min), and the emergency fuel dumping rate of the wing tanks is relatively low, and it is even only required to have the emergency fuel dumping function. From the perspective of ensuring fuel supply safety, to prevent the emergency fuel dumping system from reducing the fuel on the aircraft to an unacceptable dangerous quantity is essentially to prevent the emergency fuel dumping system from reducing the fuel in the wing tanks to an unacceptable dangerous quantity.

[0005] In the prior art, two mainstream fuel dumping methods have been formed: an independent emergency fuel pump and a reused engine fuel pump in the wing tank.

[0006] For example, an independent emergency fuel pump is provided in the wing tank of a fuel system. During flight, the emergency fuel dumping system is started, and the emergency fuel dumping valve is opened. The emergency fuel pump in the central tank starts to work, and at the same time, the emergency isolation valve is opened so that the override / emergency fuel pump in the central tank supplies fuel to the refueling / emergency fuel dumping main pipe. The fuel in the refueling / emergency fuel dumping pipeline flows out of the aircraft through the opened emergency fuel dumping valve and the emergency fuel dumping port. When the fuel dumping reaches the preset fuel quantity, the fuel dumping process can be stopped. On the ground, regardless of how the switch is operated, the emergency fuel nozzle cut-off valve is always in the closed position, which can prevent the fuel in the fuel tank from accidentally flowing out through the emergency fuel dumping system during maintenance.

[0007] For another example, in a fuel system, no dedicated emergency fuel pump is provided. Instead, the overboard pump in the center wing tank and the main fuel supply pump in the wing tank are used for emergency fuel dumping. When the wing tank fuel drain / emergency fuel drain valve is opened, the main fuel pump in the wing tank is connected to the fuel drain pipeline. When the center tank fuel drain / emergency fuel drain valve is opened, they connect the center tank fuel pump to the refueling pipeline. When the emergency fuel drain cut-off valve is opened, fuel can be discharged into the atmosphere through the refueling pipeline and the emergency fuel drain pipeline.

[0008] In summary, it can be understood that the existing emergency fuel drain system for wing tanks has the following deficiencies: The design of setting up an independent emergency fuel pump in the wing tank adds an extra piece of equipment, which increases the operating cost of the aircraft in terms of weight and subsequent maintenance. The existing technologies only start from the control logic aspect to avoid the problem of excessive fuel dumping, and cannot fundamentally solve the potential risk of excessive fuel dumping. Moreover, the existing high-integration configuration emergency fuel drain system also increases the complexity of the system fuel supply performance matching. Summary of the Invention

[0009] The present application aims to provide an aircraft fuel emergency drain system, which is based on the transfer configuration of the aircraft, can reliably control the potential risk of excessive fuel dumping, and does not increase the operating cost of the aircraft.

[0010] To this end, the present application provides an aircraft fuel emergency drain system. The emergency drain system is applied to a three-tank configuration fuel system including a wing tank and a center tank. A fuel supply pump is provided in the wing tank to supply fuel to the aircraft engine. Among them, the emergency drain system includes a center tank emergency drain device and a wing tank emergency drain device. The center tank emergency drain device includes a center tank emergency fuel pump, and the center tank emergency fuel pump is connected to an emergency drain main pipeline leading to the outside of the aircraft body. Among them: The wing tank emergency drain device includes an ejector pump and an emergency drain branch. The ejector pump includes an inlet, an outlet, and a suction port. The inlet is connected to the engine fuel supply pump, the outlet is connected to the emergency drain branch to discharge fuel from the wing tank, and the suction port is set such that the lowest installation height relative to the bottom of the wing tank corresponds to the safe fuel level required for aircraft flight, which can ensure that the aircraft does not overweight when landing safely and can also ensure that the engine has sufficient power.

[0011] According to the aircraft fuel emergency drain system as described above, when applied to an aircraft, in addition to the traditional control logic for emergency fuel quantity, a mechanical structure guarantee is added for aircraft emergency fuel draining, improving the reliability of stopping emergency fuel draining. The present application uses an ejector pump (jet pump), a mechanical component, which will not significantly increase the weight on the aircraft and can significantly reduce the subsequent maintenance and operating cost of the aircraft.

[0012] Preferably, the emergency drain branch is connected to the emergency drain main pipeline.

[0013] Preferably, the emergency fuel drain branch is connected to the central fuel tank.

[0014] Preferably, an emergency fuel drain isolation valve is further provided between the ejector pump and the fuel supply pump.

[0015] Preferably, a check valve is provided on the emergency fuel drain branch between the ejector pump and the emergency fuel drain main pipeline.

[0016] Preferably, the wing fuel tank includes a left wing fuel tank and a right wing fuel tank. Semi-sealed ribs are respectively provided in the left wing fuel tank and the right wing fuel tank. The left wing fuel tank is divided into a left wing fuel collecting tank area and an outer part of the left wing fuel tank by the semi-sealed rib, and the right wing fuel tank is divided into a right wing fuel collecting tank area and an outer part of the right wing fuel tank by the semi-sealed rib; the ejector pumps are respectively located in the outer parts of the left wing fuel tank and the right wing fuel tank.

[0017] Preferably, the wing fuel tank includes a left wing fuel tank and a right wing fuel tank. Semi-sealed ribs are respectively provided in the left wing fuel tank and the right wing fuel tank. The left wing fuel tank is divided into a left wing fuel collecting tank area and an outer part of the left wing fuel tank by the semi-sealed rib, and the right wing fuel tank is divided into a right wing fuel collecting tank area and an outer part of the right wing fuel tank by the semi-sealed rib; the ejector pumps are respectively located in the left wing fuel collecting tank and the right wing fuel collecting tank.

[0018] Preferably, an emergency fuel drain nozzle is provided at the end of the emergency fuel drain main pipeline, and the fuel is discharged out of the aircraft body through the emergency fuel drain nozzle.

[0019] The present application also provides a method for performing emergency fuel drain by using the aircraft fuel emergency fuel drain system as described above. Among them: the fuel supply pump in the wing fuel tank provides dynamic flow to the ejector pump; the ejector pump sucks the fuel in the wing fuel tank through its suction port and enters the emergency fuel drain branch through the outlet of the ejector pump; when the fuel in the wing fuel tank is lower than the suction port, that is, when the fuel volume has dropped to a level that can not only ensure that the aircraft does not overweight during safe landing but also ensure that the engine has sufficient power, the suction port is exposed above the fuel level, and the dynamic flow supplied to the ejector pump directly discharges from the suction port, and the fuel in the wing fuel tank stops entering the emergency fuel drain branch, and the emergency fuel drain stops.

[0020] Preferably, the fuel from the emergency fuel drain branch enters the emergency fuel drain main pipeline or the central fuel tank. Description of the Drawings

[0021] By reading the following description which is given only by way of illustration and not limitation, other features and advantages of the present application will now become apparent. The description is accompanied by:

[0022] Figure 1It is a configuration diagram of an aircraft fuel system with a three-tank configuration, including the emergency fuel dumping system of the present application.

[0023] Figure 2 It is similar to Figure 1 a configuration diagram of an aircraft fuel system, including Figure 1 Variant Example 1 of the emergency fuel dumping system shown.

[0024] Figure 3A and Figure 3B It is Figures 1-2 an enlarged view of the installation location of the ejector pump of the emergency fuel dumping system of the present application shown.

[0025] List of Reference Signs

[0026] Left wing fuel tank I

[0027] Right wing fuel tank II

[0028] Center fuel tank III

[0029] Aircraft center line AA

[0030] Left wing fuel collector tank area R

[0031] Right wing fuel collector tank area R’

[0032] Outer part P of the left wing fuel tank

[0033] Outer part P’ of the right wing fuel tank

[0034] Semi-sealed ribs 1, 1’

[0035] Engine fuel supply pumps 21, 22, 23, 24

[0036] Center fuel tank emergency fuel dumping pumps 25, 26

[0037] Emergency fuel dumping main pipeline 3

[0038] Emergency fuel dumping nozzles 4, 4’

[0039] Ejector pumps 5, 5’

[0040] Ejector pump inlets 51, 51’

[0041] Ejector pump outlets 52, 52’

[0042] Ejector pump suction inlets 53, 53’

[0043] Emergency fuel dumping isolation valves 6, 6’

[0044] Check valves 7, 7’

[0045] Emergency fuel dumping branch pipelines 8, 8’ connected to the emergency fuel dumping main pipeline 3

[0046] Emergency fuel drain branches 9, 9' connected to the central fuel tank III

[0047] The safe fuel level H' can not only ensure that the aircraft is not overweight when landing safely, but also ensure that the engine has sufficient power

[0048] Specific implementation manners

[0049] To make the above objects, features and advantages of the present application more obvious and understandable, the specific implementation manners of the present application will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0050] It should be noted that when a component is referred to as "connected to" or "disposed on" another component, it can be directly on the other component or there may also be an intermediate component. When a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be intermediate components at the same time. The terms "left" and "right" used in the specification of the present application are the wing orientations when observing the drawing face directly, and "central" corresponds to the part of the center line of the aircraft fuselage. And similar expressions are only for the purpose of illustration and do not represent the only implementation manner.

[0051] Unless otherwise defined, the technical terms or scientific terms used in the claims and the specification should have the ordinary meanings understood by those of ordinary skill in the technical field to which the present application belongs. The words such as "a" or "one" used in the specification and claims of the present application do not indicate a quantity limitation, but mean that there is at least one.

[0052] For an aircraft with a maximum takeoff weight far exceeding the maximum landing weight, in order to ensure that even in extreme situations such as a failure occurring during the takeoff of the aircraft, if the aircraft needs to have sufficient climb ability or ensure an emergency return landing, an emergency fuel drain system needs to be provided to quickly drain the excess fuel out of the aircraft body in an emergency. Usually, after the flight crew makes a decision, the fuel is quickly drained, and at the same time, it is necessary to ensure that the emergency fuel drain system can stop working in time when the target fuel quantity is reached.

[0053] Such as Figure 1 ​As shown, the aircraft fuel system to which the present application is applied is generally a three-tank configuration, including a left-wing tank I, a right-wing tank II, and a central tank III. Semi-sealed ribs 1 and 1' (schematically shown by double dashed lines in the figure) are respectively provided in the regions of the left and right wing tanks close to the aircraft center line AA, so as to divide the left-wing tank I into a left-wing sump region R and an outer part P of the left-wing tank, and a right-wing sump region R' and an outer part P' of the right-wing tank.

[0054] Engine supply pumps 21, 22, 23, and 24 are respectively arranged in the left sump region R and the right sump region R'. These supply pumps are used to supply fuel to the left-wing engine E and the right-wing engine E'. As is known to those skilled in the art, the sump can ensure that the aircraft fuel can effectively collect fuel in various flight attitudes and stably supply fuel to the engine by the supply pump.

[0055] For one of the subsystems of the aircraft fuel system with a three-tank configuration, the emergency fuel dumping system generally includes emergency fuel dumping of the central tank and emergency fuel dumping devices for the wing tanks. As Figure 1 shown, the central tank III includes central tank emergency fuel dumping pumps 25 and 26. Although two fuel dumping pumps are shown in the figure, it is also possible to have one or more fuel dumping pumps according to the setting. The central tank emergency fuel dumping pumps 25 and 26 are connected to an emergency fuel dumping main pipeline 3. Emergency fuel dumping nozzles 4 and 4' are respectively provided at both ends of the main pipeline 3. When a fuel dumping instruction is received, the fuel in the central tank III can be discharged outside the aircraft body. The emergency fuel dumping device for the wing tanks includes an emergency fuel dumping branch for discharging the fuel outside the wing tanks.

[0056] Combined with Figure 1 and Figure 3A 、 3B shown, in the present application, the emergency fuel dumping device for the wing tanks further includes an ejector pump 5, which is also called a jet pump. The inlet 51 of the ejector pump 5 is connected to the engine supply pump 21, and the outlet 52 is connected to the emergency fuel dumping main pipeline 3 through the emergency fuel dumping branch 8. Although Figure 1In the illustrated embodiment, the inlet 51 of the ejector pump 5 is connected to the engine fuel supply pump 21. However, those skilled in the art can understand that the inlet 51 can also be alternatively connected to the engine fuel supply pump 22. Since the ejector pump 5 is connected to the engine fuel supply pump 21 or 22, the engine fuel supply pump 21 or 22 provides motive flow to the ejector pump 5. Similarly, in the right-wing fuel tank II, the inlet 51' of the ejector pump 5' is connected to the engine fuel supply pump 23 or 24, and the outlet 52' is connected to the emergency fuel discharge main pipeline 3 through the emergency fuel discharge branch pipeline 8', and the engine fuel supply pump 23 or 24 provides motive flow to the ejector pump 51'. In the illustrated embodiment, the ejector pump 5 is arranged at the outer part P of the left-wing fuel tank. However, those skilled in the art can also understand that the ejector pump 5 can also be arranged within the left-wing fuel collector region R. Similarly, the ejector pump 5' is arranged at the outer part P' of the right-wing fuel tank as shown in the figure. However, those skilled in the art can also understand that the ejector pump 5' can also be arranged within the right-wing fuel collector region R'.

[0057] More specifically, as Figure 3A and Figure 3B shown, the figure shows Figures 1-2 an enlarged view of the installation position of the ejector pump of the emergency fuel discharge system of the present application. It can be seen therefrom that in addition to the inlet 51 and the outlet 52 described above, the ejector pump 5 further includes a suction port 53. When the ejector pump 5 is connected to the engine fuel supply pump 21 or 22, the installation height X1 of its suction port 53 relative to the fuel tank bottom in the left-wing fuel tank I corresponds to the required safe fuel level H'. The safe fuel level refers to the level that can ensure that the aircraft does not overweight during a safe landing and can also ensure that the engine has sufficient power. The installation height X1 should be higher than the safe fuel level H'. Similarly, in addition to the inlet 51' and the outlet 52' described above, the ejector pump 5' further includes a suction port 53'. When the ejector pump 5' is connected to the engine fuel supply pump 23 or 24, the lowest height of its suction port 53' relative to the fuel tank bottom in the right-wing fuel tank II corresponds to the required safe fuel level, which can ensure that the aircraft does not overweight during a safe landing and can also ensure that the engine has sufficient power. According to the above settings, when the fuel discharge operation cannot be stopped, when the fuel quantity on the aircraft has dropped to the fuel tank liquid level H' as Figure 3B shown, the suction ports 53 and 53' of the ejector pump are exposed above the liquid level, and the motive flow of the ejector pumps 5 and 5' will directly flow out from the suction ports 53 and 53'. The emergency fuel discharge processes of the left-wing fuel tank I and the right-wing fuel tank I will automatically be forced to stop to prevent the risk of excessive fuel discharge from the fuel tanks on the aircraft.

[0058] In practical applications, since the performance of the emergency fuel pump of the central fuel tank III often far exceeds that of the ejector pump, the central fuel tank and the wing fuel tank can be used alternately for emergency fuel discharge, that is, first perform the emergency fuel discharge of the central fuel tank. If the amount of fuel discharged does not reach the required amount, then start the emergency fuel discharge of the wing fuel tank. And due to the existence of the emergency fuel discharge setting of the wing fuel tank in this application, the risk of excessive fuel discharge in the on-board fuel tank can be effectively prevented. Of course, those skilled in the art can also understand that in a particularly urgent situation, the central fuel tank and the wing fuel tank can be used for fuel discharge simultaneously. And in this case, due to the existence of the emergency fuel discharge setting of the wing fuel tank in this application, the risk of excessive fuel discharge in the on-board fuel tank can also be effectively prevented.

[0059] Through the above combination Figure 1 and Figure 3A 、 3B the characteristics and functions of the emergency fuel discharge system of this application have been described. And those skilled in the art can thus understand that compared with the prior art of using the reused wing fuel tank and the engine fuel pump for fuel discharge, in addition to the traditional control logic for emergency fuel discharge volume, a mechanical structure guarantee is added, improving the reliability of stopping emergency fuel discharge. In addition, compared with the prior art of separately setting an emergency fuel discharge electric fuel pump, this application only uses an ejector pump (jet pump), a mechanical component, which will not significantly increase the on-board weight and reduce the later maintenance and operation cost of the aircraft.

[0060] Furthermore, in the Figure 1 illustrated embodiment, in the left wing fuel tank I, an emergency fuel discharge isolation valve 6 is also provided on the pipeline where the ejector pump 5 is connected to the fuel supply pump 21 or 22. When the wing fuel tank needs to discharge fuel, this isolation valve can be started to realize the supply of motive flow from the engine fuel supply pump 21 or 22 to the ejector pump 5. Similarly, in the right wing fuel tank II, an emergency fuel discharge isolation valve 6' is also provided on the pipeline where the ejector pump 5' is connected to the fuel supply pump 23 or 24. When the wing fuel tank needs to discharge fuel, this isolation valve can be started to realize the supply of motive flow from the engine fuel supply pump 23 or 24 to the ejector pump 5'.

[0061] In addition, as shown in Figure 1 again, in the left wing fuel tank I, the outlet 52 of the ejector pump 5 is connected to the emergency fuel discharge main pipeline 3 through an emergency fuel discharge branch pipeline 8, and a check valve 7 is also provided therebetween. When the emergency fuel discharge device of the wing fuel tank is not working, this check valve 7 can prevent the emergency fuel discharge volume of the central fuel tank III from entering the left wing fuel tank I through this emergency fuel discharge branch pipeline 8. Similarly, in the right wing fuel tank II, a check valve 7' is also provided between the outlet 52' of the ejector pump 5' and the emergency fuel discharge main pipeline 3. When the emergency fuel discharge device of the wing fuel tank is not working, this check valve 7' can prevent the emergency fuel discharge volume of the central fuel tank III from entering the right wing fuel tank II through this emergency fuel discharge branch pipeline 8'.

[0062] Refer to again Figure 2As shown in the figure, it is a configuration diagram of an aircraft fuel system similar to Figure 1 , which includes Figure 1 A first variant of the emergency fuel dumping system shown. Different from the Figure 1 embodiment shown: the outlet 52 of the ejector pump 5 in the left wing fuel tank I is not connected to the emergency fuel dumping main pipeline 3, but is connected to the central fuel tank III through the emergency fuel dumping branch 9, for transferring the emergency discharge fuel of the left wing fuel tank I to the central fuel tank III. Similarly, different from the Figure 1 shown, the outlet 52' of the ejector pump 5' in the right wing fuel tank III is not connected to the emergency fuel dumping main pipeline 3, but is connected to the central fuel tank III through the emergency fuel dumping branch 9', for transferring the emergency discharge fuel of the right wing fuel tank II to the central fuel tank III.

[0063] Such as the Figure 2 variant method shown can be used to avoid the problem of simultaneously considering the performance matching of fuel supply and emergency fuel dumping, flexibly adjust the problem of unbalanced fuel quantities in the left and right wing fuel tanks, and moreover, only when the emergency fuel dumping of both the wing fuel tank and the central fuel tank cannot be normally stopped, since the lowest height of the ejector pumps 5, 5' relative to the bottom of the fuel tank corresponds to the required safe fuel level, this fuel level can not only ensure that the aircraft does not overweight during safe landing but also ensure that the engine has sufficient power. According to this setting, when the fuel dumping operation cannot be stopped, when the on-board fuel quantity has dropped to the fuel tank liquid level H' as shown in Figure 3B , the suction ports 53, 53' of the ejector pumps 5, 5' are exposed above the liquid level, and the dynamic flow of the ejector pumps 5, 5' will directly flow out from the suction ports 53, 53', and the emergency fuel dumping process of the wing fuel tank will automatically be forced to stop to prevent the risk of excessive discharge of the fuel in the on-board fuel tank and the central fuel tank.

[0064] This application also provides a method for performing emergency fuel dumping using the emergency fuel dumping system of this application, and this method includes:

[0065] The supply pumps 21, 22, 23, 24 in the wing fuel tanks I, II provide dynamic flow to the ejector pumps 5, 5';

[0066] The ejector pumps 5, 5' suck the fuel in the wing fuel tanks I, II through the suction ports 53, 53', and enter the emergency fuel dumping branches 8, 8' connected to the emergency fuel dumping main pipeline 3 through the outlets 52, 52' of the ejector pumps 5, 5', or enter the emergency fuel dumping branches 9, 9' connected to the central fuel tank III.

[0067] When the fuel in the wing tanks I and II is lower than the suction inlets 53 and 53', that is, when the fuel quantity has dropped to a level that can ensure that the aircraft does not exceed the weight limit during a safe landing and can also ensure that the engine has sufficient power, the suction inlets 53 and 53' are exposed above the fuel level H'. The motive flow of the ejector pumps 5 and 5' will then discharge from the suction inlets 53 and 53'. The fuel in the wing tanks stops entering the emergency drain branch 8 and 8' of the emergency drain main pipeline or the emergency drain branch 9 and 9' connected to the central tank III, and the emergency drain stops.

[0068] The foregoing description has set forth numerous features and advantages, including various alternative modes as well as details of the structures and functions of the apparatus and / or methods. The present disclosure is intended only as illustrative and is not intended to be exhaustive. It will be apparent to those skilled in the art that various modifications can be made within the scope of the principles of the present disclosure, within the broadest scope indicated by the terms of the appended claims as expressed in their broadest sense, e.g. To the extent that these various modifications do not depart from the spirit and scope of the appended claims, these modifications are intended to be included herein.

Claims

1. An aircraft fuel emergency dumping system, the emergency dumping system is applied to a three-tank fuel system including a wing tank and a center tank, the wing tank is provided with an engine fuel supply pump to supply fuel to the aircraft engine; wherein: The emergency oil discharge system includes a central oil tank emergency oil discharge device and a wing oil tank emergency oil discharge device, the central oil tank emergency oil discharge device includes a central oil tank emergency oil discharge pump, and the central oil tank emergency oil discharge pump is connected to the emergency oil discharge main line leading to the outside of the fuselage; Features: The wing tank emergency oil discharge device includes an ejection pump and an emergency oil discharge branch, the ejection pump includes an inlet, an outlet and a suction port, wherein the inlet is connected to the engine fuel supply pump, the outlet is connected to the emergency oil discharge branch to discharge fuel from the wing tank, and the suction port is arranged to correspond to the safe oil level required for the aircraft to fly at the lowest installation height relative to the bottom of the wing tank, and the oil level can ensure that the aircraft is not overweight when landing safely and that the engine has sufficient power.

2. The aircraft fuel emergency dumping system according to claim 1, characterized in that: The emergency oil discharge branch line is connected to the emergency oil discharge main line.

3. The aircraft fuel emergency dumping system according to claim 1, characterized in that: The emergency oil release branch is connected to the central oil tank.

4. The aircraft fuel emergency dumping system according to claim 1, characterized in that: An emergency oil drain isolation valve is also provided between the ejector pump and the engine oil supply pump.

5. The aircraft fuel emergency dumping system according to claim 1, characterized in that: A one-way valve is provided on the emergency oil discharge branch line between the ejector pump and the emergency oil discharge main line.

6. The aircraft fuel emergency dumping system according to claim 1, characterized in that: The wing fuel tanks include a left wing fuel tank and a right wing fuel tank, and semi-sealed ribs are respectively provided in the left wing fuel tank and the right wing fuel tank. The semi-sealed ribs divide the left wing fuel tank into a left wing fuel collecting tank area and an outer side of the left wing fuel tank, and divide the right wing fuel tank into a right wing fuel collecting tank area and an outer side of the right wing fuel tank; the ejector pumps are respectively located in the outer side of the left wing fuel tank and the outer side of the right wing fuel tank.

7. The aircraft fuel emergency dumping system according to claim 1, characterized in that: The wing oil tanks include a left wing oil tank and a right wing oil tank, and semi-sealed ribs are respectively provided in the left wing oil tank and the right wing oil tank. The semi-sealed ribs divide the left wing oil tank into a left wing oil collecting tank area and an outer side of the left wing oil tank, and divide the right wing oil tank into a right wing oil collecting tank area and an outer side of the right wing oil tank; the ejector pumps are respectively located in the left wing oil collecting tank and the right wing oil collecting tank.

8. The aircraft fuel emergency dumping system according to claim 1, characterized in that: The emergency oil discharge main line is provided at the end of the emergency oil discharge nozzle, through which the fuel is discharged out of the fuselage.

9. A method for performing emergency fuel jettisoning using the aircraft fuel jettisoning system according to claim 1, characterized in that: The engine fuel supply pump in the wing fuel tank provides a dynamic flow to the ejector pump; The fuel in the wing oil tank is sucked by the suction port of the ejector pump and enters the emergency oil discharge branch through the outlet of the ejector pump; When the fuel in the wing tank is lower than the suction port, that is, the fuel amount has dropped to an oil level that can ensure that the aircraft does not overweight when landing safely and that the engine has sufficient power, the suction port is exposed to the oil level, the dynamic flow supplied to the ejector pump is directly discharged from the suction port, the fuel in the wing tank stops entering the emergency oil discharge branch, and the emergency oil discharge stops.

10. A method for performing emergency fuel jettisoning using the aircraft fuel jettisoning system according to claim 9, characterized in that: The fuel from the emergency oil jettisoning branch line enters the emergency oil jettisoning main line or the central fuel tank.

Images