Method for controlling a rotary-wing aircraft, corresponding system and rotary-wing aircraft

Description

[0001] The present invention relates to the field of simulations carried out on board a rotorcraft for pilot training. The present invention relates more particularly to a simulation relating to the training of a pilot in the event of a failure of one of the engines of a multi-engine rotorcraft, and in particular of a twin-engine rotorcraft.

[0002] An aircraft may include at least one rotor. The rotor(s) are rotated by a power unit. It is common for such a power unit to include at least two engines, such as turboshaft engines, piston engines or even electric motors in particular. These engines are then engaged on a power transmission chain interposed between the power unit and the rotorcraft components that consume mechanical power, including in particular the rotor(s).

[0003] Furthermore, the operation of the engines is managed by a regulation system. This regulation system makes it possible to implement an engine operating mode commonly referred to as AEO mode (from the English acronym All Engine Operative) in which all the engines in the power unit are operational and each transmits motive power to the rotorcraft's consumer components such as the rotor(s).

[0004] In order to reduce the fuel consumption of the aircraft's combustion engines, a so-called "economical" operating mode can be used, mainly during a cruising flight phase. In this economical operating mode, a single combustion engine provides the power necessary to rotate the aircraft's rotor. The other combustion engine(s) do not provide significant mechanical power, or even provide no power at all. This economical operating mode therefore induces asymmetrical operation of the combustion engines, as the combustion engines do not operate in an identical manner.

[0005] According to a first variant, a single thermal engine operates and alone ensures the rotational drive of the aircraft rotor. The other thermal engine(s) are stopped and are not supplied with fuel. In the case of a free turbine turboshaft engine, the rotating parts of the gas generator can however be kept rotating by an electric motor to facilitate and accelerate the restarting of the engine.

[0006] In a second variant, all engines are started and fueled, but only one heat engine provides significant mechanical power to rotate the aircraft's rotor(s). The other heat engine(s) are started, but operate in a so-called "super-idle" operating state and therefore provide no mechanical power.

[0007] Whatever the variant of this economical mode of operation, the operation of thermal engines is therefore asymmetrical, the thermal engines not operating in an identical way.

[0008] Thus, document EP3738888 discloses a method of operating a rotorcraft comprising a plurality of engines designed to provide motive power to at least one rotor.

[0009] Furthermore, an asymmetrical operating mode is implemented, in which at least one first motor is a so-called "active" motor, i.e. providing motive power to at least one rotor, and at least one second motor is a so-called "inactive" motor, i.e. providing substantially no motive power.

[0010] This process includes monitoring for an active engine failure. In the event of such a failure, the output power of the inactive engine is automatically increased. The reactivated inactive engine then operates in a so-called "OEI" mode (from the English acronym One Engine Inoperative). An available engine operating in OEI mode provides power for a predefined period, to temporarily allow the rotorcraft to progress in flight despite the unavailability of one of the engines.

[0011] During the transient phase from the failure of the active engine to the reactivation of the inactive engine, the mechanical power transmitted to the rotor(s) is then temporarily zero or greatly reduced and may require the pilot to perform an autorotation flight phase until the initially inactive engine has become active.

[0012] Under these conditions, it may be interesting to train pilots in such a flight sequence.

[0013] Pilot training is frequently carried out by simulation performed in real flight on board a rotorcraft, under the constraints of favorable flight conditions. To this end, a failure of one of the engines can be simulated without rendering the engines inefficient, to keep all the engines available and allow their individual operation in the event of a real failure of one of them. It is preferable, within the framework of such a simulation, to avoid individual operation of the engines according to the constraints imposed by the OEI modes. Indeed, the operation of an engine in OEI mode generates significant demands on this engine, resulting in costly maintenance operations.

[0014] This is why, in a simulation, it is common to operate all the motors simultaneously to simulate a failure of one of the motors. In the context of a simulated OEI mode execution that is the subject of training, the setpoint power to be supplied is, for example, distributed equally between all the motors kept synchronous with the power transmission chain.

[0015] In this case, each of the motors provides a mechanical power corresponding to the setpoint power divided by the number of motors. In this case, each of the motors is then in operation and in synchronous engagement on the power transmission chain. In the event of a real failure of one of the motors, the responsiveness of another motor to provide all the necessary power is satisfactory. Such simulation methods thus make it possible to preserve the motors during training in the event of a motor failure.

[0016] To appreciate the known approaches relating to various in-flight simulations of a failure of an engine of a rotorcraft equipped with several engines, one can for example refer to documents US2005234689 and US5873546. More specifically concerning the supply of a setpoint power jointly by several engines in the context of an in-flight simulation of a failure of one of the engines, one can refer to documents US4831567, US6917908, CA2452212, FR3004164, US20230019379 and US2002 / 133322.

[0017] The present invention therefore aims to propose a method for improving the training of rotorcraft pilots in the asymmetric flight phases of the power unit. Safety is thus improved during such asymmetric flight phases in the event of failure of the active engine.

[0018] Another objective of the invention is to limit damage to the engines by avoiding stressing the engines in OEI mode.

[0019] Finally, the invention allows an instructor to be able to observe the progress of a pilot's training thanks to a simulation of an asymmetrical flight phase.

[0020] The invention relates to a method for training in piloting a rotorcraft comprising at least two engines and at least one rotor participating in the lift of said rotorcraft in the air.

[0021] Such a process comprises at least the following steps: piloting the rotorcraft according to a mode called AEO in which each of said at least two engines delivers a first engine power P1 to rotate at least said at least one rotor, activating a first command to start a training phase simulating an asymmetrical flight in which a first engine of said at least two engines is configured to exclusively provide engine power to said at least one rotor and a second engine of said at least two engines is configured to provide no engine power to said at least one rotor, and deactivating the first command to exit the training phase.

[0022] According to the invention, the training phase is remarkable in that it comprises a first flight phase comprising: ∘ a first regulation with a controller regulating said at least two motors to respectively each deliver a second driving power greater than the first driving power, ∘ a first display with a display of information carrying at least two simulated powers capable of being delivered respectively by said at least two motors, each of said at least two simulated powers being distinct from the second driving power.

[0023] In other words, such a method makes it possible to simulate an asymmetrical flight phase and at least one transition phase between an asymmetrical flight and a symmetrical flight.

[0024] Indeed, the first flight phase allows each of said at least two engines to provide the second motive power to said at least one rotor but a display makes it possible to simulate to at least one pilot that the first engine exclusively provides motive power to said at least one rotor.

[0025] Such a display may, for example, comprise a screen enabling the display of dials each with a movable needle or scales each with a movable index forming the information carrying the at least two simulated powers.

[0026] The controller may comprise, for example, at least one processor and at least one memory, at least one integrated circuit, at least one programmable system, at least one logic circuit, these examples not limiting the scope given to the expression "controller". The term processor may also designate a central processing unit known by the acronym CPU, a graphics processing unit GPU, a digital unit known by the acronym DSP, a microcontroller, etc.

[0027] Optionally, the training phase can be triggered by a pilot when rotorcraft conditions are compatible with asymmetric flight.

[0028] Therefore, such a first phase of flight can be implemented as long as the conditions of this first phase of flight remain compatible with asymmetric flight.

[0029] Thus, the transition between an asymmetrical flight and a symmetrical flight can be implemented automatically by the method when the conditions of the rotorcraft change, such as for example when the height of the rotorcraft relative to the ground decreases below a threshold value, when the forward speed of the rotorcraft is below a threshold value or when an instantaneous power demand exceeds a threshold value.

[0030] Furthermore, a rotorcraft conditions display can indicate to the pilot whether the initial conditions when piloting the rotorcraft in AEO mode are compatible with asymmetric flight.

[0031] In this case, the first command can be activated by the pilot to start an asymmetric flight training phase.

[0032] Otherwise, the first command may be inhibited.

[0033] Once the pilot has completed training in asymmetric flight and / or transition phases, the pilot then deactivates the first control to exit the training phase.

[0034] Advantageously, said at least two simulated powers may comprise a first simulated power and a second simulated power, the first simulated power being displayed as exclusively supplied by the first engine, the first simulated power being greater than the second engine power during the first flight phase, the second simulated power being displayed as exclusively supplied by the second engine, the second simulated power being zero during the first flight phase.

[0035] In practice, when said at least two simulated powers comprise a first simulated power and a second simulated power, after the first flight phase, the method may comprise an activation of a second command to start a second flight phase making it possible to implement training piloting of the rotorcraft in autorotation, the second flight phase comprising: a second regulation with the controller regulating said at least two motors, the second regulation successively implementing: ∘ a reduction in the driving power supplied respectively by each of said at least two motors from the second driving power to a minimum threshold value lower than the first driving power, ∘ a maintenance of the driving power supplied respectively by each of said at least two motors at the minimum threshold value, and ∘ an increase in the driving power supplied respectively by each of said at least two motors up to a maximum threshold value greater than or equal to the first driving power, a second display with the display of a reduction in a first current value of the first simulated power simulating a failure of the first motor then an increase in a second current value of the second simulated power simulating a start of the second motor.

[0036] Consequently, such a method can also make it possible to simulate a failure of the active engine during a simulated asymmetric flight and to train a pilot to perform an autorotation phase during which a start of the second engine is then simulated. Furthermore, such a second asymmetric flight phase can be relatively long and last 10 to 15 seconds, or even up to 20 seconds.

[0037] Such a simulation is obtained by regulating with the controller the driving power actually transmitted jointly by the at least two motors.

[0038] Thus, during this second phase of flight, the method makes it possible to simulate a sudden drop in the driving power transmitted to said at least one rotor by the first engine, an absence of driving power transmitted to said at least one rotor and then a progressive increase in the driving power transmitted to said at least one rotor by the second engine.

[0039] Furthermore, the decrease in the driving power supplied respectively by each of said at least two motors may have a predetermined negative rate of variation.

[0040] Maintaining the driving power supplied respectively by each of said at least two motors at the minimum threshold value Pmin can be achieved for a predetermined duration by means of a stopwatch.

[0041] The increase in the driving power provided respectively by each of said at least two motors may have a predetermined positive rate of variation.

[0042] Advantageously, after the second flight phase, the method may include a third flight phase comprising: ∘ a third regulation with the controller regulating said at least two motors to respectively each deliver the maximum threshold value Pmax, and ∘ a third display with said display of the first simulated power as being zero, and of the second simulated power as being greater than the second motor power.

[0043] In other words, the third flight phase can be used to simulate operation of the second engine in OEI mode, the set engine power to be supplied to the rotor(s) then being equally distributed between all the engines kept synchronous with the power transmission chain.

[0044] The training method according to the invention then makes it possible to train a pilot to subsequently perform a first transition between the AEO mode of the engines and an asymmetrical mode, then a second transition between this asymmetrical mode and the OEI mode of the second engine.

[0045] Furthermore, the first command and the second command can be implemented in different ways.

[0046] According to a first exemplary embodiment, the first control and the second control can be activated and deactivated by a single control member.

[0047] For example, such a control organ can be formed by a switch or rotary knob.

[0048] According to a second exemplary embodiment, the first control can be activated and deactivated by a first control member, the second control can be activated and deactivated by a second control member separate from the first control member.

[0049] In this case, the first control member and the second control member are, for example, bistable buttons which can be operated one after the other.

[0050] According to a third exemplary embodiment, the first command can be activated by a first control member, the second command can be activated by a second control member separate from the first control member, the first command and the second command can be deactivated by a third control member separate from the first control member and second control member.

[0051] In this case, the first control member and the second control member are, for example, monostable buttons arranged on a dashboard or on a control lever of the rotorcraft.

[0052] The third control organ is for example formed by a monostable switch of the button or trigger type arranged on a control lever of the rotorcraft.

[0053] Furthermore, the regulation of the driving power transmitted jointly by the at least two motors can be implemented in different ways.

[0054] According to a first variant, the controller can regulate a motor torque transmitted by each of said at least two motors to a power transmission chain allowing transmission of motor power to said at least one rotor.

[0055] In this case, the controller makes it possible to make the power transmitted to said at least one rotor negligible, while ensuring minimal power in order to maintain synchronization of the two motors with the power transmission chain which may include a freewheel.

[0056] Desynchronization between a driving part and a driven part of this freewheel can be avoided by controlling the engine torque to a minimum value close to zero. This control of the transmitted engine torque can be achieved via a dedicated control loop allowing, initially, to reduce the engine torque of each engine to a low value, in order to decelerate the engines very quickly. When this target value is reached, the deceleration is stopped and the minimum torque value is actively controlled by the torque loop, in order to maintain the minimum torque level during a phase without engine power transmitted to the rotor(s) corresponding to a part of the second simulated asymmetric flight phase.

[0057] According to a second variant, the controller can regulate a rotation speed of at least two respective gas generators of each of said at least two motors. In this case, the controller makes it possible to adjust the rotation speed of each gas generator to a target level in order to decelerate the motors very quickly and obtain a phase without driving power transmitted to the rotor(s).

[0058] Such a target rotation speed of the engine gas generators can be determined by flight tests, bench tests or even by simulations.

[0059] Depending on this target rotation speed of the gas generators, the at least two engines will then be able to deliver a driving power to said at least one main rotor equal to the threshold power during part of the second simulated asymmetric flight phase.

[0060] According to a third variant, the controller can regulate a rotational speed of at least two input shafts of a main power transmission box, each of said at least two input shafts being respectively rotated by said at least two motors.

[0061] In this case, the controller allows to adjust the rotation speed of each input shaft to a target level in order to decelerate the motors very quickly and obtain a phase without driving power transmitted to the rotor(s).

[0062] As with the gas generator, such a target rotational speed of the input shafts of the main power transmission box can be determined by flight tests, bench tests or even by simulations.

[0063] Depending on this target rotation speed of the input shafts of the main power transmission box, the at least two engines will then be able to deliver a driving power to said at least one main rotor equal to the threshold power during part of the second simulated asymmetric flight phase.

[0064] The present invention also relates to a computer program comprising instructions which, when the program is executed, lead to implementing the pilot training method according to the invention described above.

[0065] The program is for example executed by a computer or a calculator, comprising at least one processor, at least one integrated circuit, at least one programmable system, at least one logic circuit, and a memory, these examples not limiting the scope given to the expression “computer” or “calculator”.

[0066] The memory is used to store the computer program as well as various information used by the computer program, namely the engine power data to be transmitted to said at least one rotor depending on the different flight phases, condition models compatible with asymmetric flight, meteorological data and environmental data.

[0067] The present invention also relates to a system for training in piloting a rotorcraft comprising at least two engines and at least one rotor participating in the lift of the rotorcraft in the air.

[0068] Furthermore, such a system is remarkable in that it is configured to implement the pilot training method according to the invention previously described, the system comprising the controller and the display.

[0069] Such a system is then integrated into a rotorcraft and as such constitutes equipment of the rotorcraft. The pilot training system can then be connected to a flight management device of the rotorcraft or to an automatic piloting device of the rotorcraft. In addition, the simulation of the engine power transmitted to said at least one main rotor can be displayed on a display such as a screen of the rotorcraft, glasses or even on a visor of a helmet worn by a pilot.

[0070] The present invention finally aims at a rotorcraft remarkable in that it comprises a pilot training system according to the invention previously described.

[0071] The invention and its advantages will appear in more detail in the context of the description which follows with examples given for illustrative purposes with reference to the appended figures which represent: there figure 1 , a diagram of a rotorcraft according to the invention, the figure 2 , a flowchart illustrating a first example of a training method in accordance with the invention, the figure 3 , a flowchart illustrating a second example of a training method in accordance with the invention, the figure 4 , a graph illustrating the powers provided by the at least two engines and simulated, in accordance with the invention figure 5 , an exemplary embodiment of a control member allowing the implementation of the method, in accordance with the invention, the figure 6 , an example of embodiment of two control members allowing the implementation of the method, in accordance with the invention, and the figure 7 , an example of embodiment of three control members allowing the implementation of the method, in accordance with the invention.

[0072] Elements present in several distinct figures are assigned a single reference.

[0073] As represented in the figure 1 , the invention relates to a rotorcraft 1 comprising at least one lifting rotor 5 driven in rotation by at least two engines 3, 4 such as turboshaft engines each comprising a gas generator 70, 71 and at least one free power turbine respectively downstream of a gas generator. Each free power turbine is secured to a power shaft capable of being connected to a power transmission chain 8. Furthermore, such a power transmission chain 8 allows transmission of driving power from the engines 3, 4 to the rotor 5. This power transmission chain 8 may in particular comprise a main power transmission box 80 and two input shafts 81, 82 cooperating with the main power transmission box 80.

[0074] Furthermore, the rotorcraft 1 is equipped with a pilot training system 2. Such a system 2 comprises in particular a controller 6 regulating said at least two engines 3, 4 and a display 7 for displaying powers supplied respectively by said at least two engines 3, 4 or for displaying simulated powers capable of being supplied by said at least two engines 3, 4.

[0075] The controller 6 may comprise engine computers, or even a central computer controlling the engine computers. Such a controller also comprises sensors and at least one fuel metering device for regulating said at least two engines 3, 4.

[0076] Furthermore, the regulation of the at least two motors 3, 4 can be implemented in different ways.

[0077] Thus, according to a first exemplary embodiment, the controller 6 can regulate a motor torque transmitted by each of said at least two motors 3, 4 to the power transmission chain 8. In this case, the controller 6 then comprises torque sensors such as torque meters measuring the motor torque transmitted by each of said at least two motors 3, 4 to the power transmission chain 8.

[0078] According to a second exemplary embodiment, the controller 6 can regulate a rotation speed of the at least two gas generators 70, 71 respective to each of said at least two engines 3, 4. In this case, the controller 6 then comprises speed sensors measuring the rotation speed of each of said at least two gas generators 70, 71.

[0079] According to a third exemplary embodiment, the controller 6 can regulate a rotation speed of the at least two input shafts 81, 82 of the main power transmission box 80. In this case, the controller 6 then comprises speed sensors measuring the rotation speed of each of the at least two input shafts 81, 82.

[0080] Further, as represented in the figure 2 , the invention also relates to a method 10 comprising piloting 11 of the rotorcraft 1 according to an AEO mode in which each of said at least two engines 3, 4 delivers a first motive power P1 to drive in rotation at least said at least one rotor 5. Thus, the controller 6 regulates the fuel supply according to a setpoint allowing each of said at least two engines 3, 4 to deliver the first motive power P1.

[0081] Such a method 10 then comprises an activation 12 of a first command to start a training phase E simulating an asymmetrical flight in which a first engine 3 of said at least two engines 3, 4 is configured to provide exclusively motive power to said at least one rotor 5 and a second engine 4 of said at least two engines 3, 4 is configured to provide no motive power to said at least one rotor 5.

[0082] The first command thus transmits an analog, digital or optical signal to the controller 6 which in response carries out a first regulation 13. This training phase E therefore comprises a first flight phase V1 comprising the first regulation 13 with the controller 6 regulating said at least two motors 3, 4 to respectively each deliver a second driving power P2 greater than or equal to the first driving power P1.

[0083] Such a first regulation 13 may for example consist of adapting a fuel flow rate by means of a fuel metering device upstream of a combustion chamber of each engine 3, 4.

[0084] Likewise, the first command transmits an analog, digital or optical signal to the display 7 which in response produces a first display 14. The first flight phase V1 comprises this first display 14 with the display 7 of information carrying at least two simulated powers PS1, PS2 capable of being delivered respectively by said at least two engines 3, 4, each of said at least two simulated powers PS1, PS2 being distinct from the second engine power P2.

[0085] Furthermore, said at least two simulated powers PS1, PS2 comprise a first simulated power PS1 and a second simulated power PS2.

[0086] The first simulated power PS1 is displayed on the display 7 as being exclusively supplied by the first motor 3, for example via a needle arranged opposite a dial.

[0087] As shown on the figure 4 , this first simulated power PS1 is then greater than the second engine power P2 during this first flight phase V1. Typically when the rotorcraft is equipped with two engines, the first simulated power PS1 can be chosen equal to twice the second engine power P2.

[0088] The second simulated power PS2 is displayed as being exclusively supplied by the second engine 4, this second simulated power PS2 being zero during said first flight phase V1.

[0089] The method 10 then comprises a deactivation 15 of the first command to exit the training phase E.

[0090] Such deactivation 15 can be implemented automatically by the flight training system 2 if it includes environmental sensors measuring the flight conditions of the rotorcraft and when these flight conditions become incompatible with asymmetric flight.

[0091] Alternatively or additionally, deactivation 15 may also be operated by a control member actuated by a rotorcraft pilot when asymmetric flight training is complete or in an emergency.

[0092] Process 20 of the figure 3 may also include the steps of piloting 21 the rotorcraft 1 according to an AEO mode, activation 22 of a first command then the steps of regulation 23 and display 24 as previously described in figure 2 for process 10.

[0093] In addition to these steps, the method 20 then comprises, after the first flight phase V1, an activation 25 of a second command to start a second flight phase V2 making it possible to implement training piloting of the rotorcraft 1 in autorotation.

[0094] Like the first flight phase V1, the second command thus transmits an analog, digital or optical signal to the controller 6 which in reaction carries out a second regulation 26 regulating said at least two motors 3, 4.

[0095] The second flight phase V2 therefore implements this second regulation 26 with controller 6.

[0096] During such a second regulation 26, the controller 6 regulates each motor to successively implement a reduction 261 of the driving power supplied respectively by each of said at least two motors 3, 4 from the second driving power P2 to a minimum threshold value Pmin lower than the first driving power P1, a maintenance 262 of said driving power supplied respectively by each of said at least two motors 3, 4 at the minimum threshold value Pmin, then an increase 263 of the driving power supplied respectively by each of said at least two motors 3, 4 up to a maximum threshold value Pmax greater than or equal to the first driving power P1.

[0097] The second flight phase V2 also includes a second display 27 with the display 7 of a decrease in a first current value of the first simulated power PS1 simulating a failure of the first engine 3 then an increase in a second current value of the second simulated power PS2 simulating a start of the second engine 4.

[0098] Furthermore, after the second flight phase V2, the method 20 may optionally comprise a third flight phase V3 comprising a third regulation 28 with the controller 6 which regulates said at least two motors 3, 4 so that each motor delivers a power equal to the maximum threshold value Pmax, and a third display 29 with the display 7 of the first simulated power PS1 as being zero, and of said second simulated power PS2 as being equal to twice the second motor power P2.

[0099] Finally, the method 20 includes a deactivation 35 of the first command to exit the training phase E.

[0100] As for deactivation 15, such deactivation 35 can be implemented automatically by the system 2 and alternatively or additionally, it can also be operated by a control member actuated by a pilot of the rotorcraft.

[0101] As represented in the figure 5 , the first control and said second control can be activated and deactivated by a single control member 40 represented in the form of a rotary switch with at least three stable positions arranged on a dashboard 45.

[0102] A first position may correspond to the deactivation of the first command, a second position may correspond to the activation of the first command and the deactivation of the second command and a third position may correspond to the activation of the first command and the activation of the second command.

[0103] According to another example illustrated in the figure 6 , the first control can be activated and deactivated by a first control member 50, the second control can be activated and deactivated by a second control member 51 separate from the first control member 50.

[0104] The first control member 50 and the second control member 51 can then be formed by bistable switches.

[0105] A first position of the first control member 50 relative to a dashboard 55 may correspond to the deactivation of the first control and a second position of the first control member 50 may correspond to the activation of the first control.

[0106] Likewise, a first position of the second control member 51 relative to a dashboard 55 may correspond to the deactivation of the second control and a second position of the second control member 51 may correspond to the activation of the second control.

[0107] Finally, according to another example illustrated in the figure 7 , the first control can be activated by a first control member 60 movable relative to a control lever 65, the second control can be activated by a second control member 61 separate from the first control member 60.

[0108] Furthermore, the first control and the second control can be deactivated by a third control member 62 movable relative to the control lever 65. Such a third control member 62 can be formed by a trigger and is distinct from the first control member 60 and second control member 61.

[0109] Naturally, the present invention is subject to numerous variations in its implementation. Although several embodiments have been described, it is understood that it is not conceivable to exhaustively identify all possible embodiments. The invention is defined in the claims.

Claims

1. Method (10, 20) for training the piloting of a rotorcraft (1) comprising at least two engines (3, 4) and at least one rotor (5) contributing to helping keep said rotorcraft (1) in the air, said method (10, 20) comprising at least the following steps: - piloting (11, 21) said rotorcraft (1) according to a mode (AEO) in which each of said at least two engines (3, 4) delivers a first engine power (P1) to rotate at least said at least one rotor (5), - activating (12, 22) a first command to start a training phase (E) simulating an asymmetric flight in which a first engine (3) of said at least two engines (3, 4) is configured to supply an engine power exclusively to said at least one rotor (5) and a second engine (4) of said at least two engines (3, 4) is configured to supply no engine power to said at least one rotor (5), - deactivating (15, 35) said first command to leave said training phase (E), characterised in that said training phase (E) comprises a first flight phase (V1) comprising: ∘ a first regulation (13, 23) with a controller (6) regulating said at least two engines (3, 4) each to deliver respectively a second engine power (P2) greater than said first engine power (P1), ∘ a first display (14, 24) with a display unit (7) of an item of carrier information of at least two simulated powers (PS1, PS2) capable of being delivered respectively by said at least two engines (3, 4), each of said at least two simulated powers (PS1, PS2) being distinct from said second engine power (P2).

2. Method according to claim 1, characterised in that said at least two simulated powers (PS1, PS2) comprise a first simulated power (PS1) and a second simulated power (PS2), said first simulated power (PS1) being displayed as exclusively supplied by said first engine (3), said first simulated power (PS1) being greater than said second engine power (P2) during said flight phase (V1), said second simulated power (PS2) being displayed as exclusively supplied by said second engine (4), said second simulated power (PS2) being zero during said first flight phase (V1).

3. Method according to any one of claims 1 or 2, characterised in that, when said at least two simulated powers (PS1, PS2) comprise a first simulated power (PS1) and a second simulated power (PS2), after said first flight phase (V1), said method (20) comprises an activation (25) of a second command to start a second flight phase (V2) making it possible to implement a training of piloting of said rotorcraft (1) in autorotation, said second flight phase (V2) comprising: - a second regulation (26) with said controller (6) regulating said at least two engines (3, 4), said second regulation (26) implementing successively: ∘ a decrease (261) in said engine power supplied respectively by each of said at least two engines (3, 4) of said second engine power (P2) to a minimum threshold value (Pmin) less than said first engine power (P1), ∘ a maintenance (262) of said engine power supplied respectively by each of said at least two engines (3, 4) at said minimum threshold value (Pmin), and ∘ an increase (263) in said engine power supplied respectively by each of said at least two engines (3, 4) up to a maximum threshold value (Pmax) greater than or equal to said first engine power (P1), - a second display (27) with said display unit (7) of a decrease in a first current value of said first simulated power (PS1) simulating a failure of said first engine (3) then an increase of a second current value of said second simulated power (PS2) simulating a starting of said second engine (4).

4. Method according to claim 3, characterised in that, after said second flight phase (V2), said method (20) comprises a third flight phase (V3) comprising: ∘ a third regulation (28) with said controller (6) regulating said at least two engines (3, 4) to each deliver respectively said maximum threshold value (Pmax), and ∘ a third display (29) with said display unit (7) of said first simulated power (PS1) as zero, and of said second simulated power (PS2) as being greater than said second engine power (P2).

5. Method according to any one of claims 3 to 4, characterised in that said first command and said second command are activated and deactivated by one single command member (40).

6. Method according to any one of claims 3 to 4, characterised in that said first command is activated and deactivated by a first command member (50), said second command is activated and deactivated by a second command member (51) distinct from said first command member (50).

7. Method according to any one of claims 3 to 4, characterised in that said first command is activated by a first command member (60), said second command is activated by a second command member (61) distinct from said first command member (60), said first command and said second command are deactivated by a third command member (62) distinct from said first command member (60) and second command member (61).

8. Method according to any one of claims 1 to 7, characterised in that said controller (6) regulates an engine torque transmitted by each of said at least two engines (3, 4) to a power transmission chain (8) enabling an engine power transmission to said at least one rotor (5).

9. Method according to any one of claims 1 to 7, characterised in that said controller (6) regulates a rotation speed of at least two respective gas generators (70, 71) of each of said at least two engines (3, 4).

10. Method according to any one of claims 1 to 7, characterised in that said controller (6) regulates a rotation speed of at least two drive shafts (81, 82) of a main power transmission box (80), each of said at least two drive shafts (81, 82) being respectively rotated by said at least two engines (3, 4).

11. Computer program comprising instructions which, when said program is executed, lead to implementing the method (10, 20) for training the piloting according to any one of claims 1 to 10.

12. System (2) for training the piloting of a rotorcraft (1) comprising at least two engines (3, 4) and at least one rotor (5) contributing to a sustentation of said rotorcraft in the air, characterised in that said system (2) is configured to implement the method (10, 20) for training the piloting according to any one of claims 1 to 10, said system (2) comprising said controller (6) and said display unit (7).

13. Rotorcraft (1), characterised in that said rotorcraft (1) comprises a training system (2) according to claim 12.