System for simulating a multi-engine aircraft

Abstract

The invention relates to a system for adapting a single-engine aircraft to simulate the behavior of a multi-engine aircraft, particularly for instruction and training purposes. Figure 1

Description

Title of the invention: System for the simulation of a multi-engine aircraft technical field

[0001] The invention belongs to the field of electric flight controls and aircraft equipped with such controls. Previous technique

[0002] Electric flight controls allow the aerodynamic surfaces and engines of an aircraft to be piloted according to the actions of the pilot on the piloting instruments: throttles, stick, rudder pedals, without direct mechanical link, such as cables, between these control instruments and the piloted means.

[0003] The pilot's action on a control element is measured, for example by means of a position sensor, this measurement is interpreted by a computer, which transcribes this action into movement orders for actuators acting on the aerodynamic surfaces or the propulsion means according to a control law.

[0004] This control law aims to optimize the operation of the aircraft and its safety by keeping it within its flight envelope.

[0005] Depending on the aircraft, several control laws can be used and selected, for example according to the phase of flight, so that the same action on one or more control elements can result in different movements of the actuators taken individually or in combination.

[0006] Thus, the choice of a control law makes it possible to completely modify the behavior of an aircraft in response to a control instruction entered by the pilot via the piloting instruments.

[0007] Even if a fundamental modification of the apparent behavior of the aircraft, that is to say as seen by the pilot acting on the control organs, is not the objective of the electrical controls, there are examples which may go in this direction.

[0008] For example, document WO 2021 / 224490 Al describes a multi-propeller aircraft comprising a plurality of electric motors on each wing, whose control organs are those of a single-engine aircraft, with a single throttle lever, and whose computers associated with the electric controls reproduce the behavior of a single-engine aircraft.

[0009] Document WO 2008 / 097319 A2 describes an aircraft equipped with electrical controls whose computer can generate a plurality of simulated pilot control signals from at least one aircraft maneuver control without direct intervention from the pilot.

[0010] The training and qualification of pilots on multi-engine aircraft is expensive because these aircraft have high operating and maintenance costs.

[0011] These training exercises include, in particular, learning the reactions and protocols in case of a failure causing asymmetrical behavior, more specifically the failure of an engine.

[0012] These malfunctions mainly result in yaw and roll responses of the aircraft, the combination of which can lead to disturbing behavior for the pilot, potentially leading to loss of control of the aircraft.

[0013] To date, to expose trainee pilots to this type of unusual behavior, the solution is either the simulator or the use of a twin-engine aircraft placed in these asymmetric conditions; the latter solution presents a high cost and a high carbon footprint, the operation of a twin-engine aircraft being 2 to 3 times more expensive and having a carbon footprint than a single-engine aircraft.

[0014] Moreover, the generation of an asymmetric situation, for example by voluntarily stopping one of the engines of a twin-engine aircraft presents risks, even in the presence of an instructor, as the aircraft may become unstable and irrecoverable in the event of inappropriate maneuvers by the student pilot. Summary of the invention

[0015] These disadvantages of the prior art can be resolved by a system comprising:

[0016] an aircraft comprising an onboard cockpit including control elements and piloting instruments, a main propulsion system and electrical controls configured to move at least one aerodynamic surface and modify at least one parameter of the main propulsion system as a function of an action on at least one control element;

[0017] a sensor configured to measure the action on at least one control element;

[0018] a computer comprising an input port configured to receive a signal from the sensor, an output port configured to send an aerodynamic setpoint signal to an actuator configured to move at least one aerodynamic surface and an engine setpoint signal to modify at least one parameter of the main thruster, a non-volatile memory comprising a control law and a computer program configured to calculate the aerodynamic setpoint and the engine setpoint as a function of the signal from the sensor and the control law;

[0019] wherein the control law and the computer program are configured to reproduce the behavior of a simulated aircraft comprising more than one main propulsion system.

[0020] Thus, the use of a particular control law for piloting the main propulsion means and the aerodynamic surfaces according to the pilot's actions on the control elements, makes it possible to give the aircraft of the system, for example a single-engine aircraft, a behavior similar to that of a multi-engine aircraft, and in particular to simulate an asymmetry in the propulsion.

[0021] The system can be implemented according to the embodiments set out below, which are to be considered individually or according to any technically operative combination.

[0022] According to one embodiment, the aircraft is fixed-wing and at least one aerodynamic surface includes a rudder and at least one aileron on each wing.

[0023] According to one embodiment, the aircraft is a single-engine aircraft and the simulated aircraft is a twin-engine aircraft, the control organs include a thrust control comprising two levers independent of each other, in which an aerodynamic setpoint signal and an engine setpoint signal are generated as a function of an average angular position and an angular position difference between the two independent levers.

[0024] The two independent thrust control levers can act on a main thruster power control via a differential gear train configured to move the main thruster power control according to the average angular position and the difference in angular position between the two independent levers.

[0025] The difference in position of the two independent levers of the thrust control can produce an aerodynamic setpoint.

[0026] Thus the possible asymmetry of the behavior of the simulated aircraft is produced by a configuration of the aerodynamic surfaces.

[0027] The piloting instruments are displayed on at least one computer screen and the display includes a simulated display of conditions of two engines, such as: torque, engine and propeller rotation speeds, temperature, in particular as a function of the average angular position and the difference in angular position between the two independent levers.

[0028] The control devices may include an instructor control to trigger a behavior of the simulated aircraft subjected to an engine failure.

[0029] The control organs include a reset control configured to exit a simulated aircraft mode.

[0030] According to one embodiment, the aircraft includes an auxiliary electric thruster on each wing, the computer and the control law being configured to calculate at least one parameter relating to each auxiliary electric thruster.

[0031] The main propulsion system can be a turboprop. Brief description of the drawings

[0032] The system is implemented according to the non-limiting embodiments set out below with reference to [Fig. 1] to [Fig. 4] in which: Fig. 1

[0033] [Fig.l] represents in top view an example of an aircraft embodiment for the implementation of the system; Fig. 2

[0034] [Fig.2] is a schematic perspective view of an example embodiment of a cockpit; Fig.3

[0035] [Fig.3] is an example of a kinematic diagram of a thrust control; Fig. 4

[0036] [Fig.4] and a simplified functional diagram of an electrical control device primary and secondary, Description of the implementation methods

[0037] [Fig.1] According to one embodiment, the system comprises a single-engine fixed-wing aircraft (100), including a main propulsion unit (110) which may be a turboprop.

[0038] The aircraft may be an existing single-engine aircraft with or without electric primary controls, which may receive specific modifications to enable it to better perform asymmetric behavior.

[0039] By way of example, these arrangements may include aerodynamic surfaces such as ailerons (121, 122) on each of the wings to introduce roll effects and a rudder (130) to introduce yaw effects.

[0040] The ailerons and rudder can be those of the existing aircraft when it is equipped with electrical controls, they can also be aerodynamic extensions linked to existing surfaces to increase their effects, or, in particular when the aircraft is not electrically controlled, they can be added aerodynamic surfaces with electrical control.

[0041] Alternatively or in a complementary manner, auxiliary electric thrusters (151, 152) can be installed for example at the wingtip.

[0042] [Fig.2] The cockpit (200) comprises a pilot's seat (201) and a seat instructor (202). Each of these positions includes the display of flight parameters in the form of computer screens (241, 242).

[0043] The control devices include, for each seat, a joystick (221, 222) and a rudder pedal (not shown), and a central thrust control (210) comprising two independent levers (211, 212).

[0044] All these controls include one or more sensors of their position, for example in the form of one or more incremental encoders, this position information of the control elements is interpreted by a computer and translated into movement orders of the aerodynamic surfaces, either existing aerodynamic surfaces or additional aerodynamic surfaces referred to electrically controlled according to the embodiment, according to a control law, in an electrical control device also called "Fly By Wire".

[0045] The parameters of the main motor are determined according to a function of the relative position of the two levers, comprising by an average angular position and a difference in angular position.

[0046] According to exemplary embodiments, this control of the main thruster can be purely electrical, for example, based on information delivered by one or more encoders measuring the position of each independent lever, then performing a mathematical processing of this information, or, according to another exemplary embodiment, the control of the main thruster is, at least in part, based on a mechanical device using, for example, a differential gear train as described later, which acts on an existing control in place of the single-lever control of the main thruster, or even, by a combination of these embodiments.

[0047] Thus, by maneuvering the thrust control (210) with two independent levers, the student pilot reproduces thrust and drag effects similar to those of a twin-engine aircraft.

[0048] The cockpit is on board, that is to say that the pilot and the instructor actually fly in the aircraft whose behavior is simulated, the piloted aerodynamic surfaces are subjected to an aerodynamic flow and produce lift and drag, the electrical controls modify the conditions of real flight: it is not a ground flight simulator.

[0049] [Fig.3] according to an example embodiment the thrust control (210) comprising The two independent levers (211, 212) are interfaced with the main motor's power control. In this embodiment, this interface is achieved via a differential epicyclic gear train producing a control or sensor displacement (310, 320) as a function of the relative position and movement of the two independent levers.

[0050] Thus, the two independent levers (211, 212) can be moved angularly around an axis (330) independently of each other as seen from the cockpit, but the effect of their relative displacement on the sensors (310, 320) or directly on the control of the main thruster, are dependent on the characteristics of the differential gear.

[0051] By way of non-imitative example, a sensor (310) is an incremental encoder which delivers information (319) proportional to the angular displacement of the axis (315) of the main thruster power control.

[0052] This information (319) is directed to a computer in the engine's electrical control system, commonly referred to as "FADEC" for "Full Authority Digital Engine Control." Such a system manages several propeller parameters, such as engine speed, propeller pitch, etc. Such a device is known from the prior art and is not described further.

[0053] Thus, the system uses the power control of the single-engine main thruster while the thrust control comprises two apparently independent levers (211, 212).

[0054] According to this embodiment, when the two independent levers are moved together, two planetary gears (331, 332) rotate together and drive a planet carrier (340) around a rotation axis (330) of the planetary gears. The rotation of the planet carrier is transmitted via a gear train (341, 342) to the power drive shaft (315) of the main thruster.

[0055] Thus, the angular position of the satellite carrier (340) is proportional to an average angular position of the two independent levers.

[0056] If one of the independent levers is moved independently of the other, for example the right lever (212) is moved while the left lever remains fixed, then the right planetary gear (332) rotates through an angle equivalent to that of the right lever (212). The left planetary gear (331) remains fixed, the satellite (345) rotates through an angle dependent on the gear ratio between the planetary gear and the satellite, and drives the satellite carrier (340). This movement is transmitted via a pair of gears (341, 342) to the position sensor (310) of the shaft (315) of the main thruster's power control.

[0057] Thus, assuming that the respective numbers of teeth Z are such that:

[0058] Z332 = Z331 = 2.Z 345

[0059] Z341 = Z342

[0060] So for an angular displacement ô of one of the two levers relative to the other the angular displacement of the axis (315) of the main thruster power control is ô / 2.

[0061] On the other hand, if the two independent levers (211, 212) are moved together by an angle a, then the angular displacement of the axis (315) of the main thruster power control is equal to a.

[0062] When the two independent levers are moved together, the rotation of the satellite (345) is zero.

[0063] Thus, the information communicated by the gear train to the main engine's throttle control is a function of an average angular position and a difference in angular position between the two independent levers. The power demanded from the main engine via this mechanism corresponds to the sum of the powers that would be demanded from two engines, given the position of two levers on a twin-engine aircraft.

[0064] When one of the two independent levers (211, 212) is moved relative to the other, the rotation of the satellite (345) causes the rotation of an asymmetry control shaft (325) as a function of the tooth ratio of an asymmetry gear pair (321, 322) and consequently of the asymmetry sensor (320), which generates a signal (329) which is interpreted by a computer to modify the position of the aircraft's aerodynamic surfaces so as to reflect a corresponding asymmetric behavior.

[0065] Thus, if the right lever (212) is pushed fully forward and the left lever (211) is pulled fully back, then the position of the sensor (310) on the axis (315) of the main thruster power control is at mid-travel, and the information (319) leads to the main thruster operating at half power. The position of the asymmetry control axis (325) is such that the signal (329) leads to rudder and aileron commands such that the aircraft yaws to the left and rolls by raising the right wing.

[0066] The combination of the main engine power control and the aerodynamic surfaces by the differential associated with the thrust control (210) makes it possible to achieve a simulated twin-engine aircraft behavior.

[0067] The thrust control may include a locking device for the two independent levers, which, when engaged, prevents any relative movement of one lever with respect to the other. Under these conditions, the thrust control acts on the axis (315) of the main propulsion power control like the single throttle of a single-engine control.

[0068] Returning to [Fig.2], the instructor can select different modes for the display of the engine gauges (215): either a single-engine display, with one gauge per parameter corresponding to the actual operating parameters of the main thruster, or a simulated twin-engine display with a pair of gauges for each engine parameter depending in particular on the engine signal (319) from the thrust control (210).

[0069] An instructor control (290) for simulating engine failure allows this type of behavior to be triggered. By activating this instructor control (290) the main propulsion power is reduced by half and the aerodynamic surface controls are adjusted to reproduce the effect of such a failure on the yaw and roll of the aircraft.

[0070] The computer may include safeguards so that the triggering of such a virtual failure, but with real effects, or an inappropriate action by the student pilot in the face of this situation are recorded, for example for the purpose of reporting on a training session, but do not lead to excessively unstable aircraft behavior.

[0071] Similarly, a reset command (291) can allow the instructor to exit the simulated behavior mode and return to symmetrical, single-engine behavior.

[0072] [Fig.4] According to one embodiment, the system may include a device of primary electrical controls (400) including a first computer (410) relating to the engine parameters of the main thruster, including a non-volatile memory (411) including a control law and a computer program to generate, for example, a rotation speed setpoint (412) and a propeller pitch setpoint (413) as a function of at least one signal (419) from a power control sensor of the main thruster.

[0073] The primary electrical control device may include a second computer (420) comprising a non-volatile memory (421) comprising a control law and a computer program relating to the control of the aerodynamic surfaces as a function of the signals emitted by the stick (421, 422) and rudder (423) sensors.

[0074] Thus this second computer sends, for example, a right position command (425) to an actuator configured to move the right wing, a left position command (426) to an actuator configured to move the left wing and a rudder position command (430) to an actuator configured to move the rudder.

[0075] As previously stated, it is not necessary for the primary controls, in single-engine mode, to be electric; they can be of any kind: for example, by cables or hydraulics, provided that the aerodynamic surfaces configured to generate an asymmetry are electrically controlled.

[0076] In simulated aircraft mode, a secondary electrical control computer (430) includes a third non-volatile memory (431) comprising a control law and a computer program which modifies the instructions (412, 413, 425, 426, 430) from the primary controls according to the signals (319, 329) from the thrust control encoders so as to produce an asymmetry of behavior.

[0077] A person skilled in the art understands that the implementation method is described by considering multiple computers but that the same result can be achieved with a single computer containing in memory instructions performing the same functions.

[0078] Returning to [Fig.1], according to one embodiment, the system includes auxiliary electric thrusters fixed, for example, to the ends of the wings.

[0079] The electric propulsion units (151, 152) include, for example, a motor powered by an on-board battery and / or an auxiliary power unit, commonly referred to as an APU.

[0080] Their rotation speed and the pitch of the driven propeller can be precisely controlled by the first computer of the primary electrical controls, according to operating instructions that can be modified by the computer of the secondary electrical controls.

[0081] Located at the wingtips, the thrust or drag of these auxiliary engines benefits from a high lever arm to create yaw and roll effects as part of the generation of an asymmetry, which makes it possible, for the same effect, to reduce the power of these engines compared to a twin-engine aircraft.

[0082] Thus, to simulate the asymmetric behavior of a twin-engine aircraft of 2 x 500 hp (2 x 368 kW), it is possible to use a single-engine aircraft of 120 hp (88.3 kW) and two auxiliary engines, one on each wing end, having a cumulative power of around 100 hp (73.6 kW).

[0083] Typically, auxiliary electric motors are powered by a voltage between 400 volts and 800 volts

[0084] Thus, the power of the auxiliary electric thrusters is significantly lower than that of the main thruster, but they allow for the introduction of greater asymmetry effects or simulated power variations without lowering the power of the main thruster, and thus maintain a certain safety margin with respect to this parameter.

[0085] Although the above examples are limited to the case of a simulated twin-engine aircraft from a single-engine system aircraft, a person skilled in the art understands that these principles can be applied regardless of the number of engines of the simulated aircraft, for example, three-engine or four-engine.

[0086] Compared to a real multi-motor solution, the proposed system offers the following advantages:

[0087] to reduce training costs by using an aircraft with a simple configuration to handle training for a more complex and expensive configuration;

[0088] to reduce the CO2 impact of training flights by at least 50% with equivalent flight time;

[0089] to improve the aerodynamic efficiency of the aircraft compared to a multi-engine aircraft for flights without asymmetry;

[0090] to improve safety and reduce the risks of loss of control, particularly in simulated engine failure situations;

[0091] to offer a possibility of ground flight analysis insofar as all commands pass through a computer for all simulated functions and all control and asymmetry data can be recorded;

[0092] to simulate other motorization cases on the same basis, for example the same principles can be applied to simulate a four-engine vehicle.

Claims

Demands

1. System comprising: an aircraft (100) comprising an onboard cockpit (200) comprising control elements (211, 212, 221, 222) and flight instruments (241, 242), a main thruster (110) and electrical controls configured to move at least one aerodynamic surface (121, 122, 130) and modify at least one parameter of the main thruster as a function of an action on at least one control element; a sensor configured to measure the action on the at least one control element;at least one computer (410, 420, 430) comprising an input port configured to receive a signal (421, 422, 423, 419, 319, 329) from the sensor, an output port configured to output an aerodynamic setpoint signal (425, 426, 430) to an actuator configured to move at least one aerodynamic surface (121, 122, 130) and an engine setpoint signal (412, 413) to modify at least one parameter of the main thruster, a non-volatile memory (411, 421, 431) comprising a control law and a computer program configured to calculate the aerodynamic setpoint and the engine setpoint as a function of the signal from the sensor and the control law; wherein the control law and the computer program are configured to reproduce the behavior of a simulated aircraft comprising more than one main thruster.

2. System according to claim 1, wherein the aircraft (100) is fixed-wing and at least one aerodynamic surface comprises a rudder (130) and at least one aileron (121, 122) on each wing.

3. System according to claim 2, wherein the aircraft is single-engine and the simulated aircraft is twin-engine and wherein the control elements include a thrust control (210) comprising two levers independent of each other and wherein an aerodynamic setpoint signal (319) and an engine setpoint signal (329) are generated as a function of an average angular position and an angular position difference between the two independent levers.

4. System according to claim 3, wherein the two independent levers (211, 212) act on a main thruster power control via a differential gear train configured to move the main thruster power control as a function of the average angular position and the angular position difference between the two independent levers.

5. System according to claim 3, wherein the difference in angular position of the two independent levers (211, 212) produces an aerodynamic setpoint (329).

6. System according to claim 3, wherein the piloting instruments are displayed on at least one computer screen (241, 242) and the display includes a simulated display (245) of conditions of two engines as a function of the average angular position and the difference in angular position between the two independent levers.

7. System according to claim 3, wherein the control elements include an instructor control (290) for triggering a simulated aircraft behavior subjected to an engine failure.

8. System according to claim 3, wherein the control elements include a reset control (291) configured to exit a simulated aircraft mode.

9. System according to claim 2, wherein the aircraft includes an auxiliary electric thruster (151, 152) on each wing and the computer and control law are configured to calculate at least one parameter relating to each auxiliary electric thruster.

10. System according to claim 1, wherein the main propellant (110) is a turboprop.

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