METHOD AND SYSTEM FOR DETECTING INAPPROPRIATE PILOTING RELATED TO SPATIAL DISORIENTATION OF AT LEAST ONE PILOT AND FOR PROTECTING AN AIRCRAFT AGAINST SAID INAPPROPRIATE PILOTING.

Abstract

The invention relates to a system and method for detecting and protecting an aircraft against inappropriate piloting by a pilot potentially experiencing spatial disorientation due to a somatogravic illusion. The method comprises: obtaining (401) flight information and state information; estimating (402) a current value of a perceived degree of longitudinal pitch from said flight information; calculating (403) a difference between said current value of the perceived degree of longitudinal pitch and a current value of an actual degree of longitudinal pitch; and when this difference is greater than or equal to a predetermined longitudinal pitch deviation threshold, then determining (406) whether a piloting action performed by said at least one pilot is inappropriate from the aircraft state information; and when the piloting action performed is inappropriate, then activating (408) a protective measure.It is possible to detect flight conditions conducive to the occurrence of somatogravic illusions, as well as signs of spatial disorientation in pilots leading to inappropriate aircraft piloting. Figure to be published with the abbreviation: Fig. 4.

Description

Title of the invention: METHOD AND SYSTEM FOR DETECTING IMPROPER PILOTING RELATED TO SPATIAL DISORIENTATION OF MINOR A PILOT AND PROTECTION OF AN AIRCRAFT AGAINST SAID IMPROPER PILOTING. technical field

[0001] The scope of this disclosure relates to the protection of an aircraft against improper piloting by the technical flight crew (i.e., a pilot) when the latter is potentially experiencing spatial disorientation due to a "nose-up" type sensory illusion (also known as a longitudinal sensory illusion, a pitch sensory illusion, or a somatogravic illusion). More specifically, this disclosure relates to a method and a system for detecting improper piloting due to spatial disorientation of at least one pilot and for protecting an aircraft against such improper piloting in the event of potential spatial disorientation due to a somatogravic illusion. PRIOR TECHNOLOGY

[0002] Under certain flight conditions, the pilots (i.e., pilot in command and monitoring pilot) of an aircraft may experience spatial disorientation and thus pilot the aircraft inappropriately. This is the case, for example, when the aircraft's accelerations can induce an imprecise sensation of longitudinal attitude (e.g., during the go-around phase, when thrust is at its maximum).

[0003] This spatial disorientation can be caused by so-called "vestibular" sensory illusions, that is, illusions related to the mechanical functioning of the inner ear structures and the physical perception of movement. For example, during the "Go-Around" phase, the pilots' vestibular system undergoes longitudinal and vertical acceleration, which can induce so-called "somatogravic" illusions, also known as "head-up illusions." Pilots may then experience longitudinal spatial disorientation, resulting in an illusion of climbing or descending, and mistakenly interpret the resultant of gravity and inertial forces as a vertical force. In other words, the pilots' vestibular system is affected by the accelerations, which generates a difference in longitudinal attitude (i.e.(pitch attitude, or "actual pitch attitude" in English) of the aircraft and the longitudinal attitude perceived by the pilots.

[0004] This spatial disorientation can be more pronounced in particular in situations where external visual cues are lost (e.g., in clouds, or when rain falls on the aircraft windshield) or in cases of intense stress, where pilots may be highly distracted and no longer refer to external visual cues, which are still available.

[0005] In order to limit the risks associated with spatial disorientation, pilots are trained not to rely on their physical perception, and to carefully monitor and rely on information from the cockpit. However, aircraft incidents and accidents still occur, demonstrating that, despite their training, pilots are subject to the influence of these sensory illusions and may fly an aircraft based on an erroneous physical perception.

[0006] Furthermore, in order to comply with aircraft regulatory and certification requirements, systems exist that allow for a so-called "reduced thrust" go-around, during which longitudinal acceleration is reduced to limit the occurrence of somatogravic illusions during the go-around phase. However, these types of systems do not currently allow for the manipulation of vertical acceleration, which also contributes to the occurrence of sensory illusions (e.g., somatogravic illusions). Therefore, there remains a risk that pilots may experience spatial disorientation.

[0007] In another example, there are information systems that can compare the actual longitudinal attitude with the longitudinal attitude perceived by the pilots (i.e., as perceived by the pilots' vestibular system) and, based on this comparison, issue an alert when flight conditions are likely to cause spatial disorientation of the pilots. It is thus possible to predict when pilots may become disoriented in space and to alert them to this possibility.

[0008] However, current protection systems against inappropriate aircraft piloting related to pilot spatial disorientation only take into account the detection of a risk of spatial disorientation, and not the detection of confirmed cases where the pilot(s) submit to the sensory illusion (e.g., somatogravic illusion) and apply inappropriate piloting actions (e.g., piloting action aimed at ordering a dive of the aircraft which proves inappropriate to the current phase of flight).

[0009] It is therefore desirable to overcome these drawbacks of the state of the art in order to improve the situation by adding protection to what is currently recommended by the Authorities to comply with the new regulatory certification requirements.

[0010] It is particularly desirable to provide a solution that makes it possible not only to detect flight conditions conducive to the appearance of somatogravic illusions, but also to detect situations where pilots actually exhibit Signs of exposure to this somatogravic illusion, such as inappropriate aircraft piloting occurring simultaneously with the detection of such a risk of exposure to a somatogravic illusion, should be considered. Furthermore, it is desirable to provide a solution that allows for the correction of this inappropriate aircraft piloting when the pilot(s) are potentially experiencing spatial disorientation. Description of the invention

[0011] A method for detecting inappropriate piloting related to spatial disorientation caused by a somatogravic illusion experienced by at least one pilot is proposed here, and for protecting an aircraft against such inappropriate piloting. This method is implemented in a detection and protection system comprising electronic circuitry configured to: - obtain flight information and aircraft status information; - to estimate a current value of a perceived degree of longitudinal pitch (perceived), as perceived by said at least one pilot from said flight information obtained, - to calculate a difference between said current value of the perceived degree of longitudinal pitch (perceived) and a current value of an actual degree of longitudinal pitch (actual), which is obtained from the flight information obtained, - and, when the difference between the current value of the perceived degree of longitudinal attitude (9perceived) and the current value of the actual degree of longitudinal attitude (©actual) is greater than or equal to a predetermined threshold of longitudinal attitude deviation (SI) then determine (406) whether a piloting action performed by said at least one pilot is inappropriate from the aircraft state information (100) obtained, - and, when the piloting action performed is inappropriate then activate (408) a protection measure against inappropriate piloting.

[0012] Thus, it is possible not only to detect flight conditions conducive to the occurrence of somatogravic illusions, but also to detect whether pilots succumb to this somatogravic illusion and exhibit signs of spatial disorientation leading to inappropriate aircraft piloting. Consequently, it is possible to activate a protective measure against this inappropriate piloting.

[0013] According to one embodiment, the protection measure is activated when the current value of the actual longitudinal trim degree (©rei) is less than or equal to a predetermined actual longitudinal trim threshold.

[0014] According to one embodiment, activating the protection measure includes: estimating an anticipated projection of a longitudinal attitude, also called dynamic longitudinal attitude (©dyn), expressed according to the following equation:

[0015] Where, - ©real is the actual current degree of longitudinal trim; - K is a gain allowing to weight the dynamics of variation of the actual longitudinal trim degree 0^.

[0016] According to one embodiment, when a current value of the degree of dynamic longitudinal attitude (0dyn) is greater than a predetermined minimum longitudinal attitude threshold, then the protection measure is deactivated, otherwise, a steering command is calculated to correct the inappropriate piloting action of at least one pilot.

[0017] According to one embodiment, the calculated control order is assigned a priority level, and when, following a vote, said priority level of the calculated control order is greater than the priority level of at least one other different protection measure, then this control order is transmitted to control actuators of the aircraft.

[0018] According to one embodiment, when said control command is transmitted to said aircraft control actuators, then, in addition, an alert message is transmitted to alert at least one pilot that said protective measure is activated.

[0019] Also proposed herein is a detection and protection system for detecting inappropriate piloting related to spatial disorientation caused by a somatogravic illusion experienced by at least one pilot and for protecting an aircraft against said inappropriate piloting, said detection and protection system comprising electronic circuitry configured to: - obtain flight information and aircraft status information; - to estimate a current value of a perceived degree of longitudinal pitch (0perceived), as perceived by said at least one pilot from said flight information obtained, - to calculate a difference between said current value of the perceived degree of longitudinal pitch (©Perceived) and a current value of an actual degree of longitudinal pitch (0actual), which is estimated from the flight information obtained, - and, when the difference between the current value of the perceived degree of longitudinal attitude (0perceived) and the current value of the actual degree of longitudinal attitude (0actual) is greater than or equal to a predetermined threshold of longitudinal attitude deviation (SI) then determine (406) whether a piloting action performed by said at least one pilot is inappropriate from the aircraft state information (100) obtained, - and, when the piloting action performed is inappropriate then activate (408) a protection measure against inappropriate piloting.

[0020] An aircraft comprising a detection and protection system as described above is also proposed here.

[0021] A computer program product is also proposed, comprising instructions that cause a processor to execute the process described above in any of its embodiments when said instructions are executed by the processor. A storage medium for storing such instructions is also proposed. Brief description of the drawings

[0022] The features of this disclosure mentioned above, as well as others, will become clearer upon reading the following description of at least one exemplary embodiment, said description being made in relation to the accompanying drawings, among which:

[0023] [Fig-1] schematically illustrates, in side view, an aircraft equipped with a system detection of inappropriate piloting linked to spatial disorientation of at least one pilot and protection of an aircraft against this inappropriate piloting, according to one embodiment;

[0024] [Fig.2] schematically illustrates the system for detecting inappropriate piloting linked to spatial disorientation of at least one pilot and protection of an aircraft against such inappropriate piloting, according to one embodiment;

[0025] [Fig.3] schematically illustrates an example of a hardware platform enabling to implement, in the form of electronic circuitry, the system for detecting inappropriate piloting linked to spatial disorientation of at least one pilot and for protecting an aircraft against this piloting, according to an embodiment;

[0026] [Fig.4] and [Fig.5] schematically illustrate different stages of a process of detection of inappropriate piloting linked to spatial disorientation of at least one pilot and protection of an aircraft against this inappropriate piloting, performed by the detection and protection system, according to an embodiment.

[0027] DETAILED DESCRIPTION OF IMPROVEMENTS

[0028] The general principle of this disclosure relates to the detection of flight conditions that may induce a somatogravic illusion causing spatial disorientation of the pilot(s) of an aircraft, as well as the detection of confirmed spatial disorientation of at least one pilot. This disclosure further relates to the correction of inappropriate piloting actions by the aircraft pilot(s) when they are victims of this spatial disorientation, for example, related to a somatogravic illusion.

[0029] Figure 1 schematically illustrates, in side view, an aircraft 100 equipped with a system 101 for detecting inappropriate piloting linked to spatial disorientation of at least one pilot and for protecting the aircraft 100 against this inappropriate piloting. case of spatial disorientation of at least one pilot (also referred to hereafter as detection and protection system 101), according to one embodiment.

[0030] According to the embodiment of [Fig. 1], the detection and protection system 101 is an electronic device installed in the aircraft 100. For example, the detection and protection system 101 is part of an electronic circuitry of the avionics of the aircraft 100. For example, the detection and protection system 101 is integrated into a flight control computer, denoted CCV. This CCV flight control computer is, for example, a primary flight control computer.

[0031] The detection and protection system 101 is schematically and globally illustrated in [Fig.2], according to one embodiment.

[0032] This detection and protection system 101 comprises: - a first Ml module for monitoring the risk of somatogravic illusion (also called the Ml monitoring module), - a second M2 module for detecting inappropriate action by at least one driver (also called the M2 detection module), - a third M3 protection module against inappropriate piloting of aircraft 100 linked to spatial disorientation of pilots (also called M3 protection module).

[0033] It should be noted that the term "module" can refer to a software component as well as a hardware component or a set of hardware and software components, a software component itself corresponding to one or more computer programs or subprograms or more generally to any element of a program capable of implementing a function or a set of functions.

[0034] The detection and protection system 101 is configured to receive, in real time, from a set of different measurement systems, denoted SYS_MES, flight information representative of flight parameters at a given time t during the flight of aircraft 100. These flight parameters are, for example: the geographical position of aircraft 100, its speed, its heading, its altitude above ground level, its longitudinal attitude (i.e., pitch angle), its longitudinal and / or vertical acceleration in a predefined area around the cockpit of aircraft 100, etc. Each measurement system includes a set of sensors configured to measure, in real time, one or more flight parameters of aircraft 100. For example, these sensors are: accelerometers, pressure sensors, gyroscopes, etc.

[0035] The detection and protection system 101 is further configured to receive, in real time, status information from the aircraft 100 from a set of different avionics systems of the aircraft 100, denoted SYS_AV. This status information is representative of the state parameters of the aircraft 100 at time t of flight. These state parameters are, for example: a position of one or more piloting organs (e.g., “mini-stick”, also called “side-stick” in English) allowing the pilots (i.e., pilot in command and monitoring pilot) of aircraft 100 to act on the longitudinal attitude of the latter, the model of aircraft 100, its mass, a position of its center of gravity, a configuration of the high-lift flaps (“flaps” in English) and the leading slats (“slats” in English), etc.

[0036] According to one embodiment, the detection and protection system 101 can further be configured to transmit an alert message to one or more warning and / or communication systems of the aircraft 100 (not shown in [Fig. 2]), such as: a Flight Warning Computer (FWC), an Electronic Centralized Aircraft Monitoring (ECAM), a Primary Flight Display (PFD), etc. This alert message informs the pilots of the activation of a protective measure against inappropriate piloting of the aircraft 100 related to potential spatial disorientation. In one embodiment, the alert message further informs the pilots that a corrective measure for inappropriate piloting of the aircraft 100 is being executed.

[0037] According to one embodiment, the detection and protection system 101 is further configured to calculate, if necessary, a control command (e.g., an elevator command) to correct the inappropriate action performed by the pilot(s) and to provide this control command to the flight control controller (FCC). The FCC is configured to control the movement, via actuators (not shown in [Fig. 2]), of the aircraft's control surfaces 100, such as the two elevators (denoted GP1 and GP2). In one example, the FCC is configured to transmit the control command calculated by the detection and protection system 101 to the actuators that deflect one or both elevators GP1 and GP2 to a particular angle, adapted to the current flight situation of the aircraft 100 (e.g., an angle adapted for performing a "Go-Around" phase).

[0038] Fig. 3 schematically illustrates an example of a hardware platform for implementing, in the form of electronic circuitry, the detection and protection system 101, according to one embodiment.

[0039] The hardware platform comprises, connected by a communication bus 310, a processor or CPU (Central Processing Unit) 301; a random-access memory (RAM) 302; a read-only memory 303, for example of the ROM (Read Only Memory) or EEPROM (Electrically-Erasable Programmable ROM) type, such as Flash memory; a storage unit, such as a hard disk drive (HDD) 304, or a storage media reader, such as an SD card reader (“Secure Digital” in English); and a COM interface manager 305.

[0040] The COM 305 interface manager allows the detection and protection system 101 to interact with, for example, the set of measurement systems SYS_MES, the set of avionics systems SYS_AV of the aircraft 100. According to one embodiment, the COM 305 interface manager allows the detection and protection system 101 to interact with warning and / or communication systems of the aircraft 100, such as for example: the FWC, the ECAM, the PFD, etc.

[0041] The processor 301 is capable of executing instructions loaded into RAM 302 from ROM 303, external memory, a storage medium (such as an SD card), or a communication network. When the hardware platform is powered on, the processor 301 is capable of reading instructions from RAM 302 and executing them. These instructions form a computer program causing the processor 301 to implement all or part of the steps, processes, or, more broadly, the operating sequences of the aircraft 100 described herein.

[0042] All or part of the steps, processes, and operations described herein can thus be implemented in software form by the execution of a set of instructions by a programmable machine, for example, a DSP (Digital Signal Processor) or a microcontroller, or implemented in hardware form by a dedicated machine or electronic component (chip) or a dedicated set of electronic components (chipset), for example, an FPGA (Field Programmable Gate Array) or ASIC (Application-Specific Integrated Circuit). Generally speaking, the detection and protection system 101 comprises electronic circuitry adapted and configured to implement all or part of the operations, processes, and steps described herein.

[0043] It is presented in connection with [Fig. 4], in the form of a diagram of the steps of a method for detecting inappropriate piloting related to spatial disorientation of at least one pilot and for protecting the aircraft 100 against this inappropriate piloting when at least one pilot potentially experiences spatial disorientation (also referred to hereafter as the "detection and protection method"), according to one embodiment. All or part of this detection and protection method is implemented by the detection and protection system 101 described above.

[0044] Subsequently, by way of example, the implementation of the detection and protection method is carried out under flight conditions corresponding to a "Go-Around" phase. Indeed, as previously presented, the longitudinal and vertical acceleration conditions of the "Go-Around" phase are conducive to the occurrence somatogravic illusions can lead to spatial disorientation of pilots and therefore potentially inappropriate piloting of aircraft 100. It should be noted that the detection and protection process can be implemented in flight conditions other than those corresponding to the go-around maneuver (also called the "Go-Around" phase).

[0045] From the start of the flight of aircraft 100, that is to say as soon as aircraft 100 is no longer in contact with the ground, during a step 401, noted R_INFO, the detection and protection system 101 obtains, in real time, from all the measurement systems SYS_MES and all the avionics systems SYS_AV of aircraft 100, flight information and state information representative, respectively, of flight parameters and state parameters of aircraft 100.

[0046] In one embodiment, the measurement systems and avionics systems transmit this flight information and aircraft state information 100 to the detection and protection system 101 at a predetermined frequency. The predetermined frequency depends on the capabilities of the probes or sensors of each aircraft. In a particular embodiment, this predetermined frequency depends on the nature of the parameter (i.e., flight parameter or state parameter). In one example, the transmission frequency of flight information representative of a flight parameter such as longitudinal acceleration is eight points per second.

[0047] According to one embodiment, each flight or state information is filtered according to predetermined filtering criteria. For example, these filtering criteria depend on the nature of the flight or state parameter. This makes it possible to avoid the untimely detection of flight conditions conducive to the manifestation of spatial disorientation in pilots. Consequently, it is possible to avoid the inadvertent activation of a protective measure for aircraft 100 against inappropriate piloting of aircraft 100.

[0048] During a flight conditions monitoring phase, the detection and protection system 101, via the monitoring module M1, detects flight conditions conducive to the occurrence of somatogravic illusions during the "Go-Around" phase. In particular, according to one embodiment, the detection and protection system 101 monitors the longitudinal attitude of the aircraft 100.

[0049] To this end, during a step 402, denoted DET_Op, the detection and protection system 101, via the monitoring module Ml, estimates a current value (i.e., at time t) of one degree of the longitudinal attitude perceived by the pilots (hereinafter "perceived degree of longitudinal attitude" or "perceived longitudinal attitude"), denoted 0perceived (i.e., perceived pitch attitude degree), according to the following formula EQ1:

[0050] „ . , 0perçu — Arctam jy- I \ ' *wckpil !

[0051] Where,

[0052] - Nxlcockpit is a measure at time t of the longitudinal acceleration of the aircraft 100, in the aircraft reference frame 100, and measured in a predefined area around the cockpit (e.g., using accelerometers at the front of the aircraft 100 or installed on the cockpit);

[0053] - Nzlcockpit is a measurement at time t of the vertical acceleration of the aircraft 100, in the aircraft 100 reference frame, and measured in the predefined area around the cockpit (e.g., using accelerometers at the front of aircraft 100 or installed on the cockpit).

[0054] This current value of perceived degree of longitudinal attitude corresponds to an estimated value of the aircraft's longitudinal attitude 100 felt by the pilots' vestibular system (at the level of their head position).

[0055] Then, during a step 403, denoted COMP_DIFF_S1, the detection and protection system 101, via the monitoring module M1, determines that a current flight condition is conducive to the occurrence of somatogravic illusions in the pilots. To do this, the detection and protection system 101 calculates the difference between a current value of the perceived pitch attitude (perceived pitch attitude) and a current value of the actual pitch attitude (hereinafter "actual pitch attitude"), denoted δrei (i.e., actual pitch attitude). This difference corresponds to the discrepancy between the pilots' perception of the aircraft's pitch attitude and the aircraft's actual pitch attitude. It should be noted that the actual pitch attitude (δrei) is measured by a sensor, such as a gyroscope.

[0056] This difference between the current value of the perceived longitudinal pitch angle (perceived) and the current value of the actual longitudinal pitch angle (actual pitch angle) is then compared to a predetermined longitudinal pitch deviation threshold, denoted SI. The order of magnitude of this predetermined longitudinal pitch deviation threshold SI is between 5° and 10°. The aim here is to monitor the difference between the perception by the crew of aircraft 100 and the actual longitudinal pitch angle of aircraft 100.

[0057] In a particular embodiment, this predetermined threshold of longitudinal attitude deviation SI depends on the altitude of the aircraft 100 relative to the ground, at a given instant, denoted instant t.

[0058] Thus, if the difference between the current value of the perceived longitudinal trim degree ©perceived and the current value of the actual longitudinal trim degree ©reali is less than the predetermined longitudinal trim deviation threshold SI (i.e., "no" response at the end of step 403), then this step 403 COMP_DIFF_S 1 is repeated.

[0059] On the contrary, if this difference is greater than or equal to the predetermined threshold of longitudinal attitude deviation SI (i.e., "yes" response at the end of step 403), then the detection and protection system 101 executes a step 405, denoted 403_AND_404. Thus, when the perceived longitudinal attitude 0perceived by the pilots is greater than the actual longitudinal attitude 0real (i.e., as measured by one or more appropriate sensors), beyond the predetermined threshold of longitudinal attitude deviation SI, there is a risk that the pilots will suffer from spatial disorientation related to a somatogravic illusion.

[0060] During step 404, denoted COMP_Or_S2, which takes place synchronously or asynchronously with step 403 COMP_DIFF_S1 described above, the detection and protection system 101, via the monitoring module M1, compares a current value of the actual longitudinal pitch angle 0rei to a predetermined threshold of actual longitudinal pitch, denoted S2. The order of magnitude of this predetermined threshold of actual longitudinal pitch S2 is between 5 and 12°. This makes it possible to avoid inappropriate detections of flight conditions conducive to the occurrence of somatogravic illusions in pilots.

[0061] In a particular embodiment, this predetermined threshold of actual longitudinal attitude S2 depends on the altitude of the aircraft 100 relative to the ground at time t.

[0062] If the current value of the actual longitudinal trim degree 0rei is greater than the predetermined threshold of actual longitudinal trim S2 (i.e., a "no" response at the end of step 404), then step 404 is repeated. If, on the contrary, the current value of the actual longitudinal trim degree 0rei is less than or equal to the predetermined threshold of actual longitudinal trim S2 (i.e., a "yes" response at the end of step 404), then the detection and protection system 101 executes step 405, denoted 403_AND_404.

[0063] During step 405, noted 403_ET_404, the detection and protection system 101, via the monitoring module M1, verifies that at time t, at the end of step 404 COMP_0r_S2, the actual longitudinal trim 0réei is less than or equal to the predetermined threshold of actual longitudinal trim S2 (i.e., answer "yes" at the end of step 404) and that, in addition, the difference between the perceived longitudinal trim 0perÇu and the actual longitudinal trim 0réei is greater than or equal to the predetermined threshold of longitudinal trim deviation SI (i.e., answer "yes" at the end of step 403). If both of these conditions are met (i.e., "yes" answer at the end of step 404 and "yes" answer at the end of step 403), then the 101 detection and protection system detects that the current flight condition is conducive to the occurrence of somatogravic illusions in pilots.

[0064] During a monitoring phase of the piloting of aircraft 100, the detection and protection system 101, via the detection module M2, determines whether piloting of aircraft 100 by at least one pilot is inappropriate. More specifically, when flight conditions conducive to the onset of somatogravic illusions in pilots are detected at the end of the flight conditions monitoring phase, then the detection and protection system 101 determines whether piloting of aircraft 100 by at least one pilot is inappropriate.

[0065] To this end, during a step 406, denoted DET_ACT_EQ, the detection and protection system 101, via the detection module M2, detects, at time t, that a piloting action on at least one control component of the aircraft 100 is performed by at least one pilot. The detection and protection system 101 then determines whether this piloting action is inappropriate (i.e., unsuitable) with regard to the current flight phase (e.g., go-around phase).

[0066] In one example, when aircraft 100 is in a go-around phase, this so-called "inappropriate" piloting action is an action aimed at inducing a dive of aircraft 100 in order to decrease its pitch attitude (whereas an appropriate action would be to decrease the pitch attitude to stabilize in level flight). To this end, the detection and protection system 101 receives, from one or more avionics systems of aircraft 100 belonging to the SYS_AV avionics suite, state information representing a state parameter of aircraft 100 such as the position of the control instruments used to control the pitch attitude of aircraft 100.

[0067] Thus, in this example, if the detection and protection system 101 does not detect any action on the piloting instruments by the pilots or if a piloting action is detected, but it is not inappropriate with regard to the state of the aircraft 100, and in particular the longitudinal attitude of the aircraft (i.e., a "no" response at the end of step 406), then step 406 is repeated. Conversely, if the detection and protection system 101 detects that an inappropriate piloting action, for example an inappropriate nose-down (longitudinal) action on at least one piloting instrument (e.g., an action aimed at ordering a nose-down of aircraft 100 using a piloting instrument, such as a mini-stick) is performed by at least one pilot while the longitudinal attitude of aircraft 100 is already low (i.e., a "yes" response at the end of step 406), then the detection and protection system 101 executes a step 407, noted 403_ET_404_ET_406.

[0068] Furthermore, when an inappropriate piloting action on at least one piloting element is detected, the detection and protection system 101 performs a time delay that allows time for the pilots to react themselves and correct this inappropriate piloting action. In one example, the system detection and protection 101 changes a variable i from a value 0 to 1 by applying a delay (in seconds), noted T, predetermined fixed (e.g., 2 to 8 s) and / or dependent on the altitude of the aircraft 100 and the actual longitudinal attitude ©real.

[0069] Following the flight condition monitoring phases (i.e., steps 402 to 405) and the aircraft 100 piloting monitoring phases (i.e., step 406), during step 407, denoted 403_ET_404_ET_406, the detection and protection system 101 verifies: - that at the end of step 404 COMP_©r_S2, the actual longitudinal attitude ©real_i is less than or equal to the predetermined actual longitudinal attitude threshold S2 (i.e., "yes" at the end of step 404) and, - that the difference between the perceived longitudinal attitude ©perceived and the actual longitudinal attitude ©real_i is greater than or equal to the predetermined longitudinal attitude deviation threshold SI (i.e., "yes" at the end of step 403), and - that an inappropriate piloting action, for example, on at least one control element is performed by at least one pilot (i.e., "yes" answer at the end of step 406).

[0070] Thus, when the preceding conditions are met (i.e., a "yes" response at the end of steps 403, 404 and 406), then the detection and protection system 101 detects that the pilot(s) are potentially experiencing spatial disorientation and are piloting the aircraft 100 inappropriately, probably because of this spatial disorientation.

[0071] It is thus possible, by comparing an estimate of the longitudinal attitude of aircraft 100 as perceived by the pilots (©pe,Çu) to the actual longitudinal attitude of aircraft 100 (ôréei), to detect a situation where the pilot is potentially a victim of somatogravic illusions, and, relying no doubt on his own feeling rather than on his instruments or on the alerts of the various systems (e.g., Ground Proximity Warning System or GPWS), performs inappropriate piloting actions (e.g., actions aimed at ordering a dive of aircraft 100) which can, in the end, lead to the destruction of aircraft 100 by contact with the ground (or Control Flight Into Terrain or CFIT).

[0072] As a result, the detection and protection system 101, via the protection module M3, activates, during a step 408 denoted PRO_ON, the aircraft protection measure 100 against improper piloting (also referred to hereafter as "protection measure").

[0073] It is presented in relation to [Fig. 5], in the form of a diagram of the steps of the detection and protection process after activation of the protection measure (i.e., step 408 PRO_ON), ​​according to one embodiment. Steps 501 and 504 described above- then are implemented by the M3 detection module of the 101 detection and protection system.

[0074] When this protection measure is activated (i.e., step 408 PRO_ON), ​​then, during a step 501, denoted DET_Od, the detection and protection system 101 estimates an anticipation of the actual longitudinal attitude of the aircraft 100, taking into account its current evolution at time t, called dynamic longitudinal attitude denoted ôdyn from the following formula EQ2: 100751

[0076] Where,

[0077] - K is a gain that allows for taking into account the dynamic variation of the actual longitudinal plate ©real.

[0078] Estimating the dynamic longitudinal attitude ©dyn allows the protective measure to be adapted. For example, if the actual longitudinal attitude of aircraft 100 is returning to more reasonable values, it is not necessary to intervene as strongly as if the actual longitudinal attitude of aircraft 100 continues to decrease.

[0079] After estimating the dynamic longitudinal attitude, denoted ôdyn, the detection and protection system 101 compares the dynamic longitudinal attitude ©dyn to a predetermined minimum longitudinal attitude threshold, denoted S3.

[0080] In a particular embodiment, this predetermined minimum longitudinal attitude threshold S3 depends on the altitude of the aircraft 100 relative to the ground at time t.

[0081] When a current value of the dynamic longitudinal attitude ©dyn is greater than the predetermined minimum longitudinal attitude threshold S3 (i.e., a "yes" response at the end of step 501), then the protection measure is deactivated during a step 502, denoted PRO_OFF. Consequently, the detection and protection system 101 does not calculate any control commands to correct the actual longitudinal attitude of aircraft 100 in response to inappropriate piloting of aircraft 100. The protection measure is no longer active since aircraft 100 has reached the target minimum longitudinal attitude (i.e., the predetermined actual longitudinal attitude threshold 0réei). In other words, depending on the difference between the actual longitudinal attitude (©réei) and the target minimum longitudinal attitude (i.e., the predetermined actual longitudinal attitude threshold ©réei), the protection measure remains active or not.

[0082] Conversely, when a current value of the dynamic longitudinal trim ôdyn is less than the predetermined minimum longitudinal trim threshold S3 (i.e., a "no" response at the end of step 501), then the detection and protection system 101 executes a step 503, denoted CALC_GOUV. In other words, the protection measure executed by the detection and protection system 101 allows, where applicable, the calculation of a steering command aimed at correcting the longitudinal attitude of aircraft 100 in response to inappropriate piloting action of aircraft 100 by the pilot(s).

[0083] During step 503 CALC_GOUV, the detection and protection system 101 calculates this control command for control actuators, such as the elevators, in order to correct the longitudinal attitude of the aircraft 100 in response to inappropriate piloting action of the aircraft 100 by the pilot(s).

[0084] This control command is calculated from certain flight information and state information obtained previously during step 401 R_INFO. In particular, this control command depends on the value at time t of the actual longitudinal attitude @réeb of the aircraft model type 100, the mass of aircraft 100 and its center of gravity at time t, the configuration of the high-lift flaps and leading-edge slats, and the value, at time t, of various other flight parameters and state parameters of aircraft 100. This control command further depends on the predetermined minimum longitudinal attitude threshold S3. In one example, this control command corresponds to a command to pitch up aircraft 100 to counteract an inappropriate pitch-down command from at least one pilot until aircraft 100 is brought back to a longitudinal attitude such that:

[0085] - the immediate risk of CFIT can be considered sufficiently reduced;

[0086] - the difference between the actual longitudinal attitude of the aircraft 100 and the longitudinal attitude perceived by pilots reduces the risk of experiencing spatial disorientation.

[0087] Thus, the activation of the protection measure includes:

[0088] - estimating a dynamic longitudinal pitch (0dyn);

[0089] - check for a difference between the current value of the dynamic longitudinal trim (0dyn) ) of the aircraft and a predetermined minimum longitudinal attitude threshold S3;

[0090] - where appropriate, calculate a steering command (e.g., a steering command of depth) to correct inappropriate piloting action by at least one pilot (e.g., to pitch the aircraft up).

[0091] At the end of step 503 CALC_GOUV, the steering command calculated by the detection and protection system 101 is assigned a priority level, for example by a voting module of an avionics system of aircraft 100. This priority level depends, for example, on decision criteria such as the command that intends to make aircraft 100 pitch up the most will have the highest priority level.

[0092] The priority level of the control command calculated by the detection and protection system 101 is then compared to other priority levels assigned to other protection measures by different avionics protection systems of the aircraft 100 (e.g., the protection measure described in the Applicant's patent application published under number FR2986876 and describing an automatic aircraft protection measure against a risk of collision with the ground or sea called GCoP (acronym for " Ground Collision Protection (GCP), meaning "Protection against a collision with the ground" in French. These other protective measures also aim to transmit a steering command for the actuation of the elevators.

[0093] To select the control command to be applied, the voting module of an aircraft avionics system 100 compares, for example, the priority levels of the different control commands calculated by the various protection measures. Thus, the control command with the highest priority level is selected as the priority by the voting module, and this is the command that is applied.

[0094] If the priority level of the control command calculated by the detection and protection system 101 is higher than the priority level of other protection measures (e.g., the control command calculated for the GCoP protection measure), then the control command calculated by the detection and protection system 101 takes precedence. Consequently, the detection and protection system 101 executes a correction measure for the inappropriate pilot action, corresponding to a transmission of the previously calculated control command to the control actuators, such as the aircraft's elevators 100, via the CCV flight control computer, during a step 504 denoted TRANS_GOUV.Conversely, if the priority level of the control command calculated by the 101 detection and protection system is lower than the priority level of other protection measures, then this control command is not transmitted, and the control command from another protection measure is then transmitted to the elevators, for example. If the control command calculated by the 101 detection and protection system does not have priority, this means either that another, more important pitch-up command has been sent by another protection system, or that the pitch-up command is too important and has lower priority than a pitch-down command (which generally remains the priority to protect the aircraft from a potential stall).

[0095] According to one embodiment, the detection and protection process ends after the transmission of the steering commands.

[0096] It should be noted that the protective measure described above should not prevent the pilot from landing the aircraft 100. Indeed, as indicated above, this protective measure is only activated in the event of a potential somatogravic illusion situation detected, which should not be the case when the pilot wants to land because then, the longitudinal acceleration of the aircraft 100 (main contributor to the somatogravic illusion phenomenon) is low due to the selection of a reduced thrust level for the landing maneuver.

[0097] Thus, thanks to this protective measure implemented by the detection and protection system 101, it is possible to complement the current systems, already implemented in certain aircraft, which aim to limit longitudinal acceleration during phase of go-around. In particular, this protective measure allows, where appropriate, the application of the corrective measure described above, in order to correct the inappropriate piloting action of the pilot(s).

[0098] In a particular embodiment, during step 504 TRANS_GOUV, when the steering command calculated by the detection and protection system 101 takes precedence, then the detection and protection system 101 could generate an alert message for the pilots and transmit it to the warning and / or communication systems of the aircraft 100. This alert message would aim to inform the pilots of the activation of the protection measure against improper piloting of the aircraft 100. According to a particular embodiment, the alert message would also announce the execution of the corrective measure for the improper piloting action. The detection and protection system 101 would transmit this alert message to warning and / or communication systems of aircraft 100, such as ECAM, PFD or FWC... so that this alert message is displayed and / or broadcast on a Human-Machine Interface of the cockpit of aircraft 100.In one example, this alert message would be a visual and / or audible notification in the form of a warning or advisory caution. Thus, the activation of this protective measure, as well as, where applicable, the execution of the corrective action for the inappropriate piloting action, would be accompanied by the display and / or broadcast of an alert message to the pilots to warn them of the activation of this protective measure and, where applicable, to encourage the pilots to stop applying inappropriate pitching commands.

[0099] It should be noted that experience shows that in cases of intense stress, and particularly in cases where the pilot exhibits attentional tunneling, a warning message alone would not be useful and would be secondary to the protective (compensatory) measure. It is therefore possible to combine the warning message with the protective measure implemented by the detection and protection system 101, this protective measure thus being the primary means of reducing the risk of loss of control of aircraft 100.

[0100] In a particular embodiment, in addition to the predetermined minimum longitudinal attitude threshold S3, a predetermined minimum radio altitude threshold S4 is used. Thus, the lower the radio altitude, the more rapidly the detection of a flight condition conducive to the occurrence of somatogravic illusion must be confirmed. Consequently, it is possible to limit this detection as a function of the aircraft's altitude 100 at time t.

Claims

Demands

1. Method for detecting inappropriate piloting related to spatial disorientation due to a somatogravic illusion experienced by at least one pilot and for protecting an aircraft (100) against such inappropriate piloting, said method being implemented in a detection and protection system (101) comprising electronic circuitry configured to: - obtain (401) flight information and aircraft (100) status information;- estimate (402) a current value of a perceived degree of longitudinal attitude (perceived), as perceived by said at least one pilot from said flight information obtained, - calculate (403) a difference between said current value of perceived degree of longitudinal attitude (perceived) and a current value of an actual degree of longitudinal attitude (actuali), which is obtained from the flight information obtained, - and, when the difference between the current value of perceived degree of longitudinal attitude (perceived) and the current value of actual degree of longitudinal attitude (actuali) is greater than or equal to a predetermined threshold of longitudinal attitude deviation (SI) then determine (406) whether a piloting action performed by said at least one pilot is inappropriate from the aircraft state information (100) obtained, - and, when the piloting action performed is inappropriate then activate (408) a protective measure against inappropriate piloting.;

2. A protection method according to claim 1, wherein said protection measure is activated when the current value of the actual longitudinal trim degree (©reali) is less than or equal to a predetermined threshold of actual longitudinal trim (S2).

3. A protection method according to claim 1 or 2, wherein activating said protection measure comprises: estimating an anticipated projection of a longitudinal trim, also called dynamic longitudinal trim (Δdyn), expressed according to the following equation: Δdyn = Δrei + Δr where, - Δr is the actual current degree of longitudinal trim; - K is a gain allowing to weight the dynamics of variation of the actual longitudinal trim degree @real.

4. A protection method according to claim 3, wherein when a current value of the degree of dynamic longitudinal trim (0dyn) is greater than a predetermined minimum longitudinal trim threshold (S3), then the protection measure is deactivated, otherwise, a rudder command is calculated to correct the inappropriate piloting action of at least one pilot.

5. A protection method according to claim 4, wherein the calculated steering order is assigned a priority level, and wherein, when, as a result of a vote, said priority level of the calculated steering order is greater than the priority level of at least one other different protection measure, then said steering order is transmitted to aircraft steering actuators (100).

6. A protection method according to claim 5, wherein when said control command is transmitted to said aircraft control actuators (100), then an alert message is transmitted to alert at least one pilot that said protection measure is activated.

7. Detection and protection system (101) for detecting improper piloting related to spatial disorientation due to a somatogravic illusion experienced by at least one pilot and for protecting an aircraft (100) against such improper piloting, said detection and protection system (101) comprising electronic circuitry configured to: - obtain (401) flight information and aircraft (100) status information;- estimate (402) a current value of a perceived degree of longitudinal attitude (cp,cu) - as perceived by said at least one pilot from said flight information obtained, - calculate (403) a difference between said current value of the perceived degree of longitudinal attitude (cp,cu) and a current value of an actual degree of longitudinal attitude (cp,cu), which is obtained from the flight information obtained, - and, where the difference between the current value of the perceived degree of longitudinal attitude (cp,cu) and the current value of the actual degree of longitudinal attitude (cp,cu) is greater than or equal to a predetermined threshold of longitudinal attitude deviation (cp,cu) then determine; (406) if a piloting action performed by said at least one pilot is inappropriate based on aircraft state information (100) obtained, - and, where the piloting action performed is inappropriate then activate (408) a protection measure against improper piloting.

8. Aircraft (100) comprising a detection and protection system (101) according to claim 7.

9. Product computer program, comprising instructions causing a processor to execute the method according to any one of claims 1 to 6, when said instructions are executed by the processor.

10. Storage medium, storing a computer program comprising instructions causing a processor to execute the method according to any one of claims 1 to 6, when said instructions are read and executed by the processor.

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