Abstract: A method and a system for determining an angular velocity in turning for a rotary wing aircraft in order to make turns that are coordinated relative to the ground or else relative to the air and in order to manage the transition between ground coordination and air coordination while taking account of the wind to which said aircraft is subjected. Said method serving to determine an angular velocity in yaw by means of an anticipation value A and a correction value B on the basis in particular of speeds of advance of the aircraft relative to the ground Vasol and relative to the air Vaair, of its lateral acceleration GY and of its lateral load factor Ny.

Abstract: A method and a system for engaging hovering flight for a rotary wing aircraft. A first mode of operation makes it possible, while the longitudinal speed UX of the aircraft is greater than a first threshold speed Vthresh1 to approach a stop position S while maintaining track relative to the ground, the flight setpoints of an autopilot being a ground course angle TKsol, a deceleration rate Ga for the forward speed Va of the aircraft, a pitch angle P, and a heading ?. A second mode of operation makes it possible, when the longitudinal speed UX is less than a second threshold speed Vthresh2, to engage hovering flight at the stop position S while maintaining heading, the flight setpoints being the longitudinal speed UX, a lateral speed VY, a vertical speed WZ, and the heading ?, the speeds UX, VY, and WZ being reduced progressively to zero speed.

Abstract: A flight control method and system for a rotary wing aircraft. When the longitudinal speed UX of the aircraft is greater than a first threshold speed Vthresh1, a first mode of operation of the method enables flight to be performed while maintaining track relative to the ground, the flight setpoints of an autopilot being a ground course angle TKsol, a forward speed Va, a pitch angle P, and a heading ?. When the longitudinal speed UX is less than a second threshold speed Vthresh2, a second mode of operation enables flight to be performed while maintaining heading, the flight setpoints being the longitudinal speed UX, a lateral speed VY, a vertical speed WZ, and the heading ?.

Abstract: A flight control system for a rotary wing aircraft, the aircraft following a track Tsol relative to the ground with a ground course angle TKsol, a forward speed Va, a pitch angle P, and a heading ?, the aircraft having one or more rotary wings provided with blades of collective pitch and of cyclic pitch that are variable about respective pitch axes and that are capable of performing movements in rotation and in translation. The flight control system has two control members each provided respectively with at least one movement axis A, B, C, D, and an autopilot for generating control signals. An action on one of the control members relative to one of the movement axes A, B, C, D gives rise independently to a modification to the forward speed Va, to the ground course angle TKsol, or indeed to the pitch angle P by means of the autopilot.

Abstract: A standby instrument (10) for an aircraft, the instrument comprising at least one inertial sensor (1), at least one pressure sensor (2), calculation means (3) connected to said inertial and pressure sensors (1, 2), a display unit (4). Said calculation means (3) are suitable for determining critical flight information for said aircraft, and for displaying said critical flight information on the display unit (4) in the event of a main information system of said aircraft failing. In addition, said standby instrument (10) also incorporates stabilization relationships enabling said calculation means (3) to determine control relationships in order to control the actuators (15) of an autopilot of said aircraft in the event of said autopilot failing. Finally, said calculation means (3) are connected to at least one engine operation computer (5) enabling said instrument (10) to display information about a first limit of the engine on said display unit (4).

Abstract: A device (10) for assisted piloting of an aircraft having a rotary wing with a plurality of second blades (3?) and a propulsion unit with a plurality of first blades (2?). The device includes control means (30, 40) for delivering a movement order (O) for moving in a direction, said device (10) having a processor unit (20) for transforming said order (O) into an acceleration setpoint (C) along said direction, and then for transforming said acceleration setpoint (C) into at least one required longitudinal attitude setpoint (?*) that is transmitted to a first automatic system (26) for maintaining longitudinal attitude by controlling a longitudinal cyclic pitch of the second blades (3?), and into a first required load factor setpoint (Nx*) in a longitudinal direction that is transmitted to a second automatic system (25) for maintaining load factor by controlling the collective pitch of the first blades.

Abstract: A standby instrument (10) for an aircraft, the instrument comprising at least one inertial sensor (1), at least one pressure sensor (2), calculation means (3) connected to said inertial and pressure sensors (1, 2), a display unit (4). Said calculation means (3) are suitable for determining critical flight information for said aircraft, and for displaying said critical flight information on the display unit (4) in the event of a main information system of said aircraft failing. In addition, said standby instrument (10) also incorporates stabilization relationships enabling said calculation means (3) to determine control relationships in order to control the actuators (15) of an autopilot of said aircraft in the event of said autopilot failing. Finally, said calculation means (3) are connected to at least one engine operation computer (5) enabling said instrument (10) to display information about a first limit of the engine on said display unit (4).

Abstract: A method of determining an angular velocity of an aircraft includes measuring the angular velocity using at least one gyro delivering a measured angular velocity signal affected by stochastic noise; measuring the angular acceleration of the aircraft using at least one accelerometer delivering a signal representing the angular acceleration of the aircraft; and using a filtering complementary in a frequency domain to combine a sum of the measured angular velocity signal and the angular acceleration signal so as to obtain a hybrid estimated angular velocity signal with reduced stochastic noise.

Abstract: A method of optimizing the operation of left and right propellers disposed on either side of the fuselage of a rotorcraft including a main rotor. Left and right aerodynamic surfaces include respective left and right flaps suitable for being deflected, yaw stabilization of the rotorcraft being achieved via first and second pitches respectively of the left and right propellers, and the deflection angles of the left and right flaps are adjusted solely during predetermined stages of flight in order to minimize a differential pitch of the left and right propellers so as to optimize the operation of the left and right propellers, the predetermined stages of flight including stages of flight at low speed performed at an indicated air speed (IAS) of the rotorcraft that is below a predetermined threshold, and stages of yaw-stabilized flight at high speed performed at an indicated air speed of the rotorcraft greater than the predetermined threshold.

Abstract: A method of determining an angular velocity of an aircraft includes measuring the angular velocity using at least one gyro delivering a measured angular velocity signal affected by stochastic noise; measuring the angular acceleration of the aircraft using at least one accelerometer delivering a signal representing the angular acceleration of the aircraft; and using a filtering complementary in a frequency domain to combine a sum of the measured angular velocity signal and the angular acceleration signal so as to obtain a hybrid estimated angular velocity signal with reduced stochastic noise.

Abstract: A method of optimizing the operation of left and right propellers disposed on either side of the fuselage of a rotorcraft including a main rotor. Left and right aerodynamic surfaces include respective left and right flaps suitable for being deflected, yaw stabilization of the rotorcraft being achieved via first and second pitches respectively of the left and right propellers, and the deflection angles of the left and right flaps are adjusted solely during predetermined stages of flight in order to minimize a differential pitch of the left and right propellers so as to optimize the operation of the left and right propellers, the predetermined stages of flight including stages of flight at low speed performed at an indicated air speed (IAS) of the rotorcraft that is below a predetermined threshold, and stages of yaw-stabilized flight at high speed performed at an indicated air speed of the rotorcraft greater than the predetermined threshold.

Abstract: The invention relates to a method of piloting a rotorcraft having a plurality of engines for driving at least one lift and propulsion rotor, in which method, so long as the rotorcraft has not reached an optimum climb speed (OCS), a pitch attitude control signal (Upitch) is determined that is adapted so that the rotorcraft accelerates in application of a profile (P1, P2, P3) that varies as a function of the elapsed time and as a function of the operating state of the engines (OEI/AEO).

Abstract: The present invention relates to an autopilot system for a rotary wing aircraft operating relative to at least two pilot axes, which system comprises, for each of the two axes, at least one servo-control relationship providing a respective initial control instruction, with the two relationships having a common target; the system includes combination means (36) for providing a series of control instructions by combining the two initial control instructions (UCV, UTV).

Abstract: The invention relates to a method of piloting a rotorcraft having a plurality of engines for driving at least one lift and propulsion rotor, in which method, so long as the rotorcraft has not reached an optimum climb speed (OCS), a pitch attitude control signal (Upitch) is determined that is adapted so that the rotorcraft accelerates in application of a profile (P1, P2, P3) that varies as a function of the elapsed time and as a function of the operating state of the engines (OEI/AEO).

Abstract: A device for the automatic control of a helicopter may include two objective algorithms associated with the collective axis, each of these algorithms automatically determining a command for operating the collective pitch of the blades of the main rotor of the helicopter. The device may also include two objective algorithms associated with pitching axis that function simultaneously and automatically determine a command for operating the tilting of the disk of the main rotor. A first selection device automatically selects the objective algorithm whose command is used for the collective axis, and a second selection made by the first selection device, the objective algorithm whose command is used for the pitching axis.

Abstract: Device and system for the automatic control of a helicopter. The automatic control device (6) comprises a vertical objective law (A) in respect of the pitching axis, which automatically determines a control command (UT1) for operating the tilting of the disk of main rotor of the helicopter, a speed limitation law (B) for limiting the airspeed of the helicopter with respect to at least one limit value, detection means (10) for automatically detecting whether the airspeed reaches the limit value, and toggling means (11) for, in order to select the objective law (A, B) whose control command (UT1, UT2) is used for the pitching axis, automatically toggling from the first law (A) to the second law (B), when the detection means (10) detect that the airspeed has reached the limit value.

Abstract: Automatic control device for a helicopter and automatic control system comprising such a device.

Abstract: Device and system for the automatic control of a helicopter.