A method of controlling at least one first propeller of a hybrid helicopter, the hybrid helicopter having a thrust control for controlling a first pitch of the first blades of the first propeller. The thrust control includes a movable control member. The method includes the following steps: the thrust control continuously transmitting a control signal carrying a control setpoint to the control system; the control system transforming the control setpoint into a pitch setpoint; and the control system controlling the first pitch by applying the pitch setpoint.

A method of providing torque protection and/or thrust protection for the or each propeller of a hybrid helicopter. The hybrid helicopter includes a control system connected to the blades of each propeller and a thrust control configured to generate an order for modifying a pitch of the blades, which order is transmitted to the control system, the propeller(s) being driven in rotation by a mechanical transmission system of the hybrid helicopter. The method includes a step of having the control system keep the pitch of the blades of a propeller within at least one control envelope relating to a thrust generated by the propeller or to a torque exerted in the mechanical transmission system. In this way, the pitch of the blades of each propeller is kept between a lower limit and an upper limit of the control envelope.

A method of providing torque protection and/or thrust protection for the or each propeller of a hybrid helicopter. The hybrid helicopter includes a control system connected to the blades of each propeller and a thrust control configured to generate an order for modifying a pitch of the blades, which order is transmitted to the control system, the propeller(s) being driven in rotation by a mechanical transmission system of the hybrid helicopter. The method includes a step of having the control system keep the pitch of the blades of a propeller within at least one control envelope relating to a thrust generated by the propeller or to a torque exerted in the mechanical transmission system. In this way, the pitch of the blades of each propeller is kept between a lower limit and an upper limit of the control envelope.

Systems for wing structure and attachment to frame for Unmanned Autonomous Vehicle (UAV) are disclosed herein. In one embodiment, a UAV includes an H-frame having a wing spar secured to two or more boom carriers. The wing spar includes two or more mounting locations, where each of the two or more mounting locations of the wing spar secures a horizontal propulsion unit. The boom carriers include a plurality of mounting locations, each of the plurality of mounting locations of the boom carriers securing a vertical propulsion unit. The UAV also includes a pre-formed wing shell attached to the H-frame.

A method for optimizing the operation of at least one first propeller and of at least one second propeller of a hybrid helicopter. The method comprises the following step during a control phase: deflection, with an autopilot system, of at least one aerodynamic stabilizer member into a setpoint position having, with respect to a reference position, a target deflection angle that is a function of a setpoint deflection angle, the setpoint deflection angle being calculated by the autopilot system in order to compensate for a torque exerted by the lift rotor at zero sideslip.

An unmanned aerial vehicle (UAV) is provided including a fuselage, a pair of wings extending outwardly from the fuselage, and a deployable surface moveable from a first undeployed position during normal flight to a second deployed position when there is a system failure during flight. A method of adjusting a center of pressure of a UAV is also provided including the steps of providing a UAV with a fuselage, a pair of wings extending outwardly from the fuselage, and a deployable surface moveable from a first undeployed position during normal flight to a second deployed position when there is a system failure during flight, sensing when there is a system failure, and moving the deployable surface from the first undeployed position to the second deployed position.

An unmanned aerial vehicle (UAV) is provided including a fuselage, a pair of wings extending outwardly from the fuselage, and a deployable surface moveable from a first undeployed position during normal flight to a second deployed position when there is a system failure during flight. A method of adjusting a center of pressure of a UAV is also provided including the steps of providing a UAV with a fuselage, a pair of wings extending outwardly from the fuselage, and a deployable surface moveable from a first undeployed position during normal flight to a second deployed position when there is a system failure during flight, sensing when there is a system failure, and moving the deployable surface from the first undeployed position to the second deployed position.

A control circuitry includes a first filter configured to filter a gravity compensated longitudinal acceleration of an aircraft to generate a filtered gravity compensated longitudinal acceleration. The propulsor trim control circuitry also includes a second filter configured to generate a filtered speed of the aircraft based on a speed of the aircraft. The propulsor trim control circuitry includes intermediary circuitry configured to generate a filtered longitudinal control effector error based on the filtered gravity compensated longitudinal acceleration and the speed. The propulsor trim control circuitry also includes a third filter configured to generate a filtered longitudinal thrust effector command value based on a longitudinal thrust effector command value. The propulsor trim control circuitry further includes output circuitry configured to generate a predicted longitudinal thrust effector trim value for a target horizontal state based on the filtered longitudinal control effector error and the filtered longitudinal thrust effector command value.

A control circuitry includes a first filter configured to filter a gravity compensated longitudinal acceleration of an aircraft to generate a filtered gravity compensated longitudinal acceleration. The propulsor trim control circuitry also includes a second filter configured to generate a filtered speed of the aircraft based on a speed of the aircraft. The propulsor trim control circuitry includes intermediary circuitry configured to generate a filtered longitudinal control effector error based on the filtered gravity compensated longitudinal acceleration and the speed. The propulsor trim control circuitry also includes a third filter configured to generate a filtered longitudinal thrust effector command value based on a longitudinal thrust effector command value. The propulsor trim control circuitry further includes output circuitry configured to generate a predicted longitudinal thrust effector trim value for a target horizontal state based on the filtered longitudinal control effector error and the filtered longitudinal thrust effector command value.

A rotorcraft including a first power plant, at least one main rotor participating at least in providing lift for the rotorcraft in the air, and at least one tail rotor carried by a tail boom, the first power plant including at least one engine. In accordance with the invention, the rotorcraft includes: at least one pusher or puller propeller independent from the at least one main rotor, the at least one pusher or puller propeller participating at least in providing propulsion or traction for the rotorcraft; a second power plant including at least one electric motor; and at least one control member configured to generate a control setpoint or instruction for controlling the at least one electric motor.