A tiltrotor has a range of motion between a forward flight position and a hovering position, where a pylon and the tiltrotor are coupled via a telescoping actuator, a rigid bottom bar, and a fixed hinge that is attached between the rigid bottom bar and the tiltrotor. The tiltrotor moves from the forward flight position to the hovering position includes extending the telescoping actuator so that the tilt rotor rotates about the fixed hinge.

A landing gear system for an aircraft includes a retractable landing gear assembly, a hydraulic actuator for actuating movement part, for example a bogie of the landing gear assembly, and an accumulator associated with the actuator. The accumulator comprises a volume of pressurised gas separated from hydraulic fluid by a separator piston. Travel of the separator piston beyond a certain position is indicative of a fault. The accumulator includes a snubbing device that acts to slow movement of the separator piston beyond that position. A monitoring system measures the time taken for the movement of the landing gear part effected by the hydraulic actuator. If the measured time is longer than a threshold time, that is indicative of a possible fault in the accumulator, that might, without the snubbing, remain undetected and/or hidden from view.

A landing gear system for an aircraft includes a retractable landing gear assembly, a hydraulic actuator for actuating movement part, for example a bogie of the landing gear assembly, and an accumulator associated with the actuator. The accumulator comprises a volume of pressurised gas separated from hydraulic fluid by a separator piston. Travel of the separator piston beyond a certain position is indicative of a fault. The accumulator includes a snubbing device that acts to slow movement of the separator piston beyond that position. A monitoring system measures the time taken for the movement of the landing gear part effected by the hydraulic actuator. If the measured time is longer than a threshold time, that is indicative of a possible fault in the accumulator, that might, without the snubbing, remain undetected and/or hidden from view.

During a cruise mode, a cruise-only propeller provides thrust using power from a first power source. During a hovering mode and a transitional mode, the propeller provides no thrust. The first power source includes an internal combustion engine; a second power source includes a high discharge rate battery and a high energy battery. The propeller is electrically connected to the first power source and is electrically disconnected from the second power source. During the hovering mode and the transitional mode, a hover-and-transition-only tiltrotor provides thrust using power from the second power source. During a vertical landing, the tiltrotor switches power sources from the high energy battery to the high discharge rate battery, independent of current draw. The tiltrotor is electrically disconnected from the first power source and is electrically connected to the second power source. During the cruise mode, the tiltrotor provides no thrust.

During a cruise mode, a cruise-only propeller provides thrust using power from a first power source. During a hovering mode and a transitional mode, the propeller provides no thrust. The first power source includes an internal combustion engine; a second power source includes a high discharge rate battery and a high energy battery. The propeller is electrically connected to the first power source and is electrically disconnected from the second power source. During the hovering mode and the transitional mode, a hover-and-transition-only tiltrotor provides thrust using power from the second power source. During a vertical landing, the tiltrotor switches power sources from the high energy battery to the high discharge rate battery, independent of current draw. The tiltrotor is electrically disconnected from the first power source and is electrically connected to the second power source. During the cruise mode, the tiltrotor provides no thrust.

A supplemental wing for a rotary wing aircraft rotates about a pitch axis between a forward flight position and a hover position. The supplemental wing generates lift and generates both positive and negative pitching moments that balance and that may passively rotate the supplemental wing to an equilibrium position. The supplemental wing may use power assist to overcome friction to move to the equilibrium position. The lift generated by the supplemental wing reduces at high forward speeds to preserve main rotor control authority. The supplemental wing rotates to avoid aft translation when in the hover position. The supplemental wing may be retrofitted to existing helicopters and flown using existing helicopter controls without pilot re-training.

A supplemental wing for a rotary wing aircraft rotates about a pitch axis between a forward flight position and a hover position. The supplemental wing generates lift and generates both positive and negative pitching moments that balance and that may passively rotate the supplemental wing to an equilibrium position. The supplemental wing may use power assist to overcome friction to move to the equilibrium position. The lift generated by the supplemental wing reduces at high forward speeds to preserve main rotor control authority. The supplemental wing rotates to avoid aft translation when in the hover position. The supplemental wing may be retrofitted to existing helicopters and flown using existing helicopter controls without pilot re-training.

A triplex pneumatic architecture system is disclosed having first, second, and third pneumatic subsystems where triplex redundancy may be accomplished by measuring only one particular node in each system, such as a measured current of the servo valve. Each of the first, second, and third pneumatic subsystems are configured to control a separate redundant pneumatic actuation assembly. Each subsystem may comprise a current sensor to measure a control current from a servo driver to a servo valve that controls the pneumatic actuation assembly to output a measured current value, and a dump valve coupled to a relay. Each processor is configured to generate a termination signal to actuate the first relay to open the first dump valve. The triplex pneumatic architecture system further includes a communication bus to communicatively couple each of the first, second, and third pneumatic subsystems. Each processor is configured to generate the termination signal and to communicate the termination signal to one or more of the relays when one measured current value deviates from the two other measured current values by a predetermined error value.

A triplex pneumatic architecture system is disclosed having first, second, and third pneumatic subsystems where triplex redundancy may be accomplished by measuring only one particular node in each system, such as a measured current of the servo valve. Each of the first, second, and third pneumatic subsystems are configured to control a separate redundant pneumatic actuation assembly. Each subsystem may comprise a current sensor to measure a control current from a servo driver to a servo valve that controls the pneumatic actuation assembly to output a measured current value, and a dump valve coupled to a relay. Each processor is configured to generate a termination signal to actuate the first relay to open the first dump valve. The triplex pneumatic architecture system further includes a communication bus to communicatively couple each of the first, second, and third pneumatic subsystems. Each processor is configured to generate the termination signal and to communicate the termination signal to one or more of the relays when one measured current value deviates from the two other measured current values by a predetermined error value.

A pneumatic actuator can include a housing and an actuator shaft disposed within the housing and configured to actuate between a first position and a second position. The pneumatic actuator can include a single bushing located within the housing between the housing and the actuator shaft. The single bushing can be configured to support the actuator shaft without the actuator shaft being supported at a second location while allowing actuator motion under set operating conditions.