A force sensing element is used in a pressure transducer. The force sensing element includes a flat, disc-type spring having a unitary body that circumscribes a central axis, and a plurality of spirals that are continuous with each other and extend radially outwardly from the central axis. The plurality of spirals includes nested symmetrical flights having walls with a non-uniform thickness, and the disc spring is uniformly deflectable along the central axis in response to force acting on the disc-type spring. The spring is configured to have a high accuracy and a high fatigue life such that the spring is suitable for use in high-pressure applications that may require repeatability while operating with over 10 million cycles of unidirectional or bi-directional axial loading.

Distributed trailing edge wing flap systems are described. An example wing flap system for an aircraft includes a flap and first and second actuators. The flap is movable between a deployed position and a retracted position relative to a fixed trailing edge of a wing of the aircraft. The first and second actuators are configured to move the flap relative to the fixed trailing edge. The first actuator is operatively coupled to the second actuator via a shaft. The first actuator is actuatable via pressurized hydraulic fluid to be supplied from a hydraulic system of the aircraft to the first actuator via a hydraulic module operatively coupled to the first actuator. The first actuator is configured to control movement of the second actuator via the shaft when the hydraulic system and the hydraulic module are functional. The second actuator is actuatable via an electric motor of the second actuator. The electric motor is selectively connectable to an electrical system of the aircraft. The electric motor is connected to the electrical system in response to detection of a failure of the hydraulic system or of the hydraulic module. The second actuator is configured to control movement of the first actuator via the shaft when the electric motor is connected to the electrical system.

A drive unit includes an actuator from which an output rod protrudes at one end of a cylinder and being coupled to a flap of an aircraft, an attachment disposed on the other side of the cylinder, a reaction link coupled to the flap at one end and to the attachment at the other end, and a connection-disconnection section allowing the cylinder and the attachment to be coupled to and separated from each other.

The invention concerns a method for estimating an external force acting on an electrohydrostatic actuator, the actuator comprising a ram including a first chamber, a second chamber and a piston located between the first chamber and the second chamber, a pump capable of injecting fluid into the chambers for controlling a movement of the piston, and an electric motor driving the pump, the method comprising steps of: estimating, by means of at least one state observer (21, 22), a dynamic component and a static component of a difference in equivalent fluid pressure between the first chamber and the second chamber from a rotational speed of the electric motor, a position of the piston and a supply current of the electric motor, estimating the external force by means of a post-processing module (23) as a combination of the estimated dynamic component and static component of the difference in fluid pressure.

A drive unit includes an actuator from which an output rod protrudes at one end of a cylinder and being coupled to a flap of an aircraft, an attachment disposed on the other side of the cylinder, a reaction link coupled to the flap at one end and to the attachment at the other end, and a connection-disconnection section allowing the cylinder and the attachment to be coupled to and separated from each other.

A ground spoiler control architecture for aircraft includes a primary control architecture for providing a roll function, a speed-brake function and a ground spoiler function, and a secondary control architecture for providing the ground spoiler function in the event of a failure of the primary control architecture. The primary and secondary control architectures each include multiple actuators for actuating ground spoilers via independent and redundant signaling paths. Redundant hydraulic accumulators provide pressurized hydraulic fluid to the actuators. A ground spoiler control method includes determining whether the aircraft is on the ground based on the throttle-level-angle and whether any two wheels speeds are active or whether the main landing gear is weighted. Deployment of at least a portion of the ground spoiler panels occurs when and when the main landing gear is on the ground and the aircraft is in a landing configuration based on the throttle-level-angle.

Distributed trailing edge wing flap systems are described. An example wing flap system for an aircraft includes a flap and an actuator. The flap is movable between a deployed position and a retracted position relative to a fixed trailing edge of a wing of the aircraft. The actuator is to move the flap relative to the fixed trailing edge. The actuator is hydraulically drivable via first pressurized hydraulic fluid to be supplied by a hydraulic system of the aircraft. The actuator is also hydraulically drivable via second pressurized hydraulic fluid to be supplied by a local power unit. The local power unit is selectively connectable to an electrical system of the aircraft. The electrical system is to power the local power unit to supply the second pressurized hydraulic fluid.

A SCAS module includes one or more SCAS actuators wherein each SCAS actuator comprises a piston arranged for linear motion within a hydraulic chamber in response to a flow of hydraulic fluid metered by a valve. The piston comprises a flexible rod or quill for providing a linear output along the first axis, the flexible rod or quill being mounted internally within an annular portion of the piston so that a space is defined around the flexible rod or quill. The flexible rod or quill is capable of deforming into the surrounding space in order to accommodate movement of the flexible rod or quill.

In one or more embodiments, a system for predicting health of a hydraulic pump comprises a reservoir tank temperature sensor to measure a temperature of a reservoir tank. The system further comprises a hydraulic pump temperature sensor to measure a temperature of the hydraulic pump. Also, the system comprises a differential pressure sensor to measure a differential pressure across a filter associated with the hydraulic pump. Further, the system comprises a processor(s) to determine a differential temperature by subtracting the temperature of the reservoir tank from the temperature of the hydraulic pump, to compare the differential temperature to a differential temperature threshold, to compare the differential pressure to a differential pressure threshold, and to generate an alert signal indicating failure of the hydraulic pump, when the processor(s) determines that the differential temperature exceeds the differential temperature threshold and the differential pressure exceeds the differential pressure threshold.

A hybrid actuator, having a central longitudinal axis, may include a housing defining a central cavity. The hybrid actuator may also include a piston disposed within the central cavity, the piston comprising a piston head that divides the central cavity into a pressure chamber and an annular chamber. The piston houses a pump configured to pump fluid through a port defined in the piston head between the annular chamber and the pressure chamber to extend a piston rod of the piston from the central cavity, according to various embodiments.