An actuator release mechanism includes: a longitudinal sleeve movable along an axis between a lock and release positions; drive means for causing the longitudinal sleeve to move along the axis; and bias means to bias the longitudinal sleeve to the lock position. The drive means includes: a rotary solenoid having a first direction of rotation and a second direction of rotation; a toggle member having a toggle shaft connected to and rotatable with the rotary solenoid, and a toggle head in engagement with the longitudinal sleeve by pins extending radially inwards from the longitudinal sleeve and a helical guide rail provided on a radially outer surface of the toggle head. The longitudinal sleeve is mounted around the toggle head, such that rotation of the solenoid causes rotation of the toggle member and the guide rails which causes the pin(s) to ride along the guide rail to rotate the sleeve.

There is described a method and system for in-flight start of an engine. The method comprises rotating a propeller; generating electrical power at an electric generator embedded inside a propeller hub from rotation of the propeller; transmitting the electrical power from the electric generator to an engine starter mounted on a core of the engine via an electric power link; and driving the engine with the engine starter to a sufficient speed while providing fuel to a combustor to light the engine to achieve self-sustaining operation of the engine.

A hydraulic control valve includes a sleeve with actuator and biasing member ends and a spool with first and second lands. The sleeve defines a bore extending along a spool movement axis, a source port proximate the stow solenoid end and in communication with the bore, and a supply port between the source port and the biasing end. The spool is slidably disposed within the bore, is movable along the spool movement axis between first and second positions, fluidly separates the source port from the supply port in the first position, and allows the bore to fluidly couple the source port with the supply port in the second position. The first land extends circumferentially about the spool and has a first land length, the second land extending circumferentially about the spool and has a second land length, and the first land length is larger than the second land length.

A ram air turbine (RAT) restow system includes an actuator assembly with a piston interposed between an upper fluid compartment and a lower fluid compartment. The actuator assembly is configured to selectively move the piston between a deployed position and a stowed position. A hydraulic restow circuit is interposed between the actuator assembly and a hydraulic fluid system that is configured to output fluid. The hydraulic restow circuit includes a restow valve configured to operate in a first position that establishes a first fluid path to deliver the fluid to the upper fluid compartment and a second position that establishes a second fluid path to deliver the fluid to the lower fluid compartment.

A ram air turbine release system including a turbine defining a rotational axis including at least one notch therein for receiving a plunger to prevent rotation of the turbine mechanically by moving between a first position and a second position, and a first bearing system contacting at least a portion of an outer surface of the plunger configured to reduce friction produced when the plunder moves between the first positon and the second position.

A toggle release mechanism comprises a platform, a toggle element comprising one or more rolling or sliding elements configured to move along a track between a first, locking position and a second, release position, and a solenoid configured to move the one or more rolling or sliding elements along the track between the first, locking position and the second, release position.

A ram air turbine (RAT) can include a housing and a turbine shaft configured to connect to one or more turbine blades and be turned by the one or more blades. The turbine shaft can be disposed in the housing to rotate relative to the housing along a rotational axis. The RAT can include a first bearing and a second bearing mounted between the turbine shaft and the housing to allow the turbine shaft to rotate relative to the housing. The RAT can include a whirl reduction system configured to dampen or eliminate whirl around the rotational axis.

A protective coating composition for providing protection to a component of a ram air turbine system in need thereof. The protective coating composition comprises an aqueous-soluble or alkaline-soluble polymer matrix, one or more compressible fillers, and one or more non-compressible fillers. The disclosure also provides a method for providing a protective coating onto components of a ram air turbine system in need thereof for providing indentation and scratch resistance thereto.

A containment structure for a rotor includes a shroud and a shroud reinforcement. The shroud is coaxial with and partially surrounds the rotor and includes a tubular section, a transition section, and a flange section. The tubular section extends axially past a first side of the rotor. The transition section connects to the tubular section and is adjacent to a curved side of the rotor. The flange section connects to the transition section opposite the tubular section. The flange section extends radially past a radially outer side of the rotor. The shroud reinforcement is connected to a radially outer surface of the transition section. The shroud reinforcement encloses the transition section and includes a support scaffold and a reinforcing material. The support scaffold includes a series of geometric retaining features encircling a radially outer surface of the transition section. The reinforcing material couples to the support scaffold and restricts shroud radial expansion.

A ram air turbine (RAT) system can include a generator configured to be turned by a RAT and to output an alternating current (AC) power, a generator control unit (GCU) configured to control an output of the generator, a rectifying module configured to rectify the AC power into a direct current (DC) power, and a DC load configured to receive the DC power from the rectifying module. The DC load can be operatively connected to the GCU to provide feedback from the DC load to the GCU. The GCU can be configured to control the output of the generator as a function of the feedback to prevent stalling of the RAT and/or doorbelling current and/or voltage in the system caused by disconnecting the generator from the DC load.