At timing t0, a brake gas (raw material gas) starts to be supplied to an ion beam generator, and the brake gas is fed into a turbo molecular pump. After timing t1, a vent valve is opened intermittently to feed atmospheric air into the turbo molecular pump. The brake gas may be different from the raw material gas. The brake gas is supplied using a gas supply system.

A method of thrust reversal operation according to an example of the present disclosure includes, among other things, permitting an increase in engine power when at least one criterion is not met and a thrust reverser is deployed, and denying the increase in engine power when the at least one criterion is met. A system for thrust reversal is also disclosed.

A bearing spring support/damping apparatus has: a first end portion; a second end portion; and a flexible portion between the first end portion and the second end portion, and further comprising: an outer diameter groove in an outer diameter surface of the second end portion, and a radially and axially outwardly open rebate in the second end portion.

A rotary assembly for driving spool rotation includes a rotor and a flow modifier. The rotor is mechanically coupled to a spool of a gas turbine engine. The flow modifier receives flow from and/or direct flow to the rotor. The rotary assembly permits relative movement between the rotor and the flow modifier to move between: a turbine configuration wherein the rotor receives air from an external air source to drive the spool to rotate; and a compressor configuration wherein the rotor is driven to rotate by the spool and to receive and compress air from the gas turbine engine, and discharge the compressed air for supply to the airframe system. The rotary assembly also includes controller to control relative movement between the rotor and the flow modifier through a range of turbine positions of the turbine configuration to vary a torque applied to the rotor for driving the spool.

A motor drive circuit includes an upper switch, a lower switch connected in series with the upper switch and drives a brushless DC motor, a gate drive circuit that drives the lower switch and a brake circuit that uses an inductive voltage generated by the brushless DC motor to apply a voltage to a gate terminal of the lower switch via the gate drive circuit and turns on the lower switch. The gate drive circuit includes a push element that applies a predetermined source voltage to the gate terminal when on, a pull element that pulls out charge from the gate terminal when on, and a rectifier between the push element and the gate terminal to rectify current in a direction from the push element toward the gate terminal.

A damped anti-rotational system is provided comprising a pawl carrier having an axis of rotation, a pawl pivotably mounted to the pawl carrier on a pivot joint, the pawl having a contact portion and a counterweight portion, a stop pin axially disposed in the pawl carrier and configured to contact the contact portion of the pawl in response to radially inward movement of the pawl, wherein the stop pin is mounted to the pawl carrier at a forward portion of the stop pin and an aft portion of the stop pin, wherein a forward O ring is disposed on the forward portion of the stop pin and an aft O ring is disposed on the aft portion of the stop pin.

An aircraft turbine engine includes a rotating body comprising a compressor rotor and a turbine rotor interconnected by a rotor shaft, the turbine engine being configured to drive a member by said rotor shaft via an epicyclic reduction gear, said epicyclic reduction gear comprising a first element (50) configured to be rotationally secured to said shaft, a second element (56) rotationally secured to said member, and a third element configured to be selectively secured to a stator of the turbine engine and disengaged from the stator, wherein the turbine engine comprises driving means to rotationally drive said third element at a piloted speed when it is disengaged from said stator.

A damped anti-rotational system is provided comprising a pawl carrier having an axis of rotation, a pawl pivotably mounted to the pawl carrier on a pivot joint, the pawl having a contact portion and a counterweight portion, a stop pin axially disposed in the pawl carrier and configured to contact the contact portion of the pawl in response to radially inward movement of the pawl, wherein the stop pin is mounted to the pawl carrier at a forward portion of the stop pin and an aft portion of the stop pin, wherein a forward O ring is disposed on the forward portion of the stop pin and an aft O ring is disposed on the aft portion of the stop pin.

The present disclosure relates to a method of controlling the braking of an aircraft equipped with a landing gear bearing braked wheels, the aircraft being propelled by jet engines and equipped with a thrust reversal system, the method involving the steps of estimating the grip/adhesion of the braked wheels and activating the thrust-reversal system or modulating the reverse-thrust generated by the thrust-reversal system if this system is already activated, based on the estimated grip/adhesion.

A gas turbine engine assembly includes a fan section delivering air into a main compressor section. The main compressor section compresses air and delivers air into a combustion section. Products of combustion pass from the combustion section over a turbine section to drive the fan section and main compressor sections. A gearbox is driven by the turbine section to drive the fan section. A pylon supports the gas turbine engine. An environmental control system includes a higher pressure tap at a higher pressure location in the main compressor section, and a lower pressure tap at a lower pressure location. The lower pressure location being at a lower pressure than the higher pressure location. The lower pressure tap communicates to a first passage leading to a downstream outlet and a compressor section of a turbocompressor. The higher pressure tap leads into a turbine section of the turbocompressor such that air in the higher pressure tap drives the turbine section to in turn drive the compressor section of the turbocompressor. The pylon includes a lowermost surface and the higher pressure tap does not extend above a plane including the lowermost surface. A combined outlet of the compressor section and the turbine section of the turbocompressor intermixes and passes downstream to be delivered to an aircraft use. An environmental control system is also disclosed.