A bleed air valve comprises a housing that includes an inlet, an outlet, and a center portion to selectively provide a pneumatic flow path between the inlet and the outlet. A piston moves along a center guide in response to forces applied to the piston, where the piston is spring biased to an open position. The valve also comprises a pressure regulator valve that comprises a spring loaded poppet valve that includes a pressure regulator inlet that receives an inlet pressure which is regulated based upon force applied to a pressure regulator piston. A valve spring applies a force to the piston first surface to spring bias the bleed air valve to the open position. A solenoid valve receives a command signal and in response provides compressed air to a solenoid valve outlet that is in fluid communication with the pressure regulator inlet.

An apparatus for use in a gas turbine engine is disclosed comprising a bleed valve and an intermediate valve. In use the bleed valve is exposed to a source of pressurised air, and the bleed valve is movable between an open position, in which the bleed valve permits a flow of the pressurised air through the bleed valve and a closed position, in which the bleed valve does not permit a flow of the pressurised air through the bleed valve. The intermediate valve is operatively connected to the bleed valve and configured to selectively open and close the bleed valve, wherein the intermediate valve is configured in a mode of operation to close the bleed valve based on the pressurised air within the bleed valve exceeding a predetermined threshold.

A variable bleed valve system for use in a turbofan engine includes a plurality of circumferentially spaced variable bleed valve assemblies. Each variable bleed valve assembly includes a plurality of circumferentially spaced variable bleed valve assemblies. Each variable bleed valve assembly includes a variable bleed valve door that is selectively adjustable through a range of intermediate positions between a closed position and an open position. The variable bleed valve door is configured to maintain any of the intermediate positions. Each variable bleed valve assembly also includes an actuator operatively coupled to the variable bleed valve door. The actuator is configured to selectively adjust a position of the variable bleed valve door through the range of intermediate positions between the closed position and the open position.

An active clearance control system for a gas turbine engine includes an annular piston with a multiple of piston lift lugs. A method of active blade tip clearance control for a gas turbine engine includes translating axial movement of an annular piston to radial movement of a multiple of blade outer air seal segments.

A starter air valve (SAV) system includes a pressure actuated SAV actuator configured to be operatively connected to a SAV, a first pressure valve configured to selectively allow pressure from a pressure source to the SAV actuator when in fluid communication with the SAV actuator, and a second pressure valve configured to selectively allow pressure from the pressure source to the SAV actuator when in fluid communication with the SAV actuator. A manual override (MOR) valve selector is disposed between the first pressure valve, the second pressure valve, and the SAV actuator, the MOR valve selector configured to selectively fluidly connect the first pressure valve and the SAV actuator in a first position and to fluidly connect the second pressure valve and the SAV actuator in a second position.

An example flow control assembly includes a door that is moved to control flow through a heat exchanger, and a pneumatic device to move the door.

An actuator operable to drive a thrust reverser in a gas turbine engine, wherein the thrust reverser comprises first and second translatable sleeves. The actuator comprises a first actuating member moveable so as to translate the first sleeve and a second actuating member moveable so as to translate the second sleeve. The actuator further comprises an interlock arrangement operable in a locked mode in which the first actuating member and second actuating member are locked so as to move together and in an unlocked mode in which at least one of the first actuating member and second actuator member is free to move independently of the other. Operation of the actuator to open or close the thrust reverser comprises a first mode wherein the interlock arrangement is in the locked mode and a second mode wherein the interlock arrangement is in the unlocked mode.

A bleed air valve comprises a housing that includes an inlet, an outlet, and a center portion to selectively provide a pneumatic flow path between the inlet and the outlet. A piston moves along a center guide in response to forces applied to the piston, where the piston is spring biased to an open position. The valve also comprises a pressure regulator valve that comprises a spring loaded poppet valve that includes a pressure regulator inlet that receives an inlet pressure which is regulated based upon force applied to a pressure regulator piston. A valve spring applies a force to the piston first surface to spring bias the bleed air valve to the open position. A solenoid valve receives a command signal and in response provides compressed air to a solenoid valve outlet that is in fluid communication with the pressure regulator inlet.

An actuation system 100 comprises a fluid supply 130 that is fluidly connected to a position control actuator 110. The output of the position control actuator is determined by the fluid supply. The fluid supply is controlled by a piezoelectric actuator 150.

Methods and apparatus to control the actuation of regulators including a loading chamber are disclosed. An example apparatus includes a first pneumatic regulator including a loading chamber, the first pneumatic regulator to flow fluid toward a downstream process; a second pneumatic regulator coupled between the loading chamber and the downstream process, the second pneumatic regulator to control an actuation of the first pneumatic regulator during normal operation based on a pressure difference between a first pressure downstream of the first pneumatic regulator and a second pressure within the loading chamber; and a valve coupled between the loading chamber and the downstream process, the valve to control the actuation of the first pneumatic regulator during a shut-down event.