A face seal assembly includes a seal carrier, a seal element supported by the seal carrier, a rotating seal plate interactive with the seal element to define a face seal, and a seal arrester configured to engage the seal carrier at a predetermined amount of wear of the seal element to stop wear of the seal element.

A gas turbine engine may include a rotor overspeed protection (ROP) assembly. The ROP assembly may include an annular blade outer air seal (BOAS) assembly including a ROP segment. The ROP assembly may include a stator vane coupled with the BOAS assembly/. The stator vane may include a stator flange disposed about a forward edge portion of the stator vane. The ROP segment may include a ROP flange extending in an axially aft direction from a main body of the ROP segment toward the stator vane, wherein the ROP flange is disposed radially inward of the stator flange.

The invention regards a gas turbine engine control system and a method for limiting turbine overspeed in case of a shaft failure. The control system includes: an overspeed protection system that activates an activation member in case a shaft failure is detected; a fuel limiting mechanism coupled with the activation member, wherein the fuel limiting mechanism is configured to limit the fuel supply to the gas turbine engine combustor if the activation member is activated; a variable stator vane mechanism which is configured to adjust variable stator vanes of a compressor of the gas turbine engine in their rotational position, the variable stator vanes having a closed position which blocks air flow through the compressor. A connecting fuel line connecting the fuel limiting mechanism and the variable stator vane mechanism is provided, wherein upon activation of the activation member the fuel limiting mechanism pressurizes the connecting fuel line, thereby activating the variable stator vane mechanism to move at least one row of the variable stator vanes into the closed position.

A propulsion assembly with an outer compartment, an inner compartment, a supply pipe and a transfer pipe between the two compartments, a suction system between the two pipes, a regulating element that regulates the flow rate of air in the suction system and a fire-fighting system having a reservoir of extinguishing fluid, a discharge pipe connected to the reservoir, and a control system between the reservoir and the discharge pipe. The discharge pipe is configured and arranged to supply the transfer pipe when the control system is in the open position. The outside air is then driven by the suction system and passes through the two compartments in a forced manner and the extinguishing fluid reaches the transfer pipe to flow into the inner compartment.

A system includes a first AC bus configured to supply power from a first AC power source. A second AC bus is configured to supply power from a second AC power source. A first transformer rectifier unit (TRU) connects a first DC bus to the first AC bus through a first TRU contactor (TRUC). A second TRU connects a second DC bus to the second AC bus through a second TRUC. A first voltage sensor is connected to sense voltage of the first DC bus. A second voltage sensor is connected to sense voltage of the second DC bus. A ram air turbine (RAT) automatic deployment controller is operatively connected to the first voltage sensor and to the second voltage sensor to automatically deploy a RAT based on the combined status of the first voltage sensor and the second voltage sensor.

A sensor signal produced by a sensor as a feedback device rotates with a propeller about an axis and moves along the axis with adjustment of a blade angle of the propeller is received, the sensor signal indicative of a rotational speed and of the blade angle of the propeller. From the sensor signal, it is determined whether the rotational speed is within a predetermined range of a reference speed and an expected change in the blade angle has occurred in response to a command to adjust the blade angle to maintain the rotational speed at the reference speed. In response to determining that the rotational speed is within the predetermined range of the reference speed and the expected change in the blade angle has failed to occur in response to the command, inoperable movement of the feedback device along the axis is determined and an alert is output.

In one embodiment, a plant control apparatus includes a first stop controller configured to, when stopping a plant, stop a steam turbine to start to drop rotating speed of a second shaft of the steam turbine from rated speed, and start to drop rotating speed of a first shaft of a gas turbine from the rated speed while continuing combustion of a combustor after the stop of the steam turbine. The apparatus further includes a second stop controller configured to shut off fuel of the combustor to stop the gas turbine when the rotating speed of the first shaft drops to first speed. The second stop controller stops the gas turbine such that the rotating speed of the first shaft catches up with the rotating speed of the second shaft at second speed that is equal to or lower than the first speed and a clutch is engaged.

A failure detection method and system for a propeller control unit coupled to a propeller are provided. An actual value of a blade angle and/or a rotational speed of the propeller are obtained. A comparison between the actual value and a threshold is performed. In response to determining, based on the comparison, that the actual value exceeds the threshold, the propeller control unit is caused to adjust the blade angle to bring the blade angle and/or the rotational speed towards the threshold. A subsequent actual value of the blade angle and/or the rotational speed is obtained. From the subsequent value, it is determined whether the blade angle and/or the rotational speed has been brought towards the threshold. In response to determining that the blade angle and/or the rotational speed has failed to be brought towards the threshold, failure of the propeller control unit is detected and an alert is output.

Methods and systems for fault detection of a fuel control unit of an engine are provided. Exceedance of at least one engine parameter beyond a safety threshold, associated with excessive fuel flow to the engine, is detected at an engine controller associated with the engine. The fuel control unit is commanded, via the engine controller, to implement a reduction in the fuel flow to the engine. Following the commanding of the fuel control unit, subsequent exceedance of the at least one engine parameter beyond the safety threshold is detected at the engine controller. A fault of the fuel control unit is determined at the engine controller, based on the subsequent exceedance. In response to determining the fault of the fuel control unit, at least one countermeasure to the fault of the fuel control unit is triggered by the engine controller.

A gas turbine engine includes an electrical machine positioned at least partially inward of a core airflow path, the electrical machine including an electrical rotor component and an electrical stator component, a connecting member positioned between the electrical machine and a rotary member, a disconnection device that is positionable between a disengaged position, in which the disconnection device is disengaged from the connecting member, and an engaged position, in which the disconnection device is engaged with the connecting member, and a controller including a processor, where the processor receives a signal from the electrical machine indicative of a fault, and in response to receiving the signal from the electrical machine indicative of the fault, directs the disconnection device to move from the disengaged position to the engaged position.