In accordance with at least one aspect of this disclosure, there is provided a system for an aircraft engine. In embodiments, the system includes an accessory box and a fuel accessory located in an interior space within the accessory box, where a vent is defined through a wall of the accessory box. In embodiments, the vent includes a plurality of holes or slots in an outer wall of the accessory box for passage of gaseous fuel from the interior space. In embodiments, the vent is configured for passive ventilation of the interior space.

A method is provided during which an aircraft powerplant is provided. The aircraft powerplant includes a combustor and a water recovery system. The water recovery system includes a condenser and a reservoir. Fuel is combusted within the combustor to provide combustion products. Water is extracted from the combustion products using the condenser. The water recovery system is operated in one of a plurality of modes based on likelihood of contrail formation. The modes include a first mode and a second mode, where the water is collected within the reservoir during the first mode, and where the water passes through the water recovery system during the second mode.

An articulating exhaust nozzle thrust reverser includes an outer articulating panel comprising an outer skin and an outer thrust reverser door and an inner articulating panel comprising a forward inner skin, an aft inner skin, and an inner thrust reverser door. The outer articulating panel is configured to pivot to vary a nozzle exit area. The forward inner skin is configured to pivot to vary a nozzle throat area. The outer thrust reverser door is pivotally coupled to the outer skin. The inner thrust reverser door is pivotally coupled to the aft inner skin. The outer articulating panel and the inner articulating panel may be individually operated to independently vary the exhaust nozzle throat area and/or the exhaust nozzle exit area.

An articulating exhaust nozzle thrust reverser includes an outer articulating panel comprising an outer skin and an outer thrust reverser door and an inner articulating panel comprising a forward inner skin, an aft inner skin, and an inner thrust reverser door. The outer articulating panel is configured to pivot to vary a nozzle exit area. The forward inner skin is configured to pivot to vary a nozzle throat area. The outer thrust reverser door is pivotally coupled to the outer skin. The inner thrust reverser door is pivotally coupled to the aft inner skin. The outer articulating panel and the inner articulating panel may be individually operated to independently vary the exhaust nozzle throat area and/or the exhaust nozzle exit area.

A system includes an air chamber and an oil capture cavity. The air chamber includes an inlet to receive pressurized air from a gas turbine engine. The oil capture cavity is positioned between the air chamber and an oil sump supplying lubricating oil to the gas turbine engine. The oil capture cavity includes an auxiliary vent formed in a base of the oil capture cavity. A seal may separate the oil capture cavity from fluid communication with the oil sump. A nozzle provides fluid communication between the oil capture cavity and the air chamber. The nozzle is configured and positioned to direct a stream of the pressurized air into the oil capture cavity against an opposite wall of the oil capture cavity to create a quiescent zone at the base of the oil capture cavity. The quiescent zone includes the auxiliary vent.

A system includes an air chamber and an oil capture cavity. The air chamber includes an inlet to receive pressurized air from a gas turbine engine. The oil capture cavity is positioned between the air chamber and an oil sump supplying lubricating oil to the gas turbine engine. The oil capture cavity includes an auxiliary vent formed in a base of the oil capture cavity. A seal may separate the oil capture cavity from fluid communication with the oil sump. A nozzle provides fluid communication between the oil capture cavity and the air chamber. The nozzle is configured and positioned to direct a stream of the pressurized air into the oil capture cavity against an opposite wall of the oil capture cavity to create a quiescent zone at the base of the oil capture cavity. The quiescent zone includes the auxiliary vent.

A hydrogen fuel system including a fuel delivery assembly, a purge gas source, and a vent. The fuel delivery assembly is configured to receive hydrogen fuel from a hydrogen fuel source and to provide the hydrogen fuel from the hydrogen fuel source to a power generator. The purge gas source is fluidly coupled to the fuel delivery assembly and configured to provide a purge gas to the fuel delivery assembly. The vent is fluidly coupled to the fuel delivery assembly and configured to vent hydrogen fuel from the fuel delivery assembly when the purge gas is provided to the fuel delivery assembly.

A propulsion system includes two gas turbine engines and an air-provisioning system. The air-provisioning system includes a first ejector, a second ejector, a plenum fluidically connected with the first ejector and the second ejector, and a first propulsor. The air-provisioning system is configured to bleed and mix air from each gas turbine engine in the ejectors so as to provide selectively a flow of plenum air from the plenum to the first propulsor at a desired pressure and a desired flow rate to power the first propulsor.

A ducted fan turbine engine with a nacelle and a duct for a secondary flow. The nacelle comprises a fixed structure. A mobile cowl is able to move between a forward position and a backward position to define an opening between the duct and the outside. A plurality of rollers are mounted to freely rotate on the mobile cowl. For each roller there is a flexible screen with a first edge fixed to the roller and a second edge, in which the screen is able to adopt a furled position, wound around the roller, or a deployed position deployed across the duct. A deployment mechanism is arranged to move each second edge to move the screen from the furled position to the deployed position. A furling mechanism is arranged to drive each roller in rotation to move the associated screen from the deployed position to the furled position.

Cooling a torque probe involves an elongated sleeve extending along a sleeve axis between a first sleeve end and a second sleeve end. The sleeve is mountable about the torque probe to define a flow passage between an inner surface of the sleeve and an outer surface of the torque probe. The flow passage is in fluid communication with a flow passage inlet of the sleeve and with a flow passage outlet of the sleeve spaced apart along the sleeve axis from the flow passage inlet. A cooling airflow is configured to flow into the flow passage via the flow passage inlet, through the flow passage along the outer surface of the torque probe to cool the torque probe, and out of the flow passage via the flow passage outlet.