Abstract: A hybrid electric propulsion system including: a gas turbine engine comprising a low speed spool, a high speed spool, and a combustor; a lubrication circuit comprising a bearing compartment, a supply pump, and a scavenger pump; an electric motor configured to augment rotational power of the low speed spool or the high speed spool; and a controller operable to: control the electric motor based upon a pressure differential between an interior of the bearing compartment and an exterior of the bearing compartment and to drive rotation of the low speed spool and/or the high speed spool via the electric motor responsive to a thrust command while fuel flow to the combustor is inhibited.

Abstract: A hybrid electric propulsion system including: a gas turbine engine comprising a low speed spool, a high speed spool, and a combustor; a lubrication circuit comprising a bearing compartment, a supply pump, and a scavenger pump; an electric motor configured to augment rotational power of the low speed spool or the high speed spool; and a controller operable to: control the electric motor based upon a pressure differential between an interior of the bearing compartment and an exterior of the bearing compartment and to drive rotation of the low speed spool and/or the high speed spool via the electric motor responsive to a thrust command while fuel flow to the combustor is inhibited.

Abstract: A hybrid electric propulsion system including: a gas turbine engine comprising a low speed spool, a high speed spool, and a combustor; a lubrication circuit comprising a bearing compartment, a supply pump, and a scavenger pump; an electric motor configured to augment rotational power of the low speed spool or the high speed spool; and a controller operable to: control the electric motor based upon a pressure differential between an interior of the bearing compartment and an exterior of the bearing compartment and to drive rotation of the low speed spool and/or the high speed spool via the electric motor responsive to a thrust command while fuel flow to the combustor is inhibited.

Abstract: A fluid pulse device includes a piezo actuated valve, a piezo injector, a delivery system, and a control system. The piezo actuated valve has a valve body, a tube, and a piston assembly. The valve body defines a first opening, a second opening, and a valve cavity that is disposed between the first opening and the second opening. The tube extends from the valve body. The piston assembly includes a piston head and a stem that is connected to the piston head. The piezo injector has an injector tip that extends through the first opening. The delivery system is fluidly connected to the piezo injector. The control system is operatively connected to the piezo injector and is configured to actuate the piezo injector to provide a fluid pulse.

Abstract: A fluid pulse device includes a piezo actuated valve, a piezo injector, a delivery system, and a control system. The piezo actuated valve has a valve body, a tube, and a piston assembly. The valve body defines a first opening, a second opening, and a valve cavity that is disposed between the first opening and the second opening. The tube extends from the valve body. The piston assembly includes a piston head and a stem that is connected to the piston head. The piezo injector has an injector tip that extends through the first opening. The delivery system is fluidly connected to the piezo injector. The control system is operatively connected to the piezo injector and is configured to actuate the piezo injector to provide a fluid pulse.

Abstract: A gas turbine engine system includes an airframe support, a gas turbine engine mounted to the airframe support, a nozzle exhaust mounted to the airframe support, and a flexible annular seal having a first end that is attached to the gas turbine engine and a second end that is attached to an exhaust nozzle. The flexible annular seal may include a flexible annular wall that permits relative deflection between the gas turbine engine and the exhaust nozzle to facilitate the reduction of undesirable load transfer.

Abstract: A system includes a gas turbine engine, a nozzle structure located adjacent to the gas turbine engine, a flexible annular seal linking the gas turbine engine and the nozzle structure, the flexible annular seal having a plurality of corrugate sections, and a reinforcement member positioned between two of the plurality of corrugate sections.

Abstract: A system includes a gas turbine engine, a nozzle structure located adjacent to the gas turbine engine, a flexible annular seal linking the gas turbine engine and the nozzle structure, the flexible annular seal having a plurality of corrugate sections arranged about a centerline, and a connection device secured to the gas turbine engine and to the nozzle structure. The connection device is adjustable to select a length of the flexible annular seal measured along the centerline.

Abstract: A system includes a gas turbine engine, a nozzle structure located adjacent to the gas turbine engine, a flexible annular seal linking the gas turbine engine and the nozzle structure, the flexible annular seal having a plurality of corrugate sections arranged about a centerline, and a connection device secured to the gas turbine engine and to the nozzle structure. The connection device is adjustable to select a length of the flexible annular seal measured along the centerline.

Abstract: A system includes a gas turbine engine, a nozzle structure located adjacent to the gas turbine engine, a flexible annular seal linking the gas turbine engine and the nozzle structure, the flexible annular seal having a plurality of corrugate sections, and a reinforcement member positioned between two of the plurality of corrugate sections.

Abstract: A composite engine case with an axial interface. One configuration includes an alternating mix of full length and partial plies, in order to provide the total thickness needed for the axial overlap. Another configuration provides only full-length structural plies with a flyaway insert adjacent the axial interface.

Abstract: A gas turbine engine system includes an airframe support, a gas turbine engine mounted to the airframe support, a nozzle exhaust mounted to the airframe support, and a flexible annular seal having a first end that is attached to the gas turbine engine and a second end that is attached to an exhaust nozzle. The flexible annular seal may include a flexible annular wall that permits relative deflection between the gas turbine engine and the exhaust nozzle to facilitate the reduction of undesirable load transfer.

Abstract: A composite engine case with an axial interface. One configuration includes an alternating mix of full length and partial plies, in order to provide the total thickness needed for the axial overlap. Another configuration provides only full-length structural plies with a flyaway insert adjacent the axial interface.