A variable-section nozzle for an aircraft nacelle includes a deformable portion of which is movable between a narrow section position and a wide section position. In particular, the variable-section nozzle includes piezoelectric actuators and a controller to control the piezoelectric actuators in order to displace the deformable portion between the narrow and wide section positions. The piezoelectric actuators can be disposed on at least one faces of the deformable portion or be disposed end-to-end to form actuating rods.

A variable area nozzle assembly for a gas turbine engine includes a fixed structure including a first fixed ring and a second fixed ring. The second fixed ring is spaced axially aft from the first fixed ring to define a first portion of an ejector passage therebetween. A nozzle defines an inner radial exhaust flow path surface. The nozzle includes a forward ejector door and an aft ejector door. The forward ejector door and the aft ejector door define a first surface portion of the inner radial exhaust flow path surface. Each of the forward ejector door and the aft ejector door are pivotable between respective closed positions and respective open positions. A translating ejector sleeve is mounted within the fixed structure and configured to axially translate within the fixed structure between a first axial position and a second axial position.

An apparatus is provided for an aircraft propulsion system. This apparatus includes an exhaust nozzle. The exhaust nozzle includes a flowpath, a passage, an outer door, an inner door and an actuator configured to move the outer door and the inner door between an open arrangement and a closed arrangement. The flowpath extends axially along a centerline through the exhaust nozzle. The passage extends laterally into the exhaust nozzle to the flowpath when the outer door and the inner door are in the open arrangement. The outer door is configured to pivot inwards towards the centerline when the outer door moves from the closed arrangement to the open arrangement. The inner door is configured to pivot outwards away from the centerline when the inner door moves from the closed arrangement to the open arrangement.

The present disclosure relates to systems for controlling movement of a divergent flap (24) in an exhaust nozzle (20). A nozzle flap assembly may include a first link (42) pivotably coupled to a divergent flap (24). A second link (40) may be pivotably coupled to the first link and a static portion (44) of the exhaust nozzle. The second link may comprise a bumper (50). The first link may be configured to contact the bumper in response to the divergent flap being in a high thrust mode. The second link may be configured to contact the divergent flap in response to the divergent flap being in a low thrust mode.

A variable area fan nozzle comprises an actuator flap and a follower flap. The actuator flap has a portion in contact with a portion of the follower flap. A bias member biases the follower flap outwardly. An actuator actuates the actuator flap inwardly and outwardly to, in turn, move the follower flap against the bias member and to vary an area of an exhaust nozzle. The flap actuator is operable to drive the actuator flap out of contact with the follower flap into a thrust reverser position.

A variable area nozzle assembly for a gas turbine engine includes a nozzle disposed about a nozzle centerline and a fixed ring radially surrounding the nozzle. The nozzle includes a radially outer surface and a radially inner surface. The radially inner surface defines an outlet cross-sectional area of the nozzle. The nozzle is movable relative to the nozzle centerline between a first position of the radially inner surface defining a maximum area of the outlet cross-sectional area and a second position of the radially inner surface defining a minimum area of the outlet cross-sectional area. With the nozzle in the first position, the radially outer surface contacts the fixed ring. With the nozzle in the second position, the radially outer surface is spaced from the fixed ring.

A control system for a variable area fan nozzle (VAFN) is disclosed. The VAFN may have a plurality of petals and may be for use with a gas turbine engine. The control system may include a primary system configured to acquire primary data indicative of an operating condition of the VAFN, a secondary system configured to acquire secondary data indicative of a current operating condition of the gas turbine engine, and a control module in operative communication with the primary system and the secondary system. The control module may be configured to: determine a nozzle area of the VAFN based at least in part on the primary data, adjust the determined nozzle area based on the secondary data, and position the plurality of petals according to the adjusted nozzle area.

A control system for a variable area fan nozzle (VAFN) is disclosed. The VAFN may have a plurality of petals and may be for use with a gas turbine engine. The control system may include a primary system configured to acquire primary data indicative of an operating condition of the VAFN, a secondary system configured to acquire secondary data indicative of a current operating condition of the gas turbine engine, and a control module in operative communication with the primary system and the secondary system. The control module may be configured to: determine a nozzle area of the VAFN based at least in part on the primary data, adjust the determined nozzle area based on the secondary data, and position the plurality of petals according to the adjusted nozzle area.

Seals for gimbaling and/or fixed rocket engine nozzles, and associated systems and methods are disclosed. A representative rocket propulsion system includes a rocket engine having an exhaust nozzle, a seal plate carried by the exhaust nozzle, and a seal engaged with the seal plate. The seal includes at least one support, multiple pivotable first flaps, carried by the at least one support and positioned to contact the seal plate, and multiple pivotable second flaps, with an individual second flap positioned to shield a corresponding individual first flap. At least one forcing element is operatively coupled to at least one of the individual first flap or the individual second flap, to apply a pivoting force to the at least one of the individual first flap or the individual second flap.

Seals for gimbaling and/or fixed rocket engine nozzles, and associated systems and methods are disclosed. A representative rocket propulsion system includes a rocket engine having an exhaust nozzle, a seal plate carried by the exhaust nozzle, and a seal engaged with the seal plate. The seal includes at least one support, multiple pivotable first flaps, carried by the at least one support and positioned to contact the seal plate, and multiple pivotable second flaps, with an individual second flap positioned to shield a corresponding individual first flap. At least one forcing element is operatively coupled to at least one of the individual first flap or the individual second flap, to apply a pivoting force to the at least one of the individual first flap or the individual second flap.