A gas turbine engine includes a core engine defined about an axis, a gear system driven by the core engine, a fan, and a variable area flow system. The gear system defines a gear reduction ratio of greater than or equal to about 2.3. The fan is driven by the gear system about the axis to generate a bypass flow. The variable area flow system operates to effect the bypass flow.

A turbine engine having an engine core, an inner cowl radially surrounding the engine core, an outer cowl radially surrounding the inner cowl and spaced from the inner cowl to form an annular passage between the inner and outer cowls that defines a nozzle, at least one control surface provided on the inner cowl and movable between a retracted position, where the nozzle has a first cross-sectional area, and an extended position where the nozzle has a second cross-sectional area that is less than the first cross-sectional area and an actuator operably coupled to the control surface and configured to move the control surface to control the cross-sectional area of the nozzle.

Systems and methods are provided that lock thrust reversers and also drive fan nozzles of an aircraft. One system includes a coupling configured to selectively engage and disengage. While engaged, the coupling is configured to rotate to drive a Variable Area Fan Nozzle (VAFN), at least a portion of which is on a translating portion of a thrust reverser of an aircraft. Furthermore, while engaged the coupling is configured to prevent displacement of the translating portion.

An exhaust nozzle for a gas turbine engine may include a plurality of flap trains in the exhaust stream of the gas turbine engine. The flap trains are operable to selectively control three separate flow paths of gas that traverse the engine. A first stream of is the core airflow. The second stream of air is peeled off of the first stream to form a low pressure fan bypass air stream. The third stream of air traverses along the engine casing and is passed over a flap assembly to aid in cooling. The flaps are operable converge/diverge to control the multiple streams of air.

An exemplary nozzle having a variable internal exhaust area for a gas turbine engine can have a plurality of flap trains extending around a periphery of the gas turbine engine. Each flap train can include a convergent flap pivotally attached to an engine body and a divergent flap pivotally attached to the engine body downstream of the convergent flap. The nozzle can further have a fluid circuit in communication with the convergent and divergent flaps and configured to pivot the convergent and divergent flaps between a radially inward position and a radially outward position.

A thrust deflecting device for deflecting a thrust stream is disclosed, which includes a flap system having a plurality of deflecting flaps, each of which is pivotable around its yaw axis, the flap system being situated between parallel control surfaces such as baffle plates which, together with the flap system, form a box structure, which is pivotable around a pivot axis running in the direction of the transverse axis for the purpose of deflecting the thrust stream in the pitch direction, an aircraft engine also being disclosed.

A variable area fan nozzle comprising an array of rigid petals and a petal actuation system comprising left and right assemblies, each assembly comprising: a multiplicity of tracks attached to or integrally formed with respective petals; a curved pivoting ring segment; an actuator coupled to the ring segment; and a multiplicity of sets of cam followers spaced along the ring segment and aligned with respective tracks. Each ring segment is pivotable between first and second angular positions depending on how the state of the actuator changes. As one ring segment pivots in one direction, one set of cam followers exert inward forces on the tracks to deflect petals inward; as that ring segment pivots in the other direction, another set of cam followers exert outward forces on the tracks to deflect petals outward.

A nozzle assembly includes a sleeve defining a pathway, the sleeve disposed within a nacelle. The pathway and an internal surface of the nacelle guides a mass flow from an engine to an exit of the propulsion system. The sleeve is configured to move between a forward position an aft position within the nacelle aft of the engine. The sleeve has a protruding portion that extends towards a center of the pathway and that defines a smallest internal diameter of the sleeve. The sleeve includes a plurality of sleeve segments that are longitudinally aligned and circumferentially arranged to form the sleeve. The sleeve segments are configured to move circumferentially closer as the sleeve moves in a first direction within the nacelle and to move circumferentially further apart as the sleeve moves in a second direction within the nacelle. An actuator is coupled with, and is configured to move the sleeve.

Dual bypass gas turbine engines and associated methods are provides. A dual bypass turbofan gas turbine engine includes counter-rotating first and second fans through which ambient air is received and propelled in an aft direction; a first bypass duct receiving first bypass air including a first portion of the propelled air; a second bypass duct receiving second bypass air including a second portion of the propelled air; a core gas path receiving core air including a third portion of the propelled air; a compressor pressurizing the core air; an intercooler facilitating heat removal from the pressurized core air; a combustor in which the pressurized core air is mixed with fuel and ignited to generate a stream of combustion gas; a turbine extracting energy from the combustion gas; and a differential gear train apportioning an input torque received from the turbine between the first fan and the second fan.

A variable area fan nozzle comprising an array of hinged rigid petals and a petal actuation system in which the principle of actuation is realized by changes in shape (i.e., deformation) of the actuators rather than by movement of cooperating mechanical parts. Because these actuators have no rotating or sliding mechanical components, wear and associated maintenance are reduced. Each deformable actuator has a portion made of shape memory alloy that has been trained to change shape in a specific manner when heated to a temperature above a transition temperature. In addition, each shape memory alloy actuator is shaped to act as a fairing to reduce aerodynamic drag.