A control system for a variable area fan nozzle (VAFN) having a plurality of petals is disclosed. The control system may include at least one fiber optic shape sensor extending along at least one of the plurality of petals, and a light source operatively connected to the at least one fiber optic shape sensor. The control system may further include a receiver operatively connected to the at least one fiber optic shape sensor. The control system may further include a VAFN control unit in operative communication with the plurality of petals and the receiver. The VAFN control unit may be configured to receive a signal from the receiver indicative of the measured strain along the at least one fiber optic shape sensor, and calculate a nozzle area of the VAFN based on the measured strain.

An engine fuel control system includes a fuel metering valve operable to control the flow of fuel between a supply line and a delivery line. The delivery line is configured to receive fuel from one or more fuel pumps. The engine fuel control system further includes a pressure raising arrangement which receives the fuel flow from the delivery line and raises the fuel pressure therein. The engine fuel control system further includes a pressure sensor arranged to sense the pressure of the fuel in the supply line between the one or more fuel pumps and the fuel metering valve, or to sense the pressure of the fuel in the delivery line between the fuel metering valve and the pressure raising arrangement.

An actuator system for actuating a movable structure of a thrust reverser, the system including a first motor, a first actuator driven by the first motor, a second actuator, and a first transmission shaft that is connected to the second actuator and to the first motor so that the second actuator is driven by the first motor, a second motor, a third actuator driven by the second motor, a fourth actuator, and a second transmission shaft that is connected to the fourth actuator and to the second motor so that the fourth actuator is driven by the second motor, and control means for controlling the motors to cause the first actuator, the second actuator, the third actuator, and the fourth actuator to be driven synchronously by the two motors. The invention also relates to a thrust reverser and to a jet engine fitted with such an actuator system.

A system for protecting the structural integrity of an engine strut may include a first monitor, a second monitor, and a controller communicatively coupled to the first monitor and the second monitor. The first monitor may be mounted proximate an engine strut coupling a turbine engine to an airframe of an aircraft. The second monitor may be mounted proximate the first monitor. The first monitor and the second monitor may each be configured to fail upon reaching a triggering temperature indicative of a burn-through in an engine case during operation of the turbine engine. The controller may be configured to automatically reduce an operating parameter of the turbine engine upon a failure of both the first monitor and the second monitor.

A gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a control unit to command the gas turbine engine to perform one of a rolling takeoff procedure and an unrestricted takeoff procedure. The control unit is configured command the gas turbine engine to perform the rolling takeoff procedure when information required to determine whether the unrestricted takeoff procedure can be performed is unavailable to the control unit.

A rocket engine having a co-axial, bidirectional flow arrangement is described herein. The rocket engine receives fuel and an oxidizer into the rocket engine in a first direction, whereby a portion of the fuel is combusted in a pre-burner. The flow direction of the partially combusted fuel/oxidizer mixture is reversed, whereby the mixture is introduced into a combustion chamber. The fuel and oxidizer are combusted in the combustion chamber. The combustion products exit a throat and an expansion plenum in a direction similar to the first direction, whereby the combustion products exit a nozzle of the rocket engine, providing thrust.

Various implementations of an extinguishable, solid propellant divert system for a flight vehicle are disclosed. Also disclosed are methods for using the divert system to control the flight of a flight vehicle. In one implementation, a divert system includes a hot gas generator pneumatically linked to one or more divert thrusters and an extinguishment valve. The extinguishment valve can be opened to rapidly depressurize the hot gas generator and extinguish the solid propellant burning inside. In another implementation, a method of controlling the trajectory of the flight vehicle includes repeatedly igniting and extinguishing the solid propellant in a hot gas generator and using the hot gas to provide divert thrust for the flight vehicle.

A bullnose ramp is disclosed. In various embodiments, the bullnose ramp includes a forward portion, the forward portion characterized by a first profile; an aft portion, the aft portion characterized by a second profile; and a transition portion positioned proximate an intersection between the forward portion and the aft portion, the transition portion defining a change in slope between the first profile and the second profile.

A turbofan gas turbine engine includes a fan section having a fan, a compressor section including a low pressure compressor and a high pressure compressor, a geared architecture including an epicyclic gear train, a turbine section including a low pressure turbine and a high pressure turbine, the fan driven by the low pressure turbine through the geared architecture, and a power density between 4.84 lbf/in.sup.3 and 5.5 lbf/in.sup.3.

A thrust reverser actuation system includes a first cowl actuation system for translating a first cowl of a thrust reverser and a second, separate cowl actuation system for translating a second cowl of the thrust reverser. The system also includes a device operatively connected between the first cowl actuation system and the second cowl actuation system, and configured to transmit drive from one of the first and second cowl actuation systems to the other of the first and second cowl actuation systems in the event of a failure of the other of the first and second cowl actuation systems.