Abstract: A system for automatically restoring thrust to the working engine(s) of an aircraft if power is lost by an engine while the aircraft is operating at reduced thrust during a takeoff noise abatement maneuver is disclosed. The automatic thrust restoration (ATR) system is activated when: (1) the automatic throttle (A/T) system of the aircraft is engaged; (2) the throttle hold mode of operation of the A/T (which occurs during the initial takeoff period) has ended; and, (3) engine thrust is reduced below a preset value (which indicates that the aircraft is making a noise abatement maneuver). When these three conditions exist, the ATR system is activated for a period of time adequate for the aircraft to climb at a reduced slope to a prescribed altitude (e.g., 1500 feet). During the period of time the ATR system is activated, engine thrust is monitored. If thrust from an engine is lost, the ATR system automatically increases the throttle setting and, thus, the thrust of the working engine(s).

Abstract: The acceleration applied to an ejection seat during the catapult phase of emergency escape from an aircraft is limited to a maximum value which can be tolerated by the ejectee by incrementally venting exhaust gas from the high pressure chamber of the ejection catapult. Such venting may be accomplished mechanically by a mass which acts in response to acceleration to open venting orifices, the mass being preloaded to prevent its movement until a desired acceleration is experienced. Alternatively, venting may be accomplished electromechanically.

Abstract: A gas turbine engine has three turbines, the intermediate and high pressure turbines running at substantially constant corrected speed. The low pressure turbine has variable nozzle guide vanes and the low pressure compressor has variable stators so as to enable its speed to be varied, while its mass flow is arranged to be large at low speeds.

Abstract: A protective system is provided for water-jet propulsion systems in which water entering through an intake port is discharged in a jet by a pump. Unloading and overspeed of the pump prime mover may occur if the intake comes out of the water and this is prevented by a system which senses the water pressure in the pump inlet and responds to the pressure and the rate of change of pressure to prevent overspeed of the prime mover by setting it to idling speed. When the pressure and rate of change indicate that the intake is again submerged, the prime mover is reset to normal operating control.

Abstract: In order to detect effective operation of the reheat system of a turbo-jet ngine, a detection device is provided which is adapted to produce an output signal when such effective operation is sensed. The detection device includes means for sensing the pressure of the gas flow in the engine at a pair of preselected positions and feeding signals to processing means related to the pressures so sensed. When there is a preselected difference between the two signals, the output signal referred to above is generated.

Abstract: A rocket motor that has a main exhaust nozzle area and a secondary exhaust ozzle area with the secondary exhaust nozzle area being closed by burst discs that rupture and open secondary nozzle areas when predetermined temperatures and pressures are reached when propellant is burned inside the rocket motor.