Abstract: A gas turbine engine includes a fan and an engine core that includes a compressor, a combustor, and a turbine. The fan and the compressor include variable pitch geometry. The gas turbine engine further includes a control system configured to adjust the variable pitch geometry of the fan and the compressor to optimize a performance characteristic of the gas turbine engine.

Abstract: System and methods are provided that use a recharge device to resupply a reservoir and tank with fluids used to power a turbine, which in turn powers a generator, wherein one of the resupplied fluids is used to cool a load that is powered by the generator.

Abstract: A start system for an expendable gas turbine engine is provided. The start system may include: a tank configured to store a pressurized gas comprising oxygen; a non-pyrotechnic igniter in communication with a combustion chamber of the expendable gas turbine engine; a starter tube configured to feed the pressurized gas from the tank into the combustion chamber; and a valve configured to regulate a flow of the pressurized gas from the tank into the starter tube; wherein, the start system is configured to startup the expendable gas turbine engine by the flow of the pressurized gas from the tank, through the valve and the starter tube, into the combustion chamber and, from the combustion chamber, into a plurality of turbine blades of the expendable gas turbine engine, and by ignition, by the non-pyrotechnic igniter, of fuel injected into the combustion chamber.

Abstract: Systems and methods are provided that use compressed gas to power a turbine, which in turn powers a generator, where an expansion of the compressed gas provides cooling for an electrical load that is powered by the generator.

Abstract: A container may be supplied with an incompressible fluid. For example, the container may be partially or completely prefilled with the incompressible fluid. The container may be supplied with a flow of compressible gas via a first valve. The first valve may regulate the flow of the compressible gas supplied to the container based on a pressure setting of the first valve. A second valve may release the incompressible fluid from the container as the container is filled with the compressible gas and in response to a pressure of the container being greater than a pressure setting of the second valve. The pressure setting of the first valve may be greater than the pressure setting of the second valve.

Abstract: Systems and methods of augmenting the thrust of the prime power engine(s) of an aircraft from a tank of compressed gas are described herein.

Abstract: Systems and methods are provided that use compressed gas from a tank in an aircraft to avoid and/or recover from a compressor surge. Systems and methods are provided that use compressed gas from a tank to startup a gas turbine engine in an aircraft, where the gas turbine engine is configured as a prime power engine for the aircraft.

Abstract: A gas turbine engine includes a fan and an engine core that includes a compressor, a combustor, and a turbine. The fan and the compressor include variable pitch geometry. The gas turbine engine further includes a control system configured to adjust the variable pitch geometry of the fan and the compressor to optimize a performance characteristic of the gas turbine engine.

Abstract: Systems and methods are provided that use compressed gas to power a turbine, which in turn powers a generator, where an expansion of the compressed gas provides cooling for an electrical load that is powered by the generator.

Abstract: A container may be supplied with an incompressible fluid. For example, the container may be partially or completely prefilled with the incompressible fluid. The container may be supplied with a flow of compressible gas via a first valve. The first valve may regulate the flow of the compressible gas supplied to the container based on a pressure setting of the first valve. A second valve may release the incompressible fluid from the container as the container is filled with the compressible gas and in response to a pressure of the container being greater than a pressure setting of the second valve. The pressure setting of the first valve may be greater than the pressure setting of the second valve.

Abstract: Systems and methods of augmenting the thrust of the prime power engine(s) of an aircraft from a tank of compressed gas are described herein.

Abstract: An ultra high bypass ratio turbofan engine includes a variable pitch fan, a low pressure turbine, a reduction gearbox, and a plurality of outlet guide vanes. The ultra high bypass ratio turbofan engine has a bypass ratio between about 18 and about 40. The variable pitch fan and the low pressure turbine are coupled together by the reduction gearbox. The reduction gearbox reduces the speed of the variable pitch fan relative to the low pressure turbine. The plurality of outlet guide vanes are spaced aft of the variable pitch fan and are axially swept. The variable pitch fan and the low pressure turbine are configured to generate a fan pressure ratio between about 1.15 and about 1.24.