Abstract: A piston ring for use at temperatures above 350° F. at pressures greater than or equal to about 2000 psi, comprising a gap having a gap width about 1.4 to about 2.0 times greater than a thickness of the piston ring; a height about 4.5 to about 6.4 times larger than the thickness, and a leading edge characterized by an arc having a radius of curvature of less than or equal to about 4 times the height. The piston ring may be formed of a material comprising cobalt, chromium, tungsten, and carbon. A gas compressor and method of sealing a piston using the above piston ring is also provided for.

Abstract: A closed cycle turbine system is provided for the generation of power in a light, high altitude airborne vehicle. The closed cycle turbine system may operate according to either the Brayton or the Rankine cycles. The working fluid for the closed cycle may be alternately heated by the combination of an external burner and heat exchanger and cooled by expansion and radiation. The use of the external burner operating at near the atmospheric pressure may eliminate the requirement for a compressor to compress large amounts of low density, ambient air for use in the turbine. Additional ambient air may be provided to the burner by either using a fan to concentrate the ambient air or pressurizing the fuel stream so as to entrain the ambient air therein. The external burner may use a gaseous fuel such as hydrogen or liquid fuel such as jet fuel to provide heat for the closed cycle.

Abstract: A coalescing assembly for coalescing entrained oil from a high temperature, high velocity gas stream comprises a coalescing element of compacted high temperature polyamide fibers, such as those available under the trademark Nomex®, rigidly held by concentric cylindrical support structures of a dense fibrous material such as stainless steel. The coalescing assembly forms a component of an oil coalescer having a unique hole configuration in its outer shell to prevent coalesced oil from being re-entrained into the gas stream. The oil coalescer is a component of an oil separator for use in aircraft operational environments and features high durability and longevity of 10 years or more.

Abstract: An emergency power system comprising a plurality of solid propellant gas generators each having a gas outlet in fluid communication with a turbine wheel rotationally disposed within a gas turbine housing, the turbine wheel being in rotational communication with an electric generator input shaft, a fluid pump input shaft, or both. A method of producing power from such an emergency power system is also disclosed.

Abstract: A closed cycle turbine system is provided for the generation of power in a light, high altitude airborne vehicle. The closed cycle turbine system may operate according to either the Brayton or the Rankine cycles. The working fluid for the closed cycle may be alternately heated by the combination of an external burner and heat exchanger and cooled by expansion and radiation. The use of the external burner operating at near the atmospheric pressure may eliminate the requirement for a compressor to compress large amounts of low density, ambient air for use in the turbine. Additional ambient air may be provided to the burner by either using a fan to concentrate the ambient air or pressurizing the fuel stream so as to entrain the ambient air therein. The external burner may use a gaseous fuel such as hydrogen or liquid fuel such as jet fuel to provide heat for the closed cycle.

Abstract: A method to desorb water from a desiccant of an air recharge system comprises the steps of a) filling a purge reservoir using an air compressor and a desiccant dryer to produce discharge air, b) stopping the air compressor; c) back purging the desiccant, and d) vent resetting the system, wherein the filling a purge reservoir step does not result in an addition of discharge air to an air storage tank in fluid communication with the purge reservoir and wherein the air storage tank is filled with an amount of the discharge air such that the air storage tank is at a full storage tank pressure prior to filling the purge reservoir. A method of filling an air storage tank of an air recharge system is also disclosed.

Abstract: A coalescing assembly for coalescing entrained oil from a high temperature, high velocity gas stream comprises a coalescing element of compacted high temperature polyamide fibers, such as those available under the trademark Nomex®, rigidly held by concentric cylindrical support structures of a dense fibrous material such as stainless steel. The coalescing assembly forms a component of an oil coalescer having a unique hole configuration in its outer shell to prevent coalesced oil from being re-entrained into the gas stream. The oil coalescer is a component of an oil separator for use in aircraft operational environments and features high durability and longevity of 10 years or more.

Abstract: An emergency power system comprising a plurality of solid propellant gas generators each having a gas outlet in fluid communication with a turbine wheel rotationally disposed within a gas turbine housing, the turbine wheel being in rotational communication with an electric generator input shaft, a fluid pump input shaft, or both. A method of producing power from such an emergency power system is also disclosed.

Abstract: A piston ring for use at temperatures above 350° F. at pressures greater than or equal to about 2000 psi, comprising a gap having a gap width about 1.4 to about 2.0 times greater than a thickness of the piston ring; a height about 4.5 to about 6.4 times larger than the thickness, and a leading edge characterized by an arc having a radius of curvature of less than or equal to about 4 times the height. The piston ring may be formed of a material comprising cobalt, chromium, tungsten, and carbon. A gas compressor and method of sealing a piston using the above piston ring is also provided for.