An engine-driven cryogenic cooling system for an aircraft includes a first air cycle machine, a second air cycle machine, and a means for condensing a chilled air stream into liquid air for an aircraft use. The first air cycle machine includes a plurality of components operably coupled to a gearbox of a gas turbine engine and configured to produce a cooling air stream based on a first engine bleed source of the gas turbine engine. The second air cycle machine is operable to output the chilled air stream at a cryogenic temperature based on a second engine bleed source cooled by the cooling air stream of the first air cycle machine.

A cryogenic cooling system for an aircraft includes a first air cycle machine, a second air cycle machine, and a means for collecting liquid air. The first air cycle machine is operable to output a cooling air stream based on a first air source. The second air cycle machine is operable to output a chilled air stream at a cryogenic temperature based on a second air source cooled by the cooling air stream of the first air cycle machine. An output of the second air cycle machine is provided to the means for collecting liquid air.

A ground-based cryogenic cooling system includes a means for cooling an airflow and producing chilled air responsive to a power supply. A liquid air condensate pump system is operable to condense the chilled air into liquid air and urge the liquid air through a feeder line. A cryogenic cartridge includes a coupling interface configured to detachably establish fluid communication with the feeder line and a cryogenic liquid reservoir configured to store the liquid air under pressure. The cryogenic cartridge can be coupled to a cryogenic liquid distribution system on an aircraft. The liquid air can be selectively released from the cryogenic cartridge through the cryogenic liquid distribution system for an aircraft use.

A system for an aircraft includes an engine bleed source of a gas turbine engine. The system also includes a means for chilling an engine bleed air flow from the engine bleed source to produce a chilled working fluid. The system further includes a means for providing the chilled working fluid for an aircraft use.

A propulsion system includes an electric fan propulsion motor with a plurality of propulsion motor windings. The propulsion system also includes a means for controlling a flow rate of a working fluid through a cryogenic working fluid flow control assembly to the propulsion motor windings. The propulsion system further includes a controller operable to control supplying a pre-cooling flow of the working fluid from a cryogenic liquid reservoir through the cryogenic working fluid flow control assembly to the propulsion motor windings.

A system for an aircraft includes an engine bleed source of a gas turbine engine. The system also includes a means for chilling an engine bleed air flow from the engine bleed source to produce a chilled working fluid. The system further includes a means for providing the chilled working fluid for an aircraft use.

The method for producing liquid hydrogen can include the steps of: introducing pressurized natural gas from a high pressure natural gas pipeline to a gas processing unit under conditions effective for producing a purified hydrogen stream; and introducing the purified hydrogen stream to a hydrogen liquefaction unit under conditions effective to produce a liquid hydrogen stream, wherein the hydrogen liquefaction unit provides a warm temperature cooling and a cold temperature cooling to the purified hydrogen stream, wherein the warm temperature cooling is provided by utilizing letdown energy of a pressurized stream selected from the group consisting of a nitrogen stream sourced from a nitrogen pipeline, a natural gas stream sourced from the high pressure natural gas pipeline, an air gas sourced from an air separation unit, and combinations thereof, wherein the cold temperature is provided by utilizing letdown energy of the purified hydrogen stream.

A cryogenic cooling system for an aircraft includes a first air cycle machine, a second air cycle machine, and a means for collecting liquid air. The first air cycle machine is operable to output a cooling air stream based on a first air source. The second air cycle machine is operable to output a chilled air stream at a cryogenic temperature based on a second air source cooled by the cooling air stream of the first air cycle machine. An output of the second air cycle machine is provided to the means for collecting liquid air.

A system for an aircraft includes an engine bleed source of a gas turbine engine. The system also includes a means for chilling an engine bleed air flow from the engine bleed source to produce a chilled working fluid. The system further includes a means for providing the chilled working fluid for an aircraft use.

A propulsion system includes an electric fan propulsion motor with a plurality of propulsion motor windings. The propulsion system also includes a means for controlling a flow rate of a working fluid through a cryogenic working fluid flow control assembly to the propulsion motor windings.