Methods and systems for operating oxidizer systems

An oxidizer supply system for an aircraft having a propulsion engine, said oxidizer supply system comprising:

• an air collection and enrichment system configured to generate liquid oxygen;
• and
• a gas turbine engine configured to be non-propulsive and configured to operate using ambient air during proper operation of the propulsion engine, said gas turbine engine comprising:
• a combustor;
• a low pressure compressor configured to compress ambient air and discharge a flow of compressed air;
• a high pressure compressor coupled downstream from and in flow communication with said low pressure compressor, said high pressure compressor configured to further compress the flow of compressed air and discharge a first portion of the further compressed air to said air collection and enrichment system, said high pressure compressor further configured to discharge a second portion of the further compressed air to said combustor;
• and
• a turbine coupled in flow communication with said air collection and enrichment system, said air collection and enrichment system configured to discharge a flow of air to said turbine.

A gas turbine engine for use on an aircraft having a propulsion engine, said gas turbine engine configured to be non-propulsive and configured to be coupled in flow communication with an air collection and enrichment system for generating liquid oxygen, wherein said gas turbine engine is configured to operate using ambient air during proper operation of the propulsion engine, said gas turbine engine comprising:

• a combustor;
• a compressor upstream of said combustor, said compressor configured to receive and compress ambient air for discharge to the air collection and enrichment system;
• and
• a turbine downstream of said combustor, at least one of said combustor and said turbine configured to receive a flow of oxygen-depleted air from the air collection and enrichment system.