US Patent 6997970 Oxygen/inert gas generator

A gas generation method and apparatus, capable of use in an aircraft, generates oxygen with at least one On Board Oxygen Generating System (OBOGS) and generates an inert gas with at least one On Board Inert Gas Generating System (OBIGGS) and selectively supplies an auxiliary supply of inert gas utilizing a waste gas output of the at least one OBOGS. The inert gas can include nitrogen. An auxiliary source of oxygen can also be provided. Control valves can be used to selectively supply the waste gas output of the at least one OBOGS to the atmosphere or to either of two locations. The oxygen can be used in a passenger compartment of the aircraft and the inert gas used in either a fuel tank or cargo bay of the aircraft.