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The application of cryogenic fluid storage systems to manned spacecraft is considered attractive primarily because of the substantial weight and volume saving afforded compared with high-pressure gaseous storage at ambient temperature. The major use of the stored fluids has been as a metabolic support (oxygen) and as reactant supply (hydrogen and oxygen) to the fuel cell for power generation. In addition cryogenic helium is used for descent propellant tankage pressurization aboard the lunar module. The subsystems developed for the NASA Gemini program, the firts full-scale operational application of this type of equipment, are discussed as a baseline for comparison with more advanced designs for subsequent programs. State-of-the-art design improvements are presented in some detail. Current programs (i.e., Apollo, Lunar Module, Biosatellite (primate), Manned Orbiting Laboratory, and the Air-lock Module) utilize cryogenic storage and supply subsystems for the usages mentioned earlier.

The laser, as a metallurgical fusion welding process, was little more than a dream approximately four years ago. Many uses have been proposed for the laser but one of the most promising uses for the process, to the welding engineer and to the designer of aerospace hardware, is its now proven capability as a fusion welding process. This paper discusses where, in metallurgical joining, the laser can be employed to join members which would be impossible to fusion weld by any other fusion welding process with any degree of reliability. There are now indications that the laser process “begins” where the electron beam process “leaves off” in the fusion welding of small components in close proximity to glass or ceramic seals. This paper also goes into detail relative to the application of the process on various materials, its effect on materials, and on various configurations which appear to be particularly adaptable for the process.