Engineering topics
Publications and source records attributed to Boyd, William C..
The results of a cooperative effort to develop fluid components and systems that facilitate on-orbit servicing are discussed. The evolution from manual couplings to semi-automatic dual line interfaces to fully automatic multi-line resupply interfaces is traced. Hardware designs are presented in the context of solutions to requirements. Test data and user evaluations are reviewed.
Propulsion system configurations for future NASA and DOD space initiatives are driven by the continually emerging new mission requirements. These initiatives cover an extremely wide range of mission scenarios, from unmanned planetary programs, to manned lunar and planetary programs, to earth-oriented (Mission to Planet Earth) programs, and they are in addition to existing and future requirements for near-earth missions such as to geosynchronous earth orbit (GEO). Increasing space transportation costs, and anticipated high costs associated with space-basing of future vehicles, necessitate consideration of cost-effective and easily maintainable configurations which maximize the use of existing technologies and assets, and use budgetary resources effectively. System design considerations associated with the use of storable propellants to fill these needs are presented. Comparisons in areas such as complexity, performance, flexibility, maintainability, and technology status are made for earth and space storable propellants, including nitrogen tetroxide/monomethylhydrazine and LOX/monomethylhydrazine.
The NASA Space Shuttle's Orbital Maneuvering Engine (OME) has been investigated as the basis for an enhancement of Shuttle operational flexibility. The Johnson Space Center has given attention to an upgrading of the OME through the use of a gas generator-driven turbopump to raise engine specific impulse. Hardware tests have demonstrated the projected performance gains, which will yield an enhanced, intact ascent-abort capability, as well an an improved on-orbit payload and altitude capability. Attention is given to the application of these capabilities to the Hubble Space Telescope's deployment.
The results of a pre-development component demonstration program on the use of a gas generator-driven turbopump that increases the Space Shuttle's Orbital Maneuvering Engine (OME) operating pressure are given. Tests and analysis confirm the the capability of the concept to meet or exceed performance and life requirements. Storable propellant upper stage concepts are also discussed.