Engineering Papers⌕ Search

Engineering topics

Hammock, D. M.

Publications and source records attributed to Hammock, D. M..

8 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Future capabilities and commercial opportunities for materials processing in space

The development of the Space Station and its application to materials processing are studied. The proposed components and capabilities of the Space Station are described. The advantages the modular Space Station configuration will provide to its users are discussed. The functions of the laboratory module and free flying platforms of the Microgravity and Materials Processing Facility (MMPF) are examined; microgravity science research and the development of commercial materials processing technologies are conducted in the MMPF. The equipment of the Commercial Materials Processing Support Facility and the designs of attached- and free-flying platforms are analyzed.

Hammock, D. M.↗
NASA NTRS1975

Mission roles for the Solar Electric Propulsion Stage (SEPS) with the space transportation system. Volume 1: Executive summary

A study was conducted to determine the characteristics of solar electric propulsion stage (SEPS) for the space transportation system. Emphasis is placed on the rationale leading to the concepts for the development and operations program which enhances the cost effectiveness of the SEPS operating with the space transportation system. The approach in describing design concepts and configurations is concerned with the decision controlling factors and selection criteria. The mission roles for the SEPS in accomplishing proposed space activities are defined.

Hammock, D. M.↗
NASA NTRS1963

Vehicle Design for Mars Landing and Return to Mars Orbit

This paper briefly describes three modes for accomplishing the Mars landing mission and compares them on a gross basis to indicate their probable order of merit and to identify design requirements placed on the Mars-excursion module (MEM) by the choice of mode. The paper shows that a flyby-rendezvous mode requiring low weight in earth orbit requires the MEM to enter the Mars atmosphere at velocities ranging from 20,000 to 30,000 ft/sec. The MEM for the flyby-rendezvous mode is not covered in this paper but merits further study. The MEM for the other modes of mission accomplishment begins its active operational sequence in Mars orbit and need not be greatly influenced by the method of delivery to Mars orbit. Parametric studies of the entry problem for two vehicles typifying a ballistic-type and a lifting-body-type were conducted to identify the problems associated with design of a MEM to accommodate the extremes of Mars atmospheric density presently predicted. This brief study indicates that: (a) the presently predicted density extremes of the Mars atmosphere present no serious design problems for a MEM which can operate across the entire band of predicted densities; (b) details of operational requirements and mission objectives will control the choice of configuration rather than entry requirements; and (c) the ballistic-type MEM is lighter and simpler but has less operational flexibility than a high L/D MEM.

Hammock, D. M.↗