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Donahoo, M. E.

Publications and source records attributed to Donahoo, M. E..

Contamination of spacecraft by recontact of dumped liquids

Liquids partially freeze when dumped from spacecraft producing particles which are released into free space at various velocities. Recontact of these particles with the spacecraft is possible for specific particle sizes and velocities and, therefore, can become contamination for experiments within the spacecraft or released experiments as a result of waste and potable water dumped from Space Shuttle. An examination of dump characteristics was conducted on STS-29 using both on-board video records and ground based measurements. A preliminary analysis of data from this flight indicates particle velocities are in the range of 30 to 75 ft/sec and recontact is possible for limited particle sizes.

Fowler, M. E.↗

NASA/DOD earth orbit shuttle traffic models based on end to end loading of payloads

An analysis of the spacecraft configurations and space missions for the Earth Orbit Shuttle traffic model based on an end-to-end loading of payloads is presented. Two possible reusable tugs are considered. The space missions are described with respect to the following: (1) number of earth orbit shuttle flights by inclination, (2) total payloads to orbit, (3) energy stages required, and (4) characteristics of reusable tug.

Kincade, R. E.↗

NASA/DOD earth orbit shuttle traffic models based on side by side loading of payloads

An analysis of the spacecraft configurations and space missions for the Earth Orbit Shuttle traffic model based on side-by-side loading of payloads is presented. The reusable tugs to be employed for the mission are examined. The space missions are described with respect to the following: (1) number of Earth Orbit Shuttle flights by inclination, (2) total payloads to orbit, (3) energy states required, and (4) characteristics of reusable tug.

Kincade, R. E.↗