This page no longer updated from 31 October 2001. Latest version can be found at www.astronautix.com

astronautix.com Shuttle MMU

STS-41-B
STS-41-B
View of Astronaut Bruce McCandless during EVA

Credit: NASA. 52,329 bytes. 507 x 473 pixels.


Class: Manned. Type: Space Suits. Nation: USA. Agency: NASA.


STS-41-BSTS-41-B - View of Astronaut Bruc McCandless during EVA

Credit: NASA. 30,305 bytes. 470 x 472 pixels.


The shuttle MMU Manned Maneuvering Unit was designed for maneuvering untethered from the shuttle. It was used on several satellite retrieval missions in the early 1980's. After the shuttle disaster, use of the unit was discontinued on safety grounds.


STS-41-BSTS-41-B - Close-up view of Astronaut McCandless during his EVA

Credit: NASA. 50,778 bytes. 481 x 474 pixels.


The MMU was a one-man, nitrogen-propelled backpack that latched to the Shuttle EMU spacesuit's PLSS life support system. Using rotational and translational hand controllers, the crewmember could fly with precision in or around the orbiter cargo bay or to nearby free-flying payloads or structures, and could reach many otherwise inaccessible areas outside the orbiter. Astronauts wearing MMU's deployed, serviced, repaired, and retrieved satellite payloads.


STS-41-CSTS-41-C - View of Astronaut Nelson using MMU to examine Solar Maximum Mission Satellite

Credit: NASA. 3,875 bytes. 197 x 351 pixels.


The MMU propellant - non-contaminating gaseous nitrogen stored under high pressure - could be recharged from the orbiter. The reliability of the unit was guaranteed with a dual parallel system rather than a backup redundant system. In the event of a failure in one parallel system, the system would be shut down and the remaining system would be used to return the MMU to the orbiter cargo bay. The MMU, which weighed 140 kg, included a 35-mm still photo camera that was operated by the astronaut while working in space.

STS-51-ASTS-51-A - Astronat Dale Gardner using MMU to travel to Westar VI satellite

Credit: NASA. 16,158 bytes. 325 x 399 pixels.


Specification



Bibliography:



STS-51-ASTS-51-A - Astronaut Dale Gardner using MMU to travel to Westar VI satellite

Credit: NASA. 59,085 bytes. 618 x 456 pixels.



STS-51-ASTS-51-A - Astronaut Dale Gardner using MMU to travel to Westar VI satellite

Credit: NASA. 50,156 bytes. 611 x 468 pixels.



Back to Index
Last update 12 March 2001.
Contact Mark Wade with any corrections or comments.
Conditions for use of drawings, pictures, or other materials from this site..
© Mark Wade, 2001 .