A new section titled 'Other Spacecraft' has been posted to the Field Guide. This section will highlight space vehicles that do not fit into other categories. Among them is the Manned Maneuvering Unit used by space shuttle astronauts during extravehicular activity. The MMU was used on three shuttle missions in 1984 - STS-41B, STS-41C and STS-51A. On all three flights MMU #3, pictured at right hanging in the Udvar-Hazy Center, was lofted to provide astronauts an untethered access to work in space. This freedom of flight can be compared to riding a motorcycle, where the sole rider is openly exposed to the environment. While still protected by the EMU (Extravehicular Mobility Unit or spacesuit), the astronaut is free to travel through space under their own power. While its first two flight helped shake down the MMU, it proved its worth with the capture of two wayward satellites during STS-51A.
Only three MMUs were made by Lockheed-Martin, and only one was flown. MMU #2 is at the US Space and Rocket Center, while #1 has been reported at Johnson Space Center (if anyone has any info on this, please pass it on!). Several models are found at various museums, and it has been used as a space simulator in many interactive displays. It was also featured in a Discovery Channel commercial:
And this commercial always reminded me of a print I own from artist Kim Poor titled "Attitude Hold".