Astronaut propulsion unit
An astronaut propulsion unit (or astronaut maneuvering unit) is used to move an astronaut relative to the spaceship during a spacewalk. The first astronaut propulsion unit was the Hand-Held Maneuvering Unit (HHMU) used on Gemini 4. Models Hand-Held Maneuvering Unit The Hand-Held Maneuvering Unit was the EVA "zip" gun used by Ed White on the Gemini 4 mission in 1965. The hand-held gun held several pounds of nitrogen, and allowed limited movement around the Gemini spacecraft. It was also used by astronaut Michael Collins on the Gemini 10 mission in 1966. USAF Astronaut Maneuvering Unit The United States Air Force (USAF) Astronaut Maneuvering Unit (AMU) was designed by the U.S. Air Force, which was planning to use the Gemini spacecraft as part of the Manned Orbiting Laboratory (MOL). The AMU was a backpack using hydrogen peroxide as the fuel. The total delta-v capability of the AMU was about 250 feet per second (76.2 meters per second), roughly three times that of the MMU. The astronaut would strap on the AMU like a backpack, and maneuver around using two hand controllers like that of the later MMU. Because of the fuel, which came out as a hot gas, the astronaut's suit