In 1961, three years before a US astronaut walked in space, USAF Officer Whitsett imagined how astronauts could "fly" in space without tethers while working at the
Air Force Institute of Technology (AFIT) at
Wright-Patterson Air Force Base, Ohio. In 1962, he studied the human body's response to weightlessness. He developed the mathematical model for human mass distribution, center of mass, moments of inertia, and body movement. Whitsett used a
reduced-gravity aircraft to validate his model, but the test was inconclusive. He started work at NASA in 1966 while on assignment from the USAF as the experiment coordinator for the crewed spaceflight program. Whitsett then worked for the
Apollo Applications Program (AAP),
Project Apollo, and Skylab. Project Apollo Missions had 170 hours of extravehicular, Whitsett developed movement devices for the lunar surface environment, including a hand-held, self-propulsion gun. In 1973, Major Whitsett headed the M509 experimental program while assigned to the Manned Spacecraft Center and the Air Force Space and Missile Systems Organization (SAMSO). His control of development objectives, costs, and his ability to consolidate research between USAF and NASA was noted by administrators. Whitsett highlighted the backpack program: "An experimental MMU tested onboard the NASA Skylab Program orbital workshop established key piloting characteristics and capability base for future MMU systems" and yielded the operational MMU used on the Shuttle missions. M509 demonstrated
astronaut maneuvering unit (AMU) flying qualities for future AMU design requirements and projected EVA capabilities. The entire EVA system included two jet-powered AMUs, an automatically stabilized maneuvering unit (ASMU), and a handheld maneuvering unit (HHMU). The ASMU was powered by a high-pressure nitrogen propellant tank and battery. Pilot directed jets supplemented a control gyro and reaction stabilization jets. The ASMU provided propellant and instrumentation for evaluation of the HHMU mode. The ASMU used 14 fired thrusters located in various positions on the backpack. Arms extending from the backpack had thruster controls. Flying the units inside Skylab, three crew members flew four experiment flights. They tested operations procedures and analyzed flight qualities reporting on progress to mission control. Flying the AMU, the right hand controls roll about all three axes and the left hand controls movement forward, back, left, and right. The gyro with a computer enables hands free, station keeping operations. ==Collier Trophy==