Captain Bruce McCandless II (born June 8, 1937 in Boston, Massachusetts) is a former naval aviator with the United States Navy and NASA astronaut. In the first of his two space shuttle missions he made the first untethered, free flight using the Manned Maneuvering Unit (pictured below).
In March 1960 he was designated a naval aviator and proceeded to NAS Key West, for weapons system and carrier landing training in the F-6A Skyray.
Between December 1960 and February 1964 he was assigned to Fighter Squadron 102 (VF-102), flying the Skyray and the F-4B Phantom II. He saw duty aboard USS Forrestal and USS Enterprise, including the latter's participation in the Cuban Missile Crisis.
For three months in early 1964, he was an instrument flight instructor in Attack Squadron 43 (VA-43) at NAS Oceana, and then reported to the Naval Reserve Officer Training Corps Unit at Stanford University for graduate studies in electrical engineering.
During naval service he gained flying proficiency in the T-33B Shootingstar, T-38A Talon, F-4B Phantom II, F-6A Skyray, F-11 Tiger, TF-9J Cougar, T-1 Seastar, and T-34B Mentor airplane, and the Bell 47G helicopter. He logged more than 5,200 hours flying time—5,000 hours in jet aircraft.
He was responsible for crew inputs to the development of hardware and procedures for the Inertial Upper Stage (IUS), Space Telescope, the Solar Maximum Repair Mission, and the Space Station Program.
McCandless logged over 312 hours in space, including 4 hours of MMU flight time. He flew as a mission specialist on STS-41-B and STS-31.
This mission marked the first checkout of the Manned Maneuvering Unit (MMU) and Manipulator Foot Restraint (MFR). McCandless made the first, untethered, free flight on each of the two MMUs carried on board.
After eight days in orbit, Challenger made the first landing on the runway at Kennedy Space Center on February 11, 1984.
Discovery landed at Edwards Air Force Base, California, on April 29, 1990.
He was awarded one patent for the design of a tool tethering system that is currently used during Shuttle spacewalks.
He is a fellow of the American Astronautical Society and former president of the Houston Audubon Society.