Robert Lee Stewart (born August 13, 1942)[2] is an American retired military officer and NASA astronaut who was a brigadier general of the United States Army.

He has military and civilian experience in 38 types of airplanes and helicopters and logged approximately 6,000 hours total flight time.

His technical duties in the Astronaut Office included: testing and evaluation of the entry flight control systems for STS-1 (the first Space Shuttle orbital mission), ascent abort procedures development, and payload coordination.

While in training for his scheduled third flight (STS-61-K, ultimately cancelled as a result of the Challenger disaster) in 1986, Stewart was selected by the Army for promotion to brigadier general.

STS-41-B Challenger (February 3–11, 1984) was launched from Kennedy Space Center, Florida, and returned to land there 8 days later.

During the mission, Stewart and fellow astronaut Bruce McCandless participated in two extravehicular activities (EVAs) to conduct first flight evaluations of the Manned Maneuvering Units (MMUs).

[1] STS-51-J Atlantis (October 3–7, 1985) was launched from Kennedy Space Center, Florida, and after 98 hours of orbital operations returned to land at Edwards Air Force Base, California.