|Hawkes, Nigel. Space Shuttle. New York: Gloucester Press, 1982: 33.||"The speed of a space shuttle in orbit is about 17,580 miles an hour."||7860 m/s
|"Space Shuttle." Microsoft Encarta 98 Encyclopedia. 1993-1997 Microsoft Corp.||"The SRBs take the space shuttle to an altitude of 45 km (28 mi) and a speed of 4973 km per hour (3094 mph) before they separate and fall back into the ocean to be retrieved, refurbished, and prepared for another flight."||1380 m/s
(at booster separation)
|Dunn, Marcia. "The End of the Challenger." AP Online, 19 May 2000.||"Challenger was traveling at a speed of 18,000 miles an hour, at a height of 46,000 feet when it blew up."||8000 m/s
(at Challenger explosion)
|Collins Michael. Liftoff: The Story of America's Adventure in Space. New York: Grove Press, 1988: 69.||"Speed: 17,460 miles per hour."||7,800 m/s|
|"NASA Charts Course to Sail the Stars on Largest Spacecraft Ever Built." Business Wire, 2000.||"The space shuttles on-orbit speed of five miles per second."||8000 m/s
The space shuttle was developed by the National Aeronautics and Space Administration, more commonly known as NASA. The vehicle consists of a winged orbiter, two solid-rocket boosters, and an external fuel tank. As with previous spacecraft, the shuttle is launched from a vertical position. Liftoff thrust is derived from the orbiter's three main liquid-propellant engines and the boosters. After two minutes, the boosters use up their fuel, separate from the spacecraft, and after deployment of parachutes are recovered following splashdown. During this time, the speed of the shuttle is about 1400 meters per second.
After about eight minutes of flight, the orbiter's main engines shut down; the external tank is then jettisoned and burns up as it reenters the atmosphere. The orbiter meanwhile enters orbit after a short burn of its two small Orbiting Maneuvering System (OMS) engines. At this time, its top speed is an amazing 8,000 meters per second! To return to earth, the orbiter turns around, fires its OMS engines to reduce speed, and, after descending through the atmosphere lands like a glider.
After four orbital test flights (1981-1982) of the space shuttle Columbia, operational flights began in November of 1982. On January 28, 1986, a shuttle exploded shortly after takeoff, killing all seven astronauts. Shuttle flights were suspended until September 1988, while design problems were corrected, and then resumed on a more conservative schedule; NASA was forced to reemphasize expendable rockets to reduce the cost of placing payloads in space. By the end of 2000, 102 missions had been completed and five different orbiters had been seen in service.
Inna Sokolyanskaya -- 2001