Space Shuttle gliding and landing; it was originally intended to be outfitted for orbital operations after the test program, but it was found more economical to upgrade the structural test article STA-099 into orbiter "Challenger" (OV-099). An additional test article, dubbed "Pathfinder" (OV-098), was built for form and fit tests, and is on display at the Alabama Space and Rocket Center in Huntsville, AL. "Challenger" disintegrated 73 seconds after launch in 1986, and "Endeavour" was built as a replacement from structural spare components. Building "Endeavour" cost about US$1.7 billion. "Columbia" broke apart over Texas during re-entry in 2003. A Space Shuttle launch
Space Shuttle Space Shuttle The Space Shuttle was a partially reusable low Earth orbital spacecraft system operated by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was "Space Transportation System (STS)", taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development. The first of four orbital test flights occurred in 1981, leading to operational flights beginning in 1982. In addition to the prototype whose completion was cancelled, five complete Shuttle systems were built and used on a total of 135