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 Pathfinder Space Shuttle Pathfinder The Space Shuttle Orbiter "Pathfinder" (unofficial Orbiter Vehicle Designation: OV-098) is a Space Shuttle test simulator made of steel and wood. Constructed by NASA in 1977 as an unnamed facilities test article, it was purchased in the early 1980s by the America-Japan Society, Inc. which had it refurbished, named it, and placed it on display in the Great Space Shuttle Exhibition in Tokyo. The mockup was later returned to the United States and placed on permanent display at the U.S. Space & Rocket Center in Huntsville, Alabama, in May 1988. Originally unnamed, the simulator was built at