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
Criticism of the Space Shuttle program Criticism of the Space Shuttle program Criticism of the Space Shuttle program stemmed from claims that NASA's Shuttle program failed to achieve its promised cost and utility goals, as well as design, cost, management, and safety issues. More specifically, it failed in the goal of reducing the cost of space access. Space Shuttle incremental per-pound launch costs ultimately turned out to be considerably higher than those of expendable launchers. By 2011, the incremental cost per flight of the Space Shuttle was estimated at $450 million, or $18,000 per kilogram (approximately $8,000 per pound) to low Earth orbit (LEO). By comparison,