Criticism of the Space Shuttle program costs through amortization. Development costs were expected to be recouped through frequent access to space. These claims were made in an effort to obtain budgetary funding from the United States Congress. Beginning in 1981, the space shuttle began to be used for space travel. However, by the mid-1980s the concept of flying that many shuttle missions proved unrealistic and scheduled launch expectations were reduced 50%. Following the "Challenger" accident in 1986, missions were halted pending safety review. This hiatus became lengthy and ultimately lasted almost three years as arguments over funding and the safety of the program continued. Eventually the
Space Shuttle made Space Shuttle thermal protection system tiles available to schools and universities for less than US$25 each. About 7,000 tiles were available on a first-come, first-served basis, limited to one per institution. On April 12, 2011, NASA announced selection of locations for the remaining Shuttle orbiters: In August 2011, the NASA Office of Inspector General (OIG) published a "Review of NASA's Selection of Display Locations for the Space Shuttle Orbiters"; the review had four main findings: The NASA OIG had three recommendations, saying NASA should: In September 2011, the CEO and two board members of Seattle's Museum of Flight met