Flight spare

It also makes determinations about the quantities of spares, based on whether the part is critical to system operation, failure rate, and the expected life of the part.

Flight spares that go unused in their initial missions are still considered valuable.

A 2017 NASA report on flight spare inventory control mentions hundreds of millions of dollars' worth of inventory, not all of it catalogued properly.

[3] Individual spare components manufactured for one mission may eventually fly on another.

As a cost-saving measure, the Magellan spacecraft was made largely out of such parts:[4] Since few space probes return to Earth intact, flight spares are useful for posterity, and may go to museums.

A complete copy of Mariner 10 was constructed but never used. NASA gave it to the Smithsonian Institution in 1982, which currently displays it in the Time and Navigation exhibition at the National Air and Space Museum . [ 1 ]