A flight spare is a copy of a spacecraft or spacecraft part which is held in reserve in case it is needed for the mission. Flight spares are built to the same specifications as the original equipment (the "flight model"), and can be substituted in the case of damage or other problems with the flight model, reducing launch delays. The extra cost of building a flight spare can be justified by the enormous cost of delaying a launch by even a short amount of time.
Flight spares are constructed as contingencies. As such, spare parts may be swapped onto a craft before launch, or completed spare spacecraft may be launched if the flight model is lost.
NASA has two basic types of spares, development spares and operational spares. NASA makes a determination about which parts need spares based on whether parts are custom built, and the lead-time for procurement. 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.[2]
The flight spare can also be useful during a space mission if a change to the original plan is required, since the effect of changes can be safely tested on the ground.
Reusageedit
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]
New missions for old hardwareedit
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. The Mariner 10 flight spare is such an example.[1]
^Office of Inspector General, Office of Audits (2017-10-05). "NASA's Management of Spare Parts for its Flight Projects" (PDF). nasa.gov. NASA. Retrieved 2020-10-18.
flight, spare, flight, spare, copy, spacecraft, spacecraft, part, which, held, reserve, case, needed, mission, built, same, specifications, original, equipment, flight, model, substituted, case, damage, other, problems, with, flight, model, reducing, launch, d. A flight spare is a copy of a spacecraft or spacecraft part which is held in reserve in case it is needed for the mission Flight spares are built to the same specifications as the original equipment the flight model and can be substituted in the case of damage or other problems with the flight model reducing launch delays The extra cost of building a flight spare can be justified by the enormous cost of delaying a launch by even a short amount of time 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 Contents 1 Primary function 2 Reusage 2 1 New missions for old hardware 2 2 Flight spares on display 3 References 4 See alsoPrimary function editFlight spares are constructed as contingencies As such spare parts may be swapped onto a craft before launch or completed spare spacecraft may be launched if the flight model is lost NASA has two basic types of spares development spares and operational spares NASA makes a determination about which parts need spares based on whether parts are custom built and the lead time for procurement 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 2 The flight spare can also be useful during a space mission if a change to the original plan is required since the effect of changes can be safely tested on the ground Reusage editFlight 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 New missions for old hardware edit 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 Reuse type legend Flight spare Design reuse Component Origin Attitude control computer Galileo Bus Voyager program Command and data subsystem Galileo High and low gain antenna Voyager program Medium gain antenna Mariner 9 Power distribution unit Galileo Propellant tank Space Shuttle auxiliary power unit Pyrotechnic control Galileo Radio frequency traveling wave tube assemblies Ulysses Solid rocket motor Space Shuttle Payload Assist Module Star scanner Inertial Upper Stage Thrusters Voyager program Flight spares on display edit Since few space probes return to Earth intact flight spares are useful for posterity and may go to museums The Mariner 10 flight spare is such an example 1 References edit a b Spacecraft Mariner 10 Flight Spare Retrieved 2020 10 18 Public Lessons Learned Entry 0724 NASA Spares Philosophy Office of Inspector General Office of Audits 2017 10 05 NASA s Management of Spare Parts for its Flight Projects PDF nasa gov NASA Retrieved 2020 10 18 The Magellan Venus Explorer s Guide Chapter 4 The Magellan Spacecraft nasa gov NASA Retrieved 2020 10 18 See also editOrbit Replaceable Units Spare part nbsp This spacecraft or satellite related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Flight spare amp oldid 1190384560, wikipedia, wiki, book, books, library,
