Secrecy. The USAF routinely orders enough (?) spare parts for secret equipment, then scraps all the tooling. They love shredding/burning amything classified. T

Secrecy. The USAF routinely orders enough (?) spare parts for secret equipment, then scraps all the tooling. They love shredding/burning amything classified. Then the system gets extended to a longer life, and an expensive new store of spare parts gets rolled into upgrades. Full dosclosure: old guy who experienced enough of USAF to be a touch cynical about procurement.