"Our No. 1 manning problem in the Air Force is manning our unmanned platforms," said Gen. Philip M. Breedlove, Air Force vice chief of staff. Without civilian contractors, U.S. drone operations would grind to a halt. About 168 people are needed to keep a single Predator aloft for 24 hours, according to the Air Force. The larger Global Hawk surveillance drone requires 300 people. In contrast, an F-16 fighter aircraft needs fewer than 100 people per mission.

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