Airmen of the 21st Space Wing’s 721st Mission Support Group at Cheyenne Mountain AFS, Colo., recently practiced “button-up” procedures—closing the mountain’s monstrous blast doors. “The blast doors are three-and-a-half feet thick, weigh 25 tons, and are normally closed by a hydraulic pump in 30 to 45 seconds,” says 1st Lt. Jeff Crepeau, 721st MSG executive officer. With muscle power alone, they can be closed in 4.5 minutes.
Pentagon Cancels $6B GPS Ground System Contract
April 20, 2026
The Pentagon has canceled its contract with RTX to field a ground segment to manage its most capable GPS satellites, a more than 15-year effort beleaguered by software development issues and cost overages.