KC-135 Overpressure

Seeing that bit on the E-8 JSTARS overpressurizing a fuel tank in flight reminded me of another overpressure incident, this time a catastrophic failure. Fortunately, this one happened on the ground.

Doing a depot level maintenance on the bird, a civilian contractor was testing the jet to see if the cabin was properly sealed to maintain pressure. He plugged the relief valves, and started pumping in air. His pressure gauge was home-made, and he failed to note that it had in fact gone all the way around, and was on its second trip around the dial. Jets are built to take a good deal of pressure differential, but not that much. The fuselage failed completely.