Reminds me of when they were doing dummy bomb drops over Orford Ness with the Victors, they lined up for a bomb run but the doors jammed shut and so the bomb didn't drop. So they aborted to the nearest airfield which was RAF Woodbridge, landed and parked up, then managed to pry the door open...and the dummy bomb promptly fell out onto the concrete.

Turns out it had been resting on the doors all the way back, and since it had been dropped if it was real then it would have armed itself, and then probably exploded as the aircraft descended for landing.
Needless to say, adjustments were made to protocols.