Told to me by an ex Canberra pilot many moons ago, but don't know if true..
He had been on detachment and coming back from overseas found the elevator controls on the Canberra to be very heavy, but as he needed to get back he carried on, after landing he noticed the Nav asking the ground crew to unbutton a large panel or open the bomb doors?
Investigating he had found the Nav had purchased a washing machine or the likes and the helpful guys loading it for him at the other end had lashed the box to the elevator control cables, so he had been humping it back and forth all the way back.