B of B day at Wattisham in the mid 50's.
In preparation for the crazy flying display by a Chippy, the commentator built up a story about a prisoner who had escaped from a nearby jail, and was believed to be heading this way
Sure enough, at the right moment, a denimed figure burst from the crowd and leapt into the Chippy parked in front of the public enclosure. The guy who had been crouching in the other seat out of sight to the crowd, promptly fired the cartridge and away they went.
It lurched around a no more than 200ft for a while the commentator kept saying "oh dear he cannot fly" etc etc.
They then did a horrible flat skidding turn in front of the officers enclosure while the commentator said " oh, he's going to stall", and they did, "Oh, he's going to crash", and he did.
It hit the ground in a more or less level attitude, the undercarriage spronged off, the wings sagged, and a distinct kink appeared in the fuselage just behind the canopy.
As the dust settled the two guys got out and walked off, closely followed by the Groupie who did not look very happy.
This is referred to in my book The Royal Air Force At Home. The Chipmunk was; WP806 of the Station Flight. The incident was on 17th September 1955.
FB