The fake: In true Top Gear style, presenter James May is racing against Richard Hammond in a caravan attached to a zepplin airship. He accidentally flies over Norwich airport, provoking police to intervene. After struggling with the controls, May calls for help shouting "Mayday, Mayday!" before crashing the ship in a field.

What really happened: The BBC show is famed for its ourageous stunts and this was one of the many slapstick moments which were faked. Although May appeared to be flying alone, a professional was on board to control the more difficult moves and the crash was revealed to be a controlled accident.

Steve O'Brian of Sterling Helicopters, who supplied the police chopper, said: "The whole event was set up. It was completely scripted, there was no real emergency - we were hired to play along."

Watch highlights from the stunt here:

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