The Italian Job -- a solution

The British papers this week are finding space for a few stories other than the inauguration of Barack Obama and the current credit crunch. One such is the outcome of a competition to solve the forty-year old problem of the end of the film, The Italian Job. The competition was organised by the British Royal Society of Chemistry (why not a mathematical society?). It is good to see mathematical modelling, problem solving and decision making in the news media. So here is the story, courtesy of Britain's Daily Telegraph.

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As cliffhanger endings go, there are few more famous than that of The Italian Job. With their coach dangling precariously over an Alpine ravine, a gang of plucky British robbers – led by Michael Caine's Charlie Croker – face the choice of saving themselves or risking all to retrieve the stash of gold they have stolen from Turin. However, each move they make towards the rear of the coach to reach their haul results in the vehicle inching further over the abyss.

The film ends with the famous words from Croker: "Hang on a minute, lads – I've got a great idea." But what was the idea – and would it have worked?

=== The winning solution -- for which the prize is a holiday in Turin, but no gold.

This IT expert's solution starts with Croker and his gang smashing most of the windows of the coach, using a hard object like a shoe. The windows to the rear, which hang over the cliff, would break outwards, removing their weight. The gang would reach round and smash the windows at the front inwards, to retain their weight. One of the gang should then be lowered by their feet to let the air out of the front tyres, making the coach settle on the ground. Finally, the pipe to the fuel tank, which Godwin estimated would have 36 gallons of diesel left, would be slashed. As the fuel poured away, it would remove 130kg (286lb) from the back of the coach – more than enough for a 90kg man to start removing the gold bars.
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===And for those who like puns ...
"Keep singing The Self Preservation Society," he tells the gang. The chorus starts up again until they all get frogs in their throats. The frogs start to jump up and down, which rocks the bus.

They use the rocks to weigh the end of the bus. "Keep singing, lads."

They sing louder, but now the frogs have gone, their throats get sore. They use the saw to cut the gold bars in half. Two halves make a whole. They pass the gold out through the hole, and jump out.

Still singing, they've now all gone hoarse. They load the gold on to the horses and ride off into the sunset.

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