For the team of aeronautics experts and TV producers, the moment when a Boeing 727 jet crash-landed into the Mexican desert, ripping its fuselage in half, marked the fulfilment of a dream. The explosive sequence, screened last night in the Channel 4 documentary The Plane Crash, was hatched four years ago as a seemingly insane and certainly highly dangerous proposal, which alarmed broadcasters and safety officials alike.
The idea, to deliberately crash a 170-seat aircraft, was seized upon by scientists, experts and elite pilots as a once-in-a-generation opportunity to study the mechanics of a crash in real time. Flight experts wanted to create a serious but survivable "forced-landing". The jet would not carry real passengers but crash-test dummies, including three special models worth £100,000 each. Accelerometers would measure the G-forces withstood by the "passengers" and the 140mph impact would be captured by dozens of cameras inside the aircraft, on the runway, on a following "chase" plane and on the pilot's helmet.
The concept, first sent by producer Geoff Deehan as a one-line, wish-list proposal, "crash a passenger jet", to the Channel 4 executive David Glover, had to offer more than simply dramatic footage for a ratings-hungry broadcaster. The data collected would allow scientists to study the crashworthiness of the airframe and cabin, the impact of crashes on the human body, and look at measures to increase passenger survivability. Although car-makers regularly perform impact tests, no commercial airline had dared conduct its own crash. "It was an insanely difficult escapade," said Glover, C4's science commissioning editor. "It has taken four years to make this happen. This was our Heart of Darkness. I thought we were jinxed at times."
The project was delayed when the authorities refused to sanction the experiment. US aviation officials said the crash could not take place on its soil, and the programme's co-producer, National Geographic, pulled out. "The great fear was that we would lose control of the plane and it would fly into a town," Glover admits. The jet they intended to use contained depleted uranium in its wings, threatening a minor environmental catastrophe.
Eventually, Mexico's civil aviation authority granted permission for the British production company Dragonfly and the Discovery Channel to stage the crash in a remote and uninhabited corner of the Sonoran Desert. The Boeing was piloted by James "Jim Bob" Slocum, a captain with the courier company FedEx, who had previously survived three plane crashes.
The crew parachuted from the jet minutes before impact. It was then flown remotely, from an aircraft following behind, and plunged to Earth at 1,500ft per minute. The impact destroyed the cockpit and front rows of seat, and tore away the landing gear. Emergency crews formed an exclusion zone around the site and no damage to people or property was reported.
Scientists, including Anne Evans, a former senior investigator with Britain's Air Accidents Investigation Branch who examined the Lockerbie crash, pored over the wreckage. They concluded that the pilots and front-row passengers would almost certainly have been killed (a warning to first-class ticket-holders, perhaps). Those in the centre would have survived with minor injuries. Passengers at the rear would have been mostly unharmed.
When the jet came down, Mr Glover, observing from a desert viewing point, admitted he was a nervous wreck: "The nightmare scenario was that the plane cartwheeled down the runway, destroying all our scientific equipment; then we would have learned nothing. But the scientists came away really pleased because this replicated the most common form of crash."
Engineers will use the evidence collected to help strengthen the cockpits and front sections of airliners. Channel 4 is, however, keen to stress that the chances of being involved in a jet crash are negligible. "I was offered an upgrade nearer the front on the flight back from Mexico and I didn't turn it down," Mr Glover said. He is now looking for other "big bang" projects. Recreating a train crash, or a nuclear meltdown? "Whatever it is, it has to have a scientific purpose," he said. "But I wouldn't be able to do any of this without the backing of the team at Channel 4."
The Plane Crash is repeated at 9pm tonight on 4Seven and is available on the 4oD catch-up service