THE Bush Administration is preparing to spend $10 billion (£5.5 billion) to equip America’s 6,800 commercial jets with a system to defend them against shoulder-fired missiles.

The Department of Homeland Security has begun financing tests of infra-red laser-based technology used by US military aircraft.

An American Airlines Boeing 767, the type of aircraft that the September 11 hijackers flew into the World Trade Centre, is one of three commercial aircraft that by the end of this year will test the system, according to yesterday’s New York Times. The Department has earmarked $120 million for the testing, and has been directed by Congress to move rapidly to adapt military technology to commercial jets.

“We are long overdue for a passenger aircraft to be taken down by a shoulder-launched missile,” John L. Mica, a Republican congressman who is pushing for the systems, said.

According to a recent study by the US Congress, more than 350,000 shoulder-fired missiles exist in government arsenals worldwide. But hundreds, perhaps thousands, are missing and can be bought on the black market cheaply.

The most popular are the US-made Stingers, widely used during the Soviet occupation of Afghanistan, and the Soviet-made SA7s. Backers of the system point to the neardisaster that befell a Boeing 757, chartered by an Israeli airline, as it took off from Mombasa airport in Kenya in 2002. Two shoulder-fired missiles were fired at the aircraft, but they narrowly missed.

Last November, an Airbus A300 cargo aircraft flown by DHL was struck by a missile on take-off from Baghdad airport. The aircraft lost hydraulic power but was able to land.

The companies competing to build the defence system, which would attach to the belly of the aircraft, are Northrop Grumman and Britain’s BAE Systems. The device would rely on sensors that detect a heat-seeking missile.

The potential cost of the programme has drawn critics. They point to recent studies, one by the Homeland Security Department itself, which concluded that infra-red systems would be useless, or only marginally effective, against several types of shoulder-fired missiles.

The Rand Corporation has also said that lorry bombs and luggage bombs pose far greater threats to commercial aircraft. The Bush Administration also concedes that there is no credible threat of a planned missile attack in the US. Christopher Cox, a Republican congressman, said the programme was being driven by politics and lobbyists rather than reality.

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