An unnamed defence official in Washington told the Associated Press that the plane was on a refuelling mission to Afghanistan at the time.

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The Nimrod spy plane exploded on 2 September 2006, shortly after undergoing air-to-air refuelling.

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The original jumbo jet could carry twice as many passengers as the next largest plane then flying and had a greater range, allowing, for example, a long transatlantic flight without refuelling.

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