RISING majestically after unleashing its destructive cargo, a historic war plane recreates the most famed bombing raid in British history.

Scientists told yesterday how they built a bouncing bomb and became the first team to copy the 1943 Dam Busters attack on the Nazis.

British engineers destroyed a 30ft high and 130ft wide dam which they had specially built on a lake in Canada.

Team leader Dr Hugh Hunt, from Cambridge University, said: "Our pilots had no one shooting at them, the engineers could use things like bowling machines to test their theories, and the whole thing was only at one-third scale – and even then it was hard enough.

"You compare that with the original challenge and you realise what an amazing achievement it was."

Most of the designs and calculations done by Barnes Wallis, who invented the bouncing bomb in the Second World War, have been lost.

Dr Hunt wanted to see how hard it would be to re-create the mission and said the toughest challenge was ensuring the bombs were spinning rapidly as they hit the water.

Lancaster bombers were used in the 1943 mission but so few survive that Dr Hunt had to enlist Second World War DC-4s to hit the dam in Mackenzie, British Columbia.

Channel 4 will show a documentary about the test at 8pm tonight.