The Barnes Wallis 'Bouncing Bomb' at Dover Castle (UK)

John Latter, on November 12, 2007, said:

A prototype bouncing bomb remnant recovered off Reculver beach in 1996 and now at Dover Castle. Barnes Wallis' bouncing bombs were used by the Royal Air Force's 617 Squadron (led by Guy Gibson) in the Dambuster Raid of 1943 during the Second World War (also see video link below).

An accompanying plaque reads (abridged):

This is a prototype of the 'bouncing bomb' which was used in the famous Dambuster operation. This operation, which breached the Mohne Dam and Eder Dam in Western Germany, was carried out by No. 617 Squadron of the RAF on 16th May, 1943.

These special bouncing bombs resembled giant garden rollers and needed to spin away from the Lancaster aircraft, which were travelling at 220 mph at a height of 60 ft above ground.

This prototype was drop tested in April 1943 off Reculver beach, Kent and was rediscovered in June 1996 [1].

[1] The BBC only records discoveries made in June 1997

To the left of the plaque is a BBC's "People's Museum" Winner Certificate. The entry for the Dover Castle 'bouncing bomb' on the BBC website [2] is appended below. Note that the BBC states the Lancaster speed to be 240 mph as opposed to the 220 mph quoted above. As in the case of the Pharos and Queen Elizabeth's Pocket Pistol, for example, it is not unusual for 'reputable' sources to give conflicting facts! (and no doubt other examples will come to light as more structures within Dover Castle are researched).

The Dambusters, as they are famously known, have been immortalised in World War Two folklore as a result of their courageous attacks on the dams of the Ruhr. For this type of night-time raid they needed a weapon with a difference, something that could penetrate deep into the dam before exploding, creating a massive shock wave that would rip the dam apart and something that could be timed to explode at a predetermined depth.

Barnes Wallis believed that he could create just what they needed. He began testing with marbles and a catapult on a tub of water in his garden, and continued with a special catapult to project lead spheres with a spin. The tests showed that a 7000lb bomb would be sufficient, and in early 1943 he was informed that he had eight weeks to build the bombs and train the crews.

Initially he was set on spherical bombs, but finally settled on cylinders, to be fitted into the Lancaster bombers in such a way that the bombs could be spun at 500 rpm. They were delivered from 60 ft at 240 mph and travelling at that height and speed made the missions incredibly dangerous.

The bomb was fitted with very precise specifications and had to be used in a very exact way to have any effect at all.

[2] At the time of writing the relevant entry is under "Week 3"

Info on the Dam Busters film:

The Dam Busters is a 1954 British war film, set during the Second World War, and documenting the true story of the RAF's 617 Squadron, the development of the "bouncing bomb", and Operation Chastise [also here] - the attack on the Ruhr dams in Germany. It stars Michael Redgrave as Barnes Wallis, and Richard Todd as Wing Commander Guy Gibson. The movie was based on the books The Dam Busters by Paul Brickhill and Enemy Coast Ahead by Guy Gibson. It was re-mastered and re-released in September 2007 in the UK.

Also see "The Dam Busters" (1955) - Comments and Inaccuracies

The bouncing bomb remnant at Dover Castle is located in the same room of the Naafi* Restaurant as Queen Elizabeth's Pocket Pistol (at the northern end of the room, nearest the Keep).

*"Navy, Army and Air Force Institutes"

Video: Dambuster Raid - LIVE test of a bouncing bomb

Archival film of the only LIVE bomb test (Operation "Upkeep" at Broadstairs, Kent - May 5th 1943) prior to the Lancaster raids of 617 squadron. This clip includings other drop tests of both 617 Lancaster & 618 Mosquito squadrons.

John Latter, on November 23, 2007, said:

Click to see an external view of the 'Naafi Restaurant' Victorian building which also houses Queen Elizabeth's Pocket Pistol and the remnant of the Barnes Wallis 'Bouncing Bomb'.