Bouncing Bombs on Brean Down (1943)

On the tip of Brean Down, a rocky promontory projecting out into the Bristol Channel from the North Somerset coast, there are a large number of derelict military installations and buildings. As one crests the hill on the landward side of the site, the first thing that catches the eye is a Victorian barrack block. This is part of Brean Down Fort, built in the 1860s and  partially destroyed on the 6th July 1900 when a drunken artilleryman fired a ball cartridge down into one of the ventilator shafts serving the main magazine. This reckless act caused a catastrophic explosion which vaporised the shooter and rendered the fort temporarily unusable. 

The second noticeable feature on this dramatic wind-swept headland is the Second World War gun battery which was overlaid onto the original fort in 1939. A control bunker, two 6-inch naval gun positions and a couple of searchlight posts remain - as do the hard-standings for numerous Nissen huts. The guns, of course, are long gone.

Searchlight building and rails - Brean Down

There is one feature that defies immediate identification though. A pair of rails running for a distance of eighty feet with a concrete platform at the western end. On closer examination one can see that the valley in which the tracks sit has been levelled by excavation to the depth of 7'6" at the landward end.

To understand why the rails are on Brean Down and the circumstances of their use, one needs to delve into the records of the Department for Miscellaneous Weapons Development (1941-45) for it was DMWD engineers and scientists (colloquially known as the 'Wheezers and Dodgers') based at HMS Birnbeck in Weston-super-Mare who were responsible for them. Indeed, the rails were installed to test a unique and innovative new weapon - Top Secret Project No. 67 - 'Ricochetting Projectile - Baseball'.

Interestingly DMWD Project 67 has a direct link with one of the most iconic missions flown by the Royal Air Force during the Second World War. This was Operation Chastise - the Dambusters Raid  - of 16 / 17th May 1943. Men of the famous 617 Squadron managed to breech a number of German dams using an 'Upkeep bouncing bomb'. 

But what's the connection with the Wheezers and Dodgers of HMS Birnbeck? Well the story starts in a laboratory near Heathrow and finishes on the North Somerset coast. Let me elucidate.

In testing the cylindrical 'Upkeep' bomb, and its' predecessor the 'Highball' the Admiralty had been asked to source suitable sites along the eastern coast of England and manage the retrieval of dropped test bombs. Lieutenant Commander L.H.M. Lane RNVR of the DMWD was appointed as the Royal Navy's man on this RAF programme - a programme which was centred on the repurposed Road Research Laboratory at Harmondsworth. There, a team under the leadership of Barnes Lewis of Vickers (Weybridge) Ltd were working with the Air Ministry on the dams project. Lane would help on 'Highball' and'Upkeep' but would also look for opportunities on behalf of the Admiralty.

The site of the Road Research Laboratory nr Heathrow

It's fair to say that not withstanding the need for Admiralty involvement there was a bit of inter-service rivalry in the very early days. Amongst Barnes Wallace's papers at the National Archives there is a letter dated 9th May 1941 from the Air Ministry to Vice Admiral Tom Phillips bemoaning the fact that the 'Vickers salesman', Barnes Wallace, 'is pushing his wares through naval channels' (I paraphrase).  An interesting aside to what became a very effective collaboration.

Notwithstanding the tensions and scepticism though, the DMWD were keen to tap into Barnes Wallace's fertile bran and hence, amongst others, Project No. 67 was born. The plan was to develop a version of the RAFs 'bouncing bomb' that could be fired from the deck of a ship (initially for M.T.B's) or from a static ramp onshore. A ricochetting bouncing bomb would be much faster that a torpedo and could be highly effective against enemy ships and 'invasion barges'. As the DMWD technical specification stated, 'Baseball' was an 'explosive filled 18' or 12' ball fired from a smooth bore tube at a small angle to the surface of the sea. Under these conditions the ball would progress in long low bounces with a remarkably small deviation from the line of fire'. 

Mosquito dropping 'Highball' - Lane papers, National Archives

Baseball specification - DMWD Technical History #24, National Archives 

The DMWD team on HMS Birnbeck at Weston-super-Mare set to work making prototypes starting with a reduced scale sphere to investigate rotation, size, density, moment of inertia, speed and height of launching. The DMWD Project 67 file in the National Archive tells how a rocket catapult would be used as the means of propulsion as the launching speed could be controlled within wide limit by varying the number of rockets used. In trialling the prototype the rocket fired catapult carriage would be propelled down the track before coming to to a hard stop. The momentum gained during the rocket propelled run-in meant the sphere would be propelled out of the tube, skipping across the water to hit a designated target area. At Brean Down the stop would be achieved through the installation of hydraulic rams held in a solid block of concrete strapped to a steel grill embedded in concrete (the surface of which can be seen in the first image above). 

Baseball carriage specification - DMWD Technical History #24, National Archives

Three trials were undertaken at Brean Down under the control of the DMWD team at HMS Birnbeck. All consisted of an 18' 'Baseball' weighing 250 pounds. The trials involved rotated and unrotated spheres - the former involving both forward-spin and back-spin. The results of the trials, which took place on the 15th Feb 1943 and the 27th Feb 1943 were mixed - to say the least. We have the official reports and an eye-witness account and the two create an entertaining contrast.

From the official reports, the first trial entailed the use of two rockets on the trolley and showed there was insufficient power to project the sphere out across the sea. There was also considerable debris from the starting pit once the rockets were fired. For the second and third experiments which took place on the second specified date, a wall was built at the back of the starting pit. Trial II with four rockets went reasonably well, but Trial III with six rockets was a fiasco. Travelling at 230 ft per second (160 mph), the trolley ploughed through the 'retardation point' taking the hydraulic ram assembly with it and ended up 80 yards out to sea on the rocks below. 

In his book 'The Secret War: 1939-45' Gerald Pawle helpfully provided a much richer description of the third and final Brean Down 'Baseball' trial'.

The stage was set for the launching of the missile. The small party gathered on the ridge behind the trolley, with its twelve (sic) two-inch rockets, waiting tensely for the signal to fire, no one quite knowing what to expect. When the firing key was pressed the trolley, enveloped with flame, hurtled down the track like a meteor. With a shattering roar it drove straight through the buffers and the massive blast wall disintegrated. The air was filled with a whirling mass of sandbags, wite hawsers, and pieces of steel, and the trolley, its rockets still belching tongues of flame, vanished from sight over the cliff!

Later version of Baseball at Middle Hope - Lane Papers, National Archives

The HMS Birnbeck team were not discouraged though. Although the Brean Down site was abandoned on account of retrieval from the water being problematic in that location, the project continued. Subsequently, two sets of tracks were build at Middle Hope further up the coast - one at sea level, the other on a bluff to replicate the height of a ship. Looking at the image above, it seems the later spheres were bigger and that the means of propelling them had evolved. In the immediate aftermath of the Brean down failure though, the rocket trolley was simplified using cheaper and more easily sourced materials 'Woolworths style' in an effort to reduce the cost of replacing lost components. Trials continued until August 1945 at which point the project was closed down.

Did Barnes Wallace visit Birnbeck Pier? Well, he was closely involved in this and other projects but there is no evidence that he did so. Minutes of meetings show that when the senior stakeholders met, it was in Central London or at Weybridge. Who knows though, he might have - but irrespective of whether he did attend the Brean Down trials personally, the link between Wallace and the Wheezers and Dodgers was strong.

Note: The North Somerest Council's  Birnbeck Pier Restoration Project has been made possible thanks to over £44m in external funding secured from the UK Government, The National Lottery Heritage Fund, National Heritage Memorial Fund and Historic England.

 

The research that I’m carrying out for the project has been made possible thanks to funding from the council’s social value agreement with its contractor, Mackley.