Purpose of this blog

Dmitry Yudo aka Overlord, jack of all trades
David Lister aka Listy, Freelancer and Volunteer

Sunday, June 10, 2018

No Big Bang

During 1940 Britain came under sustained bombing from the Luftwaffe. Its widely recognized today that an average of 10% of bombs that were dropped on the UK were duds, often called 'UX' or 'UXB' in reports, this stands for UneXploded Bomb. Today the number of bombs dropped on the UK is generally given in total tonnage of bombs dropped. For example, its often stated that 41,000 tons of bombs were dropped during the Blitz. This does not give a scale of how many bombs were dropped. Keep in mind that most of these would be 250 or 500kg high explosive weapons, with a rather large amount of incendiaries as well. But you've also got bigger 1,000kg mines as well. To give you an idea I posted this picture to my Facebook page a few weeks ago.
It is the bomb census data for the final quarter of 1941. If you look on the right hand page it gives you a number of UXB's by weight of bomb. In October alone, there were 100 UXB's and that isn't including smaller weapons like butterfly bombs or incendiaries. Each one of these had to be attended by a bomb disposal officer. Due to the bravery of these men, and other civilians during the period it was felt that existing medals and awards were insufficient. Thus, in September 1940, the George Cross medal was created.
Lt Andrews
The first award of a George Cross came on the 23rd of September 1940, technically the day before the medal was officially established. The recipient was Second Lieutenant Wallace Launcelot Andrews, for his actions on 26th of August 1940. Lt Andrews had been born in 1908 and was an architect before the war. He was called up in December 1939 and posted to the Royal Engineers. He was commissioned in January 1940. By August he was in command of a bomb disposal section when they were called to a UXB at Croham Hurst Golf Course, Croydon. The bomb was near the aerodrome. On closer inspection of the bomb it was found to have a new type of fuse, which was determined important and requested to be removed intact by the Department of Scientific Research (DSR). Hunched over the bomb Lt Andrews managed to get the fuse extracted about 1.5 inches, when it was pulled inwards by a spring or magnet. Several times attempts were made to pull the fuse, but each time the fuse was pulled back into place. Eventually Lt Andrews moved his section back to what he considered a safe distance, returned to the bomb and tied a string to the fuse discharger. He retired a short distance and gave the string a solid pull, attempting to rip the fuse assembly out of the bomb.
The bomb instantly exploded, hurling Lt Andrews through the air for some distance. Two of his men were also injured by splinters.

There are a great may stories of bomb disposal men working on bombs under incredible circumstances, such as Lieutenant Bertram Stuart Trevelyan Archer who worked on a bomb at the Anglo-Iranian oil storage facility in 1941. It had been hit by a stick of bombs that had all been duds. During the several hours he was working there two of the bombs detonated setting fire to the fuel storage, despite this Lt Archer continued his work.
There is also Doctor Arthur Douglas Merriman, a civilian. Dr Merriman was director at the DSR and would often attend extremely dangerous bombs and work on them. On the 11th of September 1940 at regent street London he attended a bomb. As work began on the bomb it was found impossible to remove the fuse, which then started ticking. This meant the clockwork on the bomb had been activated and after a pre-set, and unknown length of time the bomb would explode. Dr Merriman decided to remove as much of the explosive in the bomb as possible, this would limit the damage the bomb could do. The explosive was solid cast TNT which needed to be steamed to make it softer and pliable at which point it could be removed. As an example of how long this could last a previous bomb that had to be steamed empty had taken well over 12 hours (incidentally the Officer involved in that incident had also won the George Cross). In this case Dr Merriman worked on the bomb for four hours.
He judged the time and explosive perfectly, getting to safety seconds before the bomb exploded. The only damage the bomb caused, when it detonated, were some broken windows.
1000kg Luftmine
The incident that got me thinking about this subject were the actions of Lieutenant Harold Newgass. In November 1940 a 1000kg mine hit the gas works at Garston Gas Works in Liverpool. It was the same type of mine that was washed up earlier this year at Bognor Regis.
Lt Newgass' mine had hit a 4,000,000 cubic feet gas holder and passed through the roof. The parachute was entangled and keeping the mine suspended nose down.
The gas holder which had the mine stuck in it.
A quick explanation of how a gas holder works is in order to explain the situation. There is an island in the middle of the gas holder, this island has water around it allowing gas to be pumped into and out of the holder, with the water acting as a seal (a bit like the U-bend on a sink or toilet). The mine was in the center of the 65m wide holder and resting on the brick island next to one of the supports.
As the mine was inside a gas rich atmosphere no sparks could be allowed, so there was no form of illumination. Equally the atmosphere was such that a normal gas mask wouldn't work, and so Lt Newgass had to use breathing apparatus from the fire brigade, a piece of equipment he had no experience with. Finally, the fire brigade only had six bottles of air, each rated for thirty minutes. However, Lt Newgass would be using air much faster than normal due to the extreme exertion. Even just getting to the mine involved him wading through about 30m of waist, or even chest deep oily water. If he overestimated how long he had spent on the device there was no hope of him getting to safety quickly and he would be asphyxiated.
Lt Newgass
It took two days for Lt Newgass to defuse the bomb. The first three bottles of air were used on the first day to assess the situation, transport his equipment and secure and brace the mine. The second day he returned and encountered his first problem, the fuse access panel for the mine was resting against one of the steel supports for the gas holder. Lt Newgass had to rotate the mine, by hand, and if there was the slightest spark from the metal surfaces rubbing against each other, he and the surrounding area were going to vanish in a massive explosion.
No tragedy struck, and Lt Newgass was able to remove the fuse and detonators while using bottle number four. However, these mines also had a backup hydrostatic clock fitted. So, using his fifth cylinder of air Lt Newgass returned and removed the keep ring for this device, and rendered the bomb safe.

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