Mid-20th Century Military Bridging (1920's - 1945)

Sir Donald Bailey

At the very end of the war a permanent home was established at Christchurch, Dorset for all things bridging. It was intended to form three RE Tank Bridging Battalions but plans changed as the war ended and the Experimental Bridging Company (later the Experimental Bridging Establishment: EBE) was formed from one of these Battalions under the command of Major G le Q Martel DSO MC RE who went on to play a signal role in military bridging reaching the rank of Lieutenant-General.

The pace of development slackened in the inter war period and equipment developed included amongst others the Canal Lock Bridge, the Inglis Assault Bridge, the Large Box Girder Bridgeand later the Small Box Girder Bridge, the Inglis Heavy Floating Bridge, the Mark IV pontoon, the Mark V trestle, the Folding Boat Equipment - see illustration 10, and the Christchurch Crib. This was a skeleton steel double cube measuring 6' x 3' x 3' used to make temporary bridge piers. Inglis continued to play a role in the development of bridging but was based at the University of Cambridge.

Sir Donald Bailey, KT, OBE (1901-85), designer of the Bailey bridge.

Donald Bailey joined the EBE in 1928 as a civilian designer. It is suggested that the idea of the Bailey Bridge - see illustration 9a, 9b, 9c, was sketched out on the back of an envelope in 1940 as Donald Bailey and others from the EBE returned from the loading trial of a new Inglis Bridge prototype in Cambridge. The EBE's requirement was for an easily manufactured steel bridge whose basic components would each weigh no more than a 6 man lift (600lbs), fit into a 3 ton GS lorry.

It had to be sufficiently flexible to be used over a wide range of gaps, with various loads and with pontoons. Bailey drew together the various threads of past developments and proposed a prefabricated K braced panel with male/female couplings and panel pins. Each panel was about 10 ft x 5 ft and had 18' cross girders. The through section was almost 13 ft with a 10 ft 9" roadway. The cross girders extended outside the panels and were used to support walkways. Panels could be added in parallel to form double and triple trusses. Panels could also be laid in layers up to 3 high. A 150 ft triple-triple bridge could carry a Churchill tank on its transporter (about 70 tons).

The simplicity of Bailey's design enabled mass production and some 700,000 panels were produced representing about 350 miles of bridging. The original design was adapted to make a pontoon bridge, a suspension bridge (longest built was 450 ft) and a multi-span bridge. There is no doubt that the Bailey Bridge in its various guises played a very significant role in all theatres of the war. In North West Europe alone some 1,500 bridges totalling over 29 miles of fixed and 3 miles of floating bridges were constructed. The longest was the 'Sussex Bridge' at 1,940 ft one of several built for the Rhine crossing. Sir Donald Bailey (knighted in 1946) continued to play a major role at Christchurch until 1962 when he was appointed Dean of the Royal Military College of Science (RMCS).