Operation Pluto

Operation Pluto was a Second World War operation by British engineers, oil companies, and the British Armed Forces; to construct undersea oil pipelines under the English Channel between England and France in support of Operation Overlord, the Allied invasion of Normandy in June 1944. According to the Official History, PLUTO originally stood for 'Pipe-Line Underwater Transportation of Oil'.

The scheme was developed by Arthur Hartley, chief engineer with the Anglo-Iranian Oil Company. Allied forces on the European continent required a tremendous amount of fuel. Pipelines were considered necessary to relieve dependence on oil tankers, which could be slowed by bad weather, were susceptible to German submarines, and were also needed in the Pacific War. Geoffrey William Lloyd, the Secretary for Petroleum, in 1942 met Admiral Mountbatten, Chief of Combined Operations, whose area this was, and then the Chairman of Anglo-Iranian. Hartley's idea of using adapted submarine telephone cable was adopted.

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