Petroleum Warfare Department

The Petroleum Warfare Department (PWD) was an organisation established in Britain in 1940 in response to the invasion crisis during World War II, when it appeared that Germany would invade the country. The department was initially tasked with developing the uses of petroleum as a weapon of war and it oversaw the introduction of a wide range of flame warfare weapons. Later in the war, the department was instrumental in the creation of the Fog Investigation and Dispersal Operation (commonly known as FIDO) that cleared runways of fog allowing the landing of aircraft returning from bombing raids over Germany in poor visibility; and Operation Pluto which installed prefabricated fuel pipelines between England and France soon after the Allied Invasion of Normandy in June 1944.

At the beginning of World War II, in September 1939, there was little fighting in the West until the German invasion of France and the low countries in May 1940. Following the fall of France and the withdrawal of the British Expeditionary Force (BEF) from the beaches at Dunkirk in June 1940, Britain was threatened with possible invasion by German armed forces in 1940 and 1941.

In response to this threat of invasion, the British sought to expand the Royal Navy, Royal Air Force, and Army and to replace the equipment that had been left behind at Dunkirk. Also, to supplement the regular armed services with volunteer organisations such as the part-time soldiers in the Home Guard. With many types of equipment in short supply, there were frantic efforts to develop new weapons – particularly those that did not require scarce materials.

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