Flying Forever - In-Flight Refuelling, World War 2

The British Air Ministry, having supported development of in-flight refuelling first by RAE then by Flight Refuelling Limited before WW.2, retained its interest when war broke out. A study was made in 1939 using a Short Stirling bomber, but no tests were conducted; further proposals over the next couple of years were considered impracticable for large scale operations by Air Staff and interest waned.

Plans were under consideration for airborne attacks on Japan in 1943, but there were no Allied bases near enough to bring the plans to fruition. The Air Ministry decided that conversion of the versatile Avro Lancaster to a tanker would offer a solution, and in February 1944 was prepared to authorise 50 sets of equipment for training and development. The vision of a Very Long Range bomber force of 500 bombers and an equal number of tankers to equip Tiger Force, was never achieved. Two prototype tanker and receiver Lancasters (PB972 and ND648) flew by November, but official enthusiasm was lacking, and during 1945 Pacific bases for Allied air operations became available in increasing numbers.

Some conversions were made, including the fitting of more sophisticated navigational apparatus for operations over large stretches of water. The impending production of the Avro Lincoln bomber, and potential to operate bombers in a state of "overload" with extra fuel, also played a part in reducing British enthusiasm. All the same, orders were actually issued to prepare a large number of Lancasters to act as tankers for the new Lincolns. Limited trials continued at the Bomber Command Development Unit during 1945, with Lancaster tankers ND574 and ND843, and receivers ND793 and ND991.

Other options to increase the fuel capacities of the Lancasters were also pursued, including additional 400 gallon tanks in the bomb bay and removal of the top turret to save weight. Two Lancaster Is were also tested with 1,200 gallon saddle tanks faired into the cockpit and extending back over the upper turret position. The aircraft were flown to India for trials, and made an appearance in Australia, but the tests were disappointing and both aircraft were scrapped in November 1946.

The Americans were, meanwhile, gearing up in early 1942 for retaliatory raids on Tokyo after the attack on Pearl Harbour. When that objective was achieved by Lt.-Col. Doolittle using other methods, development still continued. A set of British Flight Refuelling Ltd. equipment was fitted to a B-17E tanker (41-2539) and B-24D receiver (40-2353) by Pennsylvania Central Airlines, with Flight Refuelling Ltd. assistance. Tests conducted in April 1943 were successful, and tentative plans contrived for a raid to depart the Aleutians for Tokyo, its B-17s being refuelled by B-24 tankers. The bombers would carry on to land in China. The time to train crews and the advent of the B-29 ended the scheme.

Germany also tested airborne refuelling, with a hose-equipped Heinkel He.111 tanker and various types as receivers. The Ju.290 was put forward as a suitable tanker for use with its reconnaissance equivalent, and trials were conducted in 1944. Germany was becoming progressively isolated from its fuel supplies, and the shortage of resources until the war's end saw that the scheme did not progress.