In August 1934, the US Army Air Corps specified the need for a large multi-engine bomber capable of carrying a “useful bomb load” at an altitude of 10,000 ft with a top speed of at least 200 mph. A Boeing design team immediately set to work in Seattle and the prototype B-17 (designated Model 299) flew for the first time on 28th July 1935, less than 12 months later, with chief test pilot Les Tower at the controls. When rolled out bristling with machine gun installations, a reporter from the Seattle Times referred to the aircraft as a ‘flying fortress’, a name quickly trademarked by Boeing.
Development continued and, although the prototype Model 299 was destroyed in an accident in October 1935, the USAAC was already impressed by the machine’s apparent capabilities and ordered 13 for service testing. The first 12 were delivered in March 1937 and, following evaluation, more aircraft were ordered with the first operational machine entering service on 31st January 1939 as the B-17A. Whilst fewer than 200 aircraft were in service with the USAAC at the time of the attack on Pearl Harbour, production quickly accelerated thereafter.
The Flying Fortress first saw combat in 1941 with the acquisition of 20 B-17Cs by the RAF for high altitude missions. In August 1942, the now US Army Air Force began operations from bases in the UK with the B-17E, the first mass-produced model. Each new variant was more heavily armed than its predecessor with the ultimate B-17G deploying 13 x .5in Browning machine guns. Although this particular version was capable of a 12,800 lb bomb load, the Flying Fortress rarely flew combat missions with more than 5,100 lb.
A particular attribute of the B-17 was its ability to take punishment and return home after sustaining major battle damage. That said, its losses on daylight operations over the Continent were severe. Some 4,750 of the 12,731 machines built were lost in combat and given a standard aircrew complement of 10 personnel, human losses were also considerable. Over 50 Flying Fortresses survive today with a dozen or so in airworthy condition. The UK’s sole airworthy B-17 – the ‘Sally B’ – is maintained at the .Imperial War Museum, Duxford.
RAF Tangmere’s association with the Flying Fortress stems from its role as an emergency airfield for battle-damaged machines limping back over the Channel. It was one of Tangmere’s Advanced Landing Grounds, Apuldram that became the centre of attention in June 1943, however, when a damaged B-17 landed there with the actor Clark Gable on board as a member of the crew.