Prior to achieving great success with the United States Army Eighth Air Force later in World War II, the Fortress had had an undistinguished baptism with the RAF. The first Fortress had flown in late July 1935 and after commencing deliveries to US Army squadrons, twenty B-17Cs were set aside for delivery to the RAF in May 1941. A single squadron as nominated to operate the aircraft – No 90 – which was to re-form at Polebrook in Northamptonshire.
After a short period working up, three Fortresses made their debut in a raid on Wilhelmshaven on 8 July 1941. Further missions saw the aircraft operated in daylight at altitudes up to 30,000ft to evade enemy fighters, but often flew alone. Consequently, success was very limited and many sorties had to be aborted as equipment (especially the guns) often froze at the higher altitudes. Within two months, the Fortresses had been taken off operations and transferred to the Middle East and Coastal Command where the aircraft’s long range did much to close the “Atlantic gap” – the middle of the Atlantic where few land based aircraft could reach and this subsequently meant that convoys were without air cover against U-Boats.
Two and a half years later, in February 1944, Fortresses again returned to the Bomber Command order of battle when No 214 Squadron began operations with B-17Gs (known as the Fortress III in the RAF) from Sculthorpe. The defensive firepower of the aircraft was a great improvement on the earlier Fortress Is with powered gun turrets in place of the manually operated positions of the earlier aircraft. No 214 Squadron, along with a second Fortress squadron, No 223 based at Oulthorpe, formed part of No 100 (Bomber Support) Group and their aircraft were fitted with a large number of electronic countermeasures to jam enemy radar sites.
Both squadrons were disbanded in July 1945, but a few Fortress IIIs remained with the RAF and were used as meteorological recce aircraft.