The Short Stirling was the first of RAF Bomber Command's trio of four-engine heavy bombers that mounted the great night offensive over Europe during the last four years of the war, and the only one conceived from the outset as a four-engine aircraft. Designed to a 1936 specification, the Stirling was initially flown as a half-scale prototype in 1938, this being followed by the fullsize prototype which was destroyed on its first flight in May 1939, Production deliveries were first made to No. 7 Squadron in August 1940 (at the height of the Battle of Britain) and the Stirling Mk I flew its first operation on 10-11 February 1941. The type first bombed Berlin two months later. The Stirling Mk I of which 756 were produced, was powered by Hercules XI radiais, but the Stirling Mk II with Wright Cyclones did not progress beyond the prototype stage, The Stirling Mk III was powered by Hercules XVIs and, with 875 built (plus many Mk Is converted) constituted the main bomber variant; it also introduced the two-gun dorsal turret. Stirlings were the first operational aircraft to carry the original form of Oboe1 navaid in 1941, and in August 1942 took part in the first Pathfinder operations. Two posthumous VCs were won by Stirling pilots (Flight Sergeant R. H. Middleton of No. 149 Squadron and Flight Sergeant A. L Aaron of No. 218 Squadron), both during raids on northern Italy. By 1944 the Stirling Mk III was obsolescent, and flew its last raid in September that year. The Stirling Mk IV (of which 577 were built) was a transport/glider tug without nose and dorsal turrets, and was widely used on operations by the airborne forces during the last year of the war. The Stirling Mk V transport (160 built), without armament, joined the RAF in January 1945, Stirling bombers equipped 15 squadrons.
Specification Short Stirling Mk III
Type: seven- or eight-crew night heavy bomber
Powerplant: four 1,650-hp (1231-kW) Bristol Hercules XVI radial piston engines
Performance: maximum speed 435 km/h (270 mph) at 4420 m (14,500ft); service ceiling 5180 m (17,000 ft); range with 6350-kg (14,000 Ib) bombload 949 km (590 miles)
Weights: empty 19596 kg (43,200 lb); maximum take-off 31790 kg (70,000 lb)
Dimensions: span 30.20 m (99 ft 1 in); length 26.50 m (87 ft 3 in); height 6.93 m (22 ft 9 in); wing area 135,6 m2 (1,460.0 sq ft)
Armament: two 7.7-mm (0.303-m) machine-guns in each of nose and dorsal turrets, and four 7.7-mm (0.303-in) guns in tail turret, plus a maximum bombload of 6350 kg (14,000 lb)