Short S.29 Stirling Mk.I
Been quite a while, but finally @raafif and @Imperialist's work on the Stirling gets to complete the RAF heavy bomber fleet. I intended to publish this set with the British overview of my AU, but thought better to get them out of the way now.
While Britain's other 4-engined heavy bombers were development of medium twins to specification P.13/36, only the Stirling was designed as a heavy bomber from the start, to specification B.12/36.
The final winner of the heavy bomber contract was Supermarine with their 316/317/318, while Shorts was given a contract for the "backup plan" for their S.29. In it's original form the aircraft was considered to be to close to a landplane version of the S.25 Sunderland (no record of the actual look of the original design appears to remain), and a significant redesign was required. With the death of designer Reginald Mitchell and the preoccupation with the Spitfire, work at Supermarine was slower than at Shorts, and so the prototype Stirling was the first to fly in May 1939. Then on 26 September 1940 the Luftwaffe had a major victory of the blitz by bombing the Supermarine factory and destroying the 2 prototype 317 bombers and all engineering tools and documentation. Britain's new heavy bomber was now dead, and Shorts' backup design was now thrust forward into full production.
To assist in development Shorts had constructed a half-scale model, the S.31, and its use was particularly important for the eventual design of the gangly undercarriage required due to the large size of the aircraft.
The first production aircraft were delivered in August 1940, and were very similar to the prototypes, with no dorsal turrets and propeller spinners. Then on 15 August the Luftwaffe struck the Shorts plant and destroyed 6 aircraft on the assembly line. Fortunately them damage was not as catastrophic as that on the Supermarine factory, but Stirling production was in initiated in Northern Ireland.
The initial belly dustbin turret was found problematic, often falling down while taxiing and creating too much drag when deployed in flight. The Mk.I Series II production dispensed with the turret, and subsequent models did not reintroduce one.
The 81st aircraft became the first of the Stirling Mk.I Series III aircraft, now fitted with a dorsal turret and the higher powered Bristol Hercules XI engines and exhaust flame dampeners.