Designed by the Short Brothers, who better known for their four engined Sunderland flying boat. The Stirling was Shorts' response to the Air Ministry specification B.12/36 requesting designs for a four engined heavy bomber. And was destined to be the first of the Bomber Commands three heavy bomber aircraft types to enter service during the Second World War.

However, even before Arthur Gouge, the aircrafts' designer began work, he was faced with a major restriction in that the wing span could not exceed 100 feet. This dimension being the maximum door size of the hangers currently in use. This imposed limitation caused him to adopt a low-aspect wing ratio, which also included a number of the Sunderland's features. The result of which caused the aircraft to have poor high-altitude performance and a restricted operating ceiling when fully loaded.

The first prototype (L7600) flew on May 14, 1939, but crashed while landing from this flight. It was not until December of the same year that the second prototype (K7605) was ready for flight trails.

These trails soon exposed the Stirlings' limitations, but at the time, these were not considered serious. The Air ministry being mainly more interested in replacing the existing, Hampden and Whitley medium bombers with the new four engine heavies.

By August 1940, No. 7 Squadron, RAF stationed at Leeming had replaced their Hampden's, with the new Stirling Mk.I. By doing so, they increased their bomb lifting capability from 4,000 lbs. (1,814 kg) to 14,000 lbs. (6,350 kg) per aircraft. An increase of 350 percent. The squadron would also take the aircraft on its first operational sorties against Rotterdam on February 10/11, 1941.

The Stirlings' bomb bay arrangement, which consisted of a neat system of cells in the fuselage, also became another restriction to the aircraft usefulness. As this set up prevented the aircraft from carrying bombs over the 4,000 lbs. (1,814 kg) in size. Whilst this was still was a significant sized bomb; by the wars end larger bomb designs had entered service. None of which could be carried by the aircraft.

As No. 3 Groups' squadron's were re-equipped. They began to undertake a wider range of targets including substantial amounts of daylight operations over France. And it was during these early months of 1941, that the aircraft achieved a reasonable reputation for being able to withstand battle damage and in its self-defense capabilities. The remainder of 1941 proved to be a good year for the Stirling, as it attacked targets in Germany, Italy and as far away as Czechoslovakia. December 1941, also saw it become the first Bomber Command aircraft type to be fitted with the new navigational aid "Oboe".

As 1942 progressed, No. 7 squadron along with its Stirling's an other Bomber Command squadrons. Were transferred to form the nucleus of the newly formed No. 8 (Pathfinder) Group. By the end of the year, the new Mk.III Stirling's, equipped with 1,650 hp Bristol Hercules XVI engines and a new dorsal turret design, were entering service and slowly replacing the Mk.I's.

By late 1943 however, the German defenses especially flak, proved to be the straw that broke the camels back. Whereas, the higher flying Halifax and Lancaster types, were somewhat immune to flak, but still had to contend with determined attacks by fighters. The Stirling mainly due to its low ceiling caused by its restricted wing span, began to suffer the highest losses amongst attacking aircraft. It was soon evident that such losses could not continue and Air Marshal Harris, was forced to withdraw the aircraft from operations. By early 1944, as supplies of the Avro Lancaster became available, most of the Stirling squadron's began to re-equipped with this type. Although, it would not be until September 8, 1944 that No. 149 squadron, flew last operation Stirling sorties against Le Havre.

This was however, not the end of the service life of the Stirling. With No. 100 (Bomber Support) Group, it would continue to carry out Radio Counter Measure sorties and dropping supplies to the resistance groups. And in the form of the Mk.IV it would serve with distinction as a paratroop carrier and glider-tug during the D-Day and again over Arnhem. Its final claim to fame was as the Mk.V where it continued to fly as a transport aircraft until the middle of 1946.

Of the bomber variants, a total of 712 Mk.I's and 1,047 Mk.III's were built.

Stirling Mk.III Data

Crew : Seven or eight

Span : 99'-1" (30.20 m)

Length : 87'-3" (26.59 m)

Weight : 22'-9" (6.93 m )

Empty Weight : 46,900 lbs. (21,274 kg)

Loaded Weight : 70,000 lbs. (31,752 kg)

Maximum Speed : 270 mph at 14,500 ft. (4,420 m)

Ceiling : 17,000 ft. (5,182 m)

Range : 590 miles (949 km) with 14,000 lbs. (6,350 kg) of bombs.

2,000 miles (3,219 km) with 3,500 lbs. (1,588 kg) of bombs.

Armament:

Two 0.303" machine guns mounted in both the front and dorsal turrets. Four 0.303" machine guns in the rear turret. \

Maximum bomb load 14,000 lbs. (6,350 kg)

Bomber Command Squadrons equipped with the Stirling.

7, 15, 75, 90, 149, 171, 196, 199, 214, 218, 513, 620, 622, 623