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The Blackburn Swift was a carrier based torpedo bomber developed during 1919, and which founded a long line of Blackburn biplane torpedo bombers that remained in service for the next twenty years. In 1917 the Admiralty had issued a specification for a torpedo bomber which had produced the Short Shirl and Blackburn Blackburd, but neither of these aircraft had proved satisfactory, and so late in 1919 the Air Ministry (which had taken over responsibility for Naval aviation) re-issued the specification.
Blackburn responded with the T.1 Swift, a private venture aircraft built in five months at the start of 1920. The Swift was designed by Major F. A. Bumpus, Blackburn’s chief designer and joint managing director. He had worked with Robert Blackburn during the First World War, and joined the company at the end of the war. The Swift was a two-bay biplane, with staggered folding wings (the first time this had been done on a British aircraft), built around a strong structure of steel tubes. It was equipped with a self-sealing fuel tank, an unusual feature for the period. The Swift had a divided undercarriage, which meant that the wheels did not have to be dropped to launch a torpedo.
The Swift had a rather unusual appearance. The pilot’s cockpit was just under the trailing edge of the upper wing. From the front of the cockpit to the engine the top of the fuselage sloped down steeply, before levelling out around the engine. The engine was a 450hp Napier Lion.
The prototype was complete enough to show at the Olympia Aero Show in July 1920, although with the torpedo launching equipment removed. The maiden flight was made later in the year, and was nearly a complete disaster. The centre of gravity of the aircraft was in the wrong place, and as a result there was no elevator control and the aircraft couldn’t be stopped from climbing. The test pilot managed to land the aircraft intact, and the problem was solved by sweeping the wings back by a few degrees. With this modification the aircraft made a more successful second flight.
On 23 December 1920 the first Swift I was delivered to the RAF for evaluation at Martlesham. Tests on land were completed by 9 May 1921, and the Swift was then passed to the navy for deck landings. The Swift attracted a number of export orders. The US Navy ordered two Swift Fs, two went to Japan and three to Spain. The biggest order came from Britain, where the type was ordered into production as the Blackburn Dart.
A number of further developments on the Swift was proposed, but probably never built. Amongst them was the Swift Mk IV, powered by a more powerful Lion engine, and with a greatly expanded fuselage to give room for three crew members. Although the Swift IV never materialised, a similar aircraft emerged as the confusingly named Blackburn Blackburn fleet spotter.
Engine: Napier Lion IB
Power: 450hp
Wing span: 48ft 6in
Length: 17ft 6in
Height: 12ft 3in
Tare weight: 3,550lb
All-up weight: 6,300lb
Maximum speed: 106mph
Service ceiling: 15,000ft
Range: 350 miles