In January 1918, the Admiralty issued specification N.1B, seeking an aircraft to replace the Sopwith Cuckoo torpedo bomber.

While the Cuckoo was successful, it could only carry a 1,000 lb (450 kg) Mark IX torpedo, which was not believed to be powerful enough to sink large armoured warships.

The specification therefore required an aircraft capable of carrying a 1,436 lb (651 kg) Mark VII torpedo, which had a much larger warhead.

[1] In response, Harris Booth designed the Blackburd, a large, three-bay biplane with unswept, unstaggered wings and a slab-sided fuselage.

[2] The Blackburd's simple lines were designed to facilitate rapid production and the wings were able to fold backwards to allow storage in a ship's hangar.