The Firebrand required significant effort by Blackburn to produce a useful aircraft and the first discussions on a redesign of the aircraft with a laminar-flow wing took place in September 1943. The new wing was estimated to reduce the weight of the wing by and increase the aircraft speed by . The extent of redesign increased and this led to a new fuselage and other improvements. In October 1943, Blackburn's design staff, led by G.E. Petty, started work on this development of the Firebrand which led to Specification S.28/43 being issued by the Air Ministry on 26 February 1944 covering the new aircraft. The specification was designed around a Bristol Centaurus 77 radial engine with contra-rotating propellers that allowed the size of the rudder to be reduced.