 Further delays were caused by the extensive wind tunnel testing that was needed and the change from a Rolls-Royce Merlin to the more powerful Rolls-Royce Griffon.Also, the design specification was changed in 1944 to a new requirement, S.14/44 (later S.14/44/2) - the role of the aircraft being changed from ship-based reconnaissance and gunnery spotting to land-based Air-sea rescue.This change removed the four-gun turret the design had featured.