Royal Aircraft Factory S.E.5

The Royal Aircraft Factory S.E.5 was a British biplane fighter aircraft of the First World War.

The first examples reached the Western Front before the Sopwith Camel. Although it had a much better overall performance than the Camel, problems with its Hispano-Suiza engine, particularly the geared-output H-S 8B-powered early versions, meant that there was a chronic shortage of S.E.5s until well into 1918 and fewer squadrons were equipped with the S.E.5 than with the Sopwith fighter. Together with the Camel, the S.E.5 was instrumental in regaining allied air superiority in mid-1917 and maintaining it for the rest of the war, ensuring there was no repetition of "Bloody April" 1917 when losses in the Royal Flying Corps were much heavier than in the Luftstreitkräfte.

Design and development

The S.E.5 (Scout Experimental 5) was designed by Henry Folland, John Kenworthy and Major Frank Goodden of the Royal Aircraft Factory in Farnborough. It was built around the new 150 hp (112 kW) Hispano-Suiza 8 a V8 engine that, while providing excellent performance, was initially underdeveloped and unreliable. The first of three prototypes flew on 22 November 1916. The first two prototypes were lost in crashes (the first killing the chief test pilot at the Royal Aircraft Factory, Major F. W. Goodden on 28 January 1917) due to a weakness in their wing design. The third prototype underwent modification before production commenced; the S.E.5 was known in service as an exceptionally strong aircraft which could be dived at very high speed – the squarer wings also gave much improved lateral control at low airspeeds.