The Royal Aircraft Factory S.E.5 is a British biplane fighter aircraft of the First World War.
It was developed at the Royal Aircraft Factory by a team consisting of Henry Folland, John Kenworthy and Major Frank Goodden.
It was one of the fastest aircraft of the war, while being both stable and relatively manoeuvrable.
In most respects the S.E.5 had superior performance to the rival Sopwith Camel, although it was less immediately responsive to the controls.
Problems with its Hispano-Suiza engine, particularly the geared output H-S 8B powered early versions, meant that there was a chronic shortage of the type until well into 1918.
Thus, while the first examples had reached the Western Front before the Camel, there were fewer squadrons 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.
The S.E.5s remained in RAF service for some time following the Armistice that ended the conflict, some were transferred to various overseas military operators, while a number were also adopted by civilian operators.
The S.E.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 Frank 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.
Like the other significant Royal Aircraft Factory aircraft of the war (B.E.2, F.E.2 and R.E.8) the S.E.5 was inherently stable, making it an excellent gunnery platform, but it was also quite manoeuvrable.
It was one of the fastest aircraft of the war at 138 mph (222 km/h), equal at least in speed to the SPAD S.XIII and faster than any standard German type of the period.
While the S.E.5 was not as agile and effective in a tight dogfight as the Camel it was much easier and safer to fly, particularly for novice pilots.
First production version.
Single seat fighter biplane, powered by a 150 hp (112 kW) Hispano-Suiza 8a piston engine.
Improved production version, powered by a 200 hp (149 kW) Hispano-Suiza 8B, 8Ba or 8Bb V-8 (early version) or 200 hp (149 kW) Wolseley Viper piston engine.
Experimental prototype, with sesquiplane wings, streamlined nose and retractable radiator.
S.E.5a assembled from spare parts by American company Eberhart Aeroplane, 180 hp Wright-Hispano E engine and plywood-covered fuselages.
Drawings for a two seat fighter described as “based on a scaled-up S.E.5” were prepared early in 1917, the type was to have had a 31-foot 3-inch wingspan, 200 hp Hispano-Suiza 8 engine, and to have been armed with a single forward firing Vickers and a Scarff mounted Lewis for the observer.
Six examples ordered, because of the success of the Bristol fighter and in view of the shortage of Hispano-Suiza engines, none was ever completed.
20 ft 11 in (6.38 m)
26 ft 7 in (8.10 m)
60 in (1.52 m)
26 ft 7 in (8.10 m)
60 in (1.52 m)
9 ft 6 in (2.90 m)
244 sq ft (22.7 m2)
1,410 lb (640 kg)
1,935 lb (878 kg)
Max take-off weight
1,988 lb (902 kg)
60 in (1.5 m)
1 × Hispano-Suiza 8
Wolseley Viper water cooled V8 engine,
150 hp (110 kW)
2 or 4 bladed fixed pitch wooden propeller,
7 ft 9 in (2.36 m) diameter
138 mph (222 km/h, 120 kn)
300 mi (480 km, 260 nmi)
17,000 ft (5,200 m)
7.93 lb/sq ft (38.7 kg/m2)
1 x .303 in (7.7 mm) forward firing Vickers machine gun with Constantinesco interrupter gear
1 x .303 in (7.7 mm) Lewis gun on Foster mounting on upper wing
4 x 25 lb (11 kg) Cooper bombs, two under each lower wing, to be dropped in 2, 3, 4, 1 order.