Editing Sopwith 1½ Strutter (section)

==Design and development==
[[File:An aeroplane leaving the deck of the Australia on a reconnaissance trip (13960807682).jpg|thumb|Sopwith 1 1/2 Strutter biplane aircraft taking off from a platform built on top of HMAS ''Australia'''s midships 'Q' turret. 1918]]
In December 1914, the [[Sopwith Aviation Company]] designed a small, two-seat biplane powered by an {{cvt|80|hp}} [[Gnome Engine Company|Gnome]] [[rotary engine]], which became known as the "Sigrist Bus" after [[Fred Sigrist]], the Sopwith works manager. The Sigrist Bus first flew on 5 June 1915 and although it set a new British altitude record on the day of its first flight, only one was built, serving as a company runabout.<ref name="Bruce RFC p499">Bruce 1982, p. 499.</ref><ref name="Jarrett database p56">Jarrett 2009, p. 56.</ref>

The Sigrist Bus formed the basis for a new, larger, fighter aircraft, the Sopwith LCT (Land Clerget Tractor), designed by [[Herbert Smith (aircraft designer)|Herbert Smith]] and powered by a {{cvt|110|hp}} [[Clerget]] engine. Like the Sigrist Bus, each of the upper wings (there was no true centre section) was connected to the [[fuselage]] by a pair of short (half) struts and a pair of longer struts, forming a "W" when viewed from the front; this giving rise to the aircraft's popular [[nickname]] of the {{frac|1|1|2}} Strutter.<ref name="bomber-40"/> The first prototype was ready in mid-December 1915, undergoing official testing in January 1916.<ref name="Jarrett database p56"/><ref name="Bruce I p544">Bruce 28 September 1956, p. 544.</ref>

The {{frac|1|1|2}} Strutter was of conventional wire-braced, wood and fabric construction. The pilot and gunner sat in widely separated tandem cockpits, with the pilot in front, giving the gunner a good field of fire for his [[Lewis gun]]. The aircraft had a variable-incidence [[tailplane]] that could be adjusted by the pilot in flight and [[air brake (aircraft)|airbrakes]] under the lower wings to reduce landing distance.<ref name="Bruce RFC p499"/><ref name="Jarrett database p56,8">Jarrett 2009, pp. 56, 8.</ref>

[[File:Sopwith Strutter RAFM.jpg|thumb|A preserved Sopwith {{frac|1|1|2}} Strutter at the RAF Museum, London, showing the W-form pairs of "{{frac|1|1|2}}" struts that gave the aeroplane its name, and the centrally-mounted Vickers machine gun]]
The Vickers-Challenger [[Synchronization gear#The Vickers-Challenger gear|synchronisation gear]] was put into production for the [[Royal Flying Corps]] (RFC) in December 1915 and in a few weeks, a similar order for the [[Synchronization gear#The Scarff-Dibovski gear|Scarff-Dibovski]] gear was placed for the RNAS.<ref name="Bruce I 543">Bruce 28 September 1956, p. 543.</ref><ref name="BruceII p586">Bruce 5 October 1956, p. 586.</ref> Early production {{frac|1|1|2}} Strutters were fitted with one or the other of these gears for the fixed [[.303 British|.303]]-in [[Vickers machine gun]]; due to a shortage of the new gears some early aircraft were built with only the observer's gun. Later aircraft were either fitted with the [[Synchronization gear#The Ross and other "miscellaneous" gears|Ross]] or the [[Synchronization gear#The Sopwith-Kauper gear|Sopwith-Kauper]] gears.<ref name="Bruce British p542">Bruce 1957, p. 542.</ref> No early mechanical synchronisation gear was reliable and it was not uncommon for propellers to be damaged or shot away.

The [[Scarff ring]] mounting was also new and production was at first slower than that of the aircraft requiring them. Various makeshift Lewis mountings as well as the older Nieuport ring mounting, were fitted to some early {{frac|1|1|2}} Strutters as a stopgap.<ref name="Bruce British p542-3">Bruce 1957, pp. 542–543.</ref>  The two-seaters could carry four {{cvt|25|lb}} bombs underwing, which could be replaced by two {{cvt|65|lb}} bombs for anti-submarine patrols.<ref name="Jarrett database p59">Jarrett 2009, p. 59.</ref> From the beginning, a light bomber version was planned, with the observer's cockpit eliminated to allow more fuel and bombs to be carried in the manner of the [[Martinsyde Elephant]] and the [[Royal Aircraft Factory B.E.12|B.E.12]], with an internal bomb bay capable of carrying four {{cvt|65|lb}} bombs.<ref name="Jarrett database p59"/><ref name="bruce wind2 p6">Bruce 2000, p. 6.</ref>