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Flown by Captain Ray Collishaw, one of the great Canadian aces of WW1.
From February to July 1917, one of the most unusual British fighters, the Sopwith Triplane, served in France. It had a short, but brilliant, career until it was superseded by the Sopwith Camel. During the six months that it flew, the triplane alarmed the Germans and drove their aviation industry to desperate measures to catch up.
Engine: 130 hp, Clerget 9B 9-cylinder air-cooled rotary
Wingspan: 26 ft. 6 in.
Length: 18 ft. 10 in.
Height: 10 ft. 6 in.
Weight: 1,541 lb.
Max. speed: 117 mph at 15,000 ft.
Ceiling: 20,500 ft.
Endurance: 2 hours
Armament: 1 machine gun
Crew: 1
Herbert Smith started design work on a triplane in late 1916, about the same time as the Blackburn triplane (a complete failure). The Sopwith prototype flew on March 29, 1917, and soon it generated great enthusiasm in British airmen, so that 400 were ordered. Ultimately, much of the order was cancelled as only the RNAS accepted the triplane. The navy’s units soon enjoyed their first successes, especially Canadian Ray Collishaw, who downed 7 enemy planes and damaged another 17 in May and June of 1917.
As the Camel came on line, the numbers of Triplanes diminished. By October, only one squadron was equipped with it. Production totaled 144.
Specifications from “Practical Aviation,†by Charles Hayward, 1919
The following data on the Sopwith are taken from a description of a captured machine which appeared in Flugsport and was later translated for publication in Flight, the British War Department not having permitted the publication of any specifications on this machine prior to that time. Its accuracy is accordingly not vouched for. The general dimensions and weights are an approximation to the Curtiss triplane.
Planes
The span of the three wings is the same, that is, 8.07 meters, with a chord of 1 meter, the lower and middle wings being attached to short wing sections on the fuselage, the upper wings are attached to an engine, or center, panel supported on struts rising from the body. Solid spars are used, front and rear, in the upper wing, the usual I-beam section being employed for the spars of the other wings. A single streamlined spruce interplane strut is used on either side of the body, while a pair of central struts rises from the rails of the fuselage to the upper wing.
In order to give a better view, the middle wing, which is on a level with the pilot’s face, is cut away. The construction just described applies to the Curtiss in most respects. Streamline wire about ¼ inch in diameter is used for the wing bracing. The landing wires are in the plane of the struts, while the bracing of the body struts, as well as the duplicate lift wires, carried forward to a joint just buck of the engine cowl. From the far spar of the middle wing, wires are carried fore and aft to the upper ils, or longerons, of the fuselage, while the lower wing also has a bracing wire curried to the lower longeron.
Ailerons interconnected by steel tapes are fitted on all three wings, celluloid windows being placed over the control cable pulleys for inspection purposes. The planes are staggered about 25 per cent, and have a small dihedral; the gap is 0.9 meter. The total lifting area is 27 square meters which, with a loaded weight of X kilos, gives a loading of only 25 kilos per square meter (a little Under 4 pounds per square foot), which accounts for its high speed and excellent climbing ability.
Tail Unit
The horizontal stabilizer, or fixed tail plane, is X meters wide and its angle may be varied in flight, this being a characteristic of all Sopwith machines. Attached to it is the two- part elevator, this as well as the rudder and vertical fin being of conventional design and construction. The latter is also true of the body, which is of square section, tapering to a vertical knife edge at the rear and rounding forward to fit the motor cowl.
Power Plant
A 110-h.p. Clerget rotary air-cooled motor drives A two-blade propeller and is fed with fuel by means of an air-driven plunger pump mounted on one of the struts. The loading per brake horsepower is 4.15 kilos, empty, and 5.85 kilos, fully loaded.
Landing Gear
The landing gear is the same as employed the Sopwith scout and “Spad” biplanes, consisting of twin V’s of steel tubing and a divided axle, the hinge of which is braced fron the fuselage.
Armament. The Sopwith triplane is built both as a single and as a two-seat machine and always carries a fixed machine gun placed above the fuselage and designed to fire through the propeller. When an observer is carried, a Lewis machine gun mounted on a turntable is also fitted.