The Grahame-White Factory is located in the grounds of the Royal Air Force Museum, London. As well as being an iconic building, from the very earliest age of industrialized aircraft construction, it is also home to a magnificent collection of World War One aircraft and paraphernalia. Some of the aircraft on display are originals, some reproductions (many of which incorporate original parts, such as engines) but whatever their origin, the whole collection is quite splendid, and does an excellent job of portraying the earliest days of military flying.
The Sopwith Aviation Company Ltd, ably directed by Sir Thomas Sopwith, had produced some of the classic British fighting aircraft of the early part of WW1. The Royal Flying Corps had benefitted from the bombing and ‘fighting’ qualities of the Sopwith One and a Half Strutter (see previous piece on this aircraft), and the light and handy Sopwith Pup ‘scout’, but the company wanted something that was better than anything the Germans could field. In 1916, Sopwith’s Chief Engineer, Herbert Smith, was instructed to construct a new ‘scout’ as a private venture, one that would give its pilot the maximum view, allied with superior rate of climb and excellent manoeuverability. The resulting aircraft turned out to be a triplane, as Smith thought that three shorter, narrower cord wings (each wing with its own aileron), would give a better rate of climb, and a faster roll rate; a variable incidence tailplane enabled the aircraft to be trimmed to fly ‘hands off’. By positioning the middle wing level with the top of the fuselage, the pilot had an excellent view directly ahead, and by putting rectangular cut-outs alongside the fuselage, the view forward and downward over the lower wing was acceptable. The gap between the mainplanes was larger than in a biplane, which also increased visibility for the pilot, and there were a minimum of bracing wires. An unusual arrangement was the fact the interplane struts were made in one piece, and passed through a slot in the middle wing. Power came from a 9-cylinder Clerget 9Z of 110hp. ‘N500′, the prototype of the newly named Sopwith Triplane, first flew on 28 May, 1916, in the capable hands of the famous Australian aviator and Sopwith’s Chief Test Pilot, Harry Hawker. To the astonishment of all the onlookers, Hawker pulled the little triplane into THREE loops, hardly the norm for a first flight of a prototype! The initial climb rate of over 1,000 ft/min was outstanding for the day, and was better than any German aircraft in existence. The Royal Naval Air Service placed orders for 95 Triplanes with Sopwith, and 46 with the subcontractor Clayton & Shuttleworth, and another contract for 25 with Oakley & Co, a new company, formed on the site of a former roller-skating rink, who had absolutely NO experience at building aircraft! The Royal Flying Corps was also impressed with the Triplane, and ordered 106 from Clayton & Shuttleworth, as well.
The squadrons of the Royal Naval Air Service were heavily engaged on the Belgian and French coasts, and the left flank of the Western Front. The Battle of the Somme, in which more than 600,000 Allied soldiers were either killed or wounded during the period July – November, 1916, had left the RNAS squadrons severely depleted. The Admiralty made a deal with the RFC – they would take over the RFC’s Clayton & Shuttleworth contract in exchange for an equal number of SPAD VII fighters on order by the Admiralty; the deal was done, and ‘N500′ was sent to Dunkirk, France to be tested by ‘A’ Naval Squadron, No. 1 Naval Wing. The pilots were unanimous in their praise for the ‘Tripehound’ as it became known, and the type was rushed into service with No. 1, 8, 9 and 10 Squadrons, RNAS, and immediately established superiority over the German squadrons equipped with the Albatros D.III. Later production versions of the Triplane were equipped with the Clerget 9D of 130hp, which gave it a ceiling of over 20,000 ft and a top speed of 117 mph. Despite the fact that the Tripe could break off combat at will by climbing away, it could not dive as fast as the Albatros, and there were some nasty losses due to Triplanes breaking up in the air. This was traced to thinner than normal bracing wires being used by Clayton & Shuttleworth, and these were supplemented by more wires, as well as a cross brace being fitted between the fuselage cabane struts.
The Triplane was used on the Western Front only by the RNAS, as well as a handful which were sent to the French Centre d’Aviation Maritime, from December 1916 to January 1917. The Triplane was so superior to the current German ‘scouts’ that Anthony Fokker, the well-known designer of German fighter aircraft, carefully examined the crashed remains of one, and literally dozens of triplane prototypes were built by multiple German aircraft factories. Fokker’s Dr.1 Triplane could have said to have been influenced by the Sopwith design. Some units became very proficient on the Tripe. For example, ‘B’ Flight, of No. 10 Squadron RNAS (an all-Canadian unit), the famous ‘Black Flight’ – who named their aircraft Black Maria, Black Death, Black Sheep, Black Prince, and Black Roger and painted them mostly black – established an amazing record. Under their Flight Commander, Raymond Collishaw, the Canadian ace, the five members of ‘B’ Flight shot down 87 aircraft from May to July, 1917. Collishaw went on to score 34 of his 60 victories on the Sopwith Triplane, becoming the leading Triplane ace. The Triplane had certain engineering problems; due to its complex wooden structure, both the fuel and the oil tanks were relatively inaccessible, and repairs to these items required the aircraft to be returned to a repair depot, where it had to be partially dismantled to undertake the work.
By late 1917, the Triplane had become outmoded. Its single Vickers .303″ machinegun was not enough to combat the standard German fighter armament of 2 x 7.9 Parabellum machineguns, and attempts to fit twin Vickers were not really successful. Indeed, the Oakley contract for 25 Triplanes was cancelled after only three were built – they were due to have twin Vickers. Another Sopwith fighter, the new Camel, began replacing Triplane in late 1917, and survivors were withdrawn to the U.K. were they were used for training purposes. The whole of the ex-RFC contract for 105 machines with Clayton & Shuttleworth was cancelled; this was rather odd, as this was the contract that the Admiralty had swapped for the same number of SPAD VIIs!
One last attempt was made by Sopwith to revive the triplane formula. Two examples of a triplane design, based mostly on the Sopwith One and a Half Strutter and powered by the 200hp V-8 Hispano-Suiza liquid-cooled engine were constructed, but they proved to be a failure.
One of the three aircraft built in October 1917 by Oakley and Co. Ltd, was delivered to the RFC at Hendon, on the outskirts of London. N5912 saw no combat, and was then sent direct to No. 2 School of Aerial Fighting & Gunnery at Marske, near Redcar in Yorkshire. At the end of the war, it formed part of the very first public exhibition staged by the new Royal Air Force, at No. 9 Aircraft Acceptance Park on Town Moor Airfield, Newcastle-upon-Tyne, from 12 February to 15th July, 1919. This event was repeated at Roundhay Park in Leeds. A long period in storage at various RAF Stations then following, before it wound up in the basement of the Science Museum, London, along with an RE8, Fokker D.VII and several other WW1 types, which were expected to form the core of an Imperial War Museum Exhibition. By now it was in very poor condition, and most people were amazed when it was decided (after it was nearly burnt on the fire-dump at RAF Cardington) to restore it to flyable condition. This was done by Flight Lieutenant Buckle in 1936, and the Tripe was flown in the RAF Pageant that year at Hendon, as part of a simulated attack on an enemy observation balloon; the display was repeated the following year. During WW2, the aircraft was stored, but again, was nearly scrapped post-war. It was renovated at No.15 MU, Wroughton (a place were I worked), and earmarked for the new RAF Museum. In 1964, it was sent to the Fleet Air Arm Museum, as part of a special exhibition by the Royal Navy to mark RNAS Triplane Operations.
Finally, in 1971, N5912 arrived at the RAF Museum, Hendon. After removing several non-standard components and undergoing more remedial work, the Triplane (one of only two original machines left – the other being in the Central Air Force Museum, in Monino, Russia) was placed in the Grahame-White Factory, Hendon, becoming part of one of the most comprehensive collections of WW1 aircraft in the world.
The Sopwith Triplane, for a time, one of the most effective fighter aircraft in the world.