No. 1 Naval Squadron became fully operational with the Triplane by December 1916, but the squadron did not see any significant action until February 1917, when it relocated from Furnes to Chipilly. No. 8 Naval Squadron received its Triplanes in February 1917. Nos. 9 and 10 Naval Squadrons equipped with the type between April and May 1917. The only other major operator of the Triplane was a French naval squadron based at Dunkirk, which received 17 aircraft.
The Triplane's combat debut was highly successful. The new fighter's exceptional rate of climb and high service ceiling gave it a marked advantage over the Albatros D.III, though the Triplane was slower in a dive. The Germans were so impressed by the performance of the Triplane that it spawned a brief triplane craze among German aircraft manufacturers. Their efforts resulted in no fewer than 34 different prototypes, including the Fokker V.4, prototype of the successful Fokker Dr.I.
The Triplane was famously flown by No. 10 Naval Squadron's "B" Flight, better known as "Black Flight." This all-Canadian flight was commanded by the ace Raymond Collishaw. Their aircraft, named Black Maria, Black Prince, Black George, Black Death and Black Sheep, were distinguishable by their black-painted fins and cowlings. Black Flight claimed 87 German aircraft in three months while equipped with the Triplane. Collishaw himself scored 34 of his eventual 60 victories in the aircraft, making him the top Triplane ace.
Withdrawal from service
For a variety of reasons, the Triplane's combat career was comparatively brief. In service, the Triplane proved difficult to repair. The fuel and oil tanks were inaccessible without substantial disassembly of the wings and fuselage. Even relatively minor repairs had to be made at rear echelon repair depots. Moreover, spare parts became difficult to obtain during the summer of 1917, and No. 1 Naval Squadron's complement was reduced from 18 to 15 aircraft.
The Triplane also gained a reputation for structural weakness because the wings sometimes collapsed in steep dives. This defect was attributed to the use of light gauge bracing wires in the 46 aircraft built by subcontractor Clayton & Shuttleworth. Several pilots of No. 10 Naval Squadron used cables or additional wires to strengthen their Triplanes. In 1918, the RAF issued a technical order for the installation of a spanwise compression strut between the inboard cabane struts of surviving Triplanes. One aircraft, serial N5912, was fitted with additional mid-bay flying wires on the upper wing while used as a trainer.
Another drawback of the Triplane was its light armament. While contemporary Albatros fighters were armed with two guns, most Triplanes were armed with a single synchronised Vickers machine gun. Efforts to fit twin guns to the Triplane met with mixed results. Clayton & Shuttleworth built six experimental Triplanes with twin guns. Some of these aircraft saw combat service with Nos. 1 and 10 Naval Squadrons in July 1917, but performance was reduced and the single gun remained standard. Triplanes built by Oakley would have featured twin guns, an engineering change which severely delayed production.
In June 1917, No. 4 Naval Squadron received the first Sopwith Camels and the advantages of the sturdier, better-armed fighter quickly became evident. Nos. 8 and 9 Naval Squadrons transitioned to the Camel between early July and early August 1917. No. 10 Naval Squadron converted in late August, turning over its remaining Triplanes to No. 1 Naval Squadron. No. 1 operated Triplanes until December, suffering heavy casualties as a consequence. By the end of 1917, surviving Triplanes were used as advanced trainers with No. 12 Naval Squadron.