Sopwith Triplane

infobox Aircraft
name = Sopwith Triplane
type = Fighter
manufacturer = Sopwith Aviation Company



caption =
designer = Herbert Smith
first flight = 28 May 1916
introduction = December 1916
retired =
status =
primary user = Royal Naval Air Service
more users =
produced =
number built = 147 Bowers and McDowell 1993, p. 63.]
unit cost =
variants with their own articles = The Sopwith Triplane was a British single seat fighter aircraft designed and manufactured by the Sopwith Aviation Company during the First World War. Pilots nicknamed it the "Tripehound" or simply the "Tripe". [Bowers and McDowell 1993, p. 62.] The Triplane was built in comparatively small numbers, but the Royal Naval Air Service successfully employed it until Sopwith Camels arrived in the latter half of 1917. The Triplane continued to serve as a trainer until the end of the war.

Design and development

The Triplane began as a private venture by the Sopwith Aviation Company. The fuselage and empennage closely mirrored those of the earlier Pup, but chief engineer Herbert Smith gave the new aircraft three narrow-chord wings to provide the pilot with an improved field of view. Ailerons were fitted to all three wings. The Triplane was initially powered by the 110 hp Clerget 9Z nine-cylinder rotary engine, but most production examples were fitted with the 130 hp Clerget 9B rotary. At least one Triplane was tested with a 110 hp Le Rhône rotary engine, but this did not provide a significant improvement in performance.

The prototype Triplane, serial N500, first flew on 28 May 1916, with Sopwith test pilot Harry Hawker at the controls. The prototype proved to be easy to control and within three minutes of takeoff, Hawker startled onlookers by looping the aircraft three times in succession. [Robertson 1970, p. 59.] The Triplane was very agile, with effective, well-harmonised controls. By using the variable incidence tailplane, the aircraft could be trimmed to fly hands-off. Franks 2004, p. 19.] The introduction of a smaller eight ft span tailplane in February 1917 improved elevator response. Cooksley 1991, p. 23.]

In July 1916, N500 was sent to Dunkirk for evaluation with "A" Naval Squadron, 1 Naval Wing. It proved highly successful. The second prototype, serial N504, was fitted with a 130 hp Clerget 9B. N504 first flew in August 1916 and was eventually sent to France in December. Franks 2004, p. 50.] This aircraft served as a conversion trainer for several squadrons. Franks 2004, p. 50.]

Production

Between July 1916 and January 1917, the Admiralty issued two contracts to Sopwith for a total of 95 Triplanes, two contracts to Clayton & Shuttleworth Ltd. for a total of 46 aircraft, and one contract to Oakley & Co. Ltd. for 25 aircraft. Davis 1999, pp. 70-71.] Seeking modern aircraft for the Royal Flying Corps, the War Office also issued a contract to Clayton & Shuttleworth for 106 Triplanes. Davis 1999, p. 72.] In February 1917, the War Office agreed to exchange its Triplane orders for the Admiralty's SPAD S.VII contracts. Davis 1999, p. 72.] Mason 1992, p. 61.]

Production commenced in late 1916. Sopwith and Clayton & Shuttleworth completed their RNAS production orders, Davis 1999, pp. 70-71.] but Oakley, which had no prior experience building aircraft, delivered only three Triplanes before its contract was cancelled in October 1917. Davis 1999, p. 76.] Robertson 1970, p. 157.] For unknown reasons, the RFC Triplane contract issued to Clayton & Shuttleworth was simply cancelled rather than being transferred to the RNAS. Davis 1999, p. 72.] Total production amounted to 147 aircraft. Mason 1992, p. 61.]

Operational history

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. Franks 2004, p. 9.] No. 8 Naval Squadron received its Triplanes in February 1917. Franks 2004, p. 22.] Nos. 9 and 10 Naval Squadrons equipped with the type between April and May 1917. Franks 2004, pp. 54, 68.] The only other major operator of the Triplane was a French naval squadron based at Dunkirk, which received 17 aircraft. Franks 2004, pp. 62-63.]

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. Franks 2004, pp. 21, 69.] The Germans were so impressed by the performance of the Triplane that it spawned a brief triplane craze among German aircraft manufacturers, resulting in no fewer than 34 different prototypes. [Kennett 1991, p. 98.]

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. Franks 2004, p. 68.]

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. [Lamberton 1960, p. 74]

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. Franks 2004, p. 76.] 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. Franks 2004, p. 69.] While contemporary Albatros fighters were armed with two guns, most Triplanes were armed with a single synchronized Vickers machine gun. Efforts to fit twin guns to the Triplane met with mixed results. Clayton & Shuttleworth built six experimental Triplanes with twin guns. Mason 1992, p. 61.] 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. Franks 2004, pp. 13, 69.] Triplanes built by Oakley would have featured twin guns, an engineering change which severely delayed production. Robertson 1970, p. 157.]

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. Franks 2004, pp. 46, 49, 56-57.] No. 10 Naval Squadron converted in late August, turning over its remaining Triplanes to No. 1 Naval Squadron. Franks 2004, p. 76.] No. 1 operated Triplanes until December, suffering heavy casualties as a consequence. Franks 2004, p. 17.] By the end of 1917, surviving Triplanes were used as advanced trainers with No. 12 Naval Squadron. Davis 1999, p. 75.]

urvivors and modern reproductions

Only two authentic Sopwith Triplanes remain in existence. N5912, built by Oakley & Co. Ltd., is preserved at the RAF Museum, Hendon, Thetford 1994, p. 312.] and N5486, supplied to the Russian Government in May 1917, survives in the Central Air Force Museum, Monino, Russia. [Bruce 1990, p. 19.]

The popularity of the type has resulted in numerous modern reproductions, built by both museums and individual enthusiasts. One notable reproduction was constructed by Northern Aeroplane Workshops for the Shuttleworth Collection. It is painted to represent "Dixie II", serial N6290, of No. 8 Naval Squadron. In recognition of the reproduction's remarkable authenticity, Sir Thomas Sopwith decreed it to be a “late production” Triplane.Hiscock 1994, p. 30.]

Operators

;FRA
*French Navy (17 aircraft);flag|Russian Empire|1914
*Imperial Russian Air Force (1 aircraft);UK
*Royal Naval Air Service
**No. 1 Naval Squadron
**No. 8 Naval Squadron
**No. 9 Naval Squadron
**No. 10 Naval Squadron
**No. 11 Naval Squadron
**No. 12 Naval Squadron
** "A" Naval Squadron

pecifications (Clerget 9B-engined variant)

Aircraft specification

plane or copter?=plane
jet or prop?=prop
crew=1
length main=18 ft 10 in
length alt=5.73 m
span main=26 ft 6 in
span alt=8 m
height main=10 ft 6 in
height alt=3.2 m
area main=231 ft²
area alt=21.46 m²
empty weight main=993 lb
empty weight alt=450 kg
loaded weight main=1,415 lb
loaded weight alt=642 kg
max takeoff weight main=
max takeoff weight alt=
engine (prop)=Clerget 9B
type of prop=rotary engine
number of props=1
power main=130 hp
power alt=96 kw
max speed main=117 mph
max speed alt=187 km/h
max speed more=at 5,000 ft (1,830 m)
range main=280 mi

range alt=450 km
ceiling main=20,500 ft
ceiling alt=6,250 m
loading main=6.13 lb/ft²
loading alt=29.92 kg/m²
more performance=

Endurance: 2 hrs 45 min

Time to altitude: 6.33 min to 6,500 ft (1,980 m)
armament=

ee also

aircontent
related=
* Alcock Scout
similar aircraft=
* Sopwith Camel
* Fokker Dr.I
* Nieuport 17

see also=
* List of aircraft of the Royal Naval Air Service
lists=

References

Notes

Bibliography

* Bowers, Peter M. and Ernest R. McDowell. "Triplanes: A Pictorial History of the World's Triplanes and Multiplanes". St. Paul, Minnesota: Motorbooks International, 1993. ISBN 0-87938-614-2.
* Bruce, J.M. "Sopwith Triplane (Windsock Datafile 22)". Berkhamsted, Herts, UK: Albatros Productions, 1990. ISBN 0-94841-426-X.
* Cooksley, Peter. "Sopwith Fighters in Action (Aircraft No. 110)". Carrollton, Texas: Squadron/Signal Publications, 1991. ISBN 0-89747-256-X.
*Davis, Mick. "Sopwith Aircraft". Ramsbury, Marlborough, Wiltshire: Crowood Press, 1999. ISBN 1-86126-217-5.
* Franks, Norman. "Sopwith Triplane Aces of World War I (Aircraft of the Aces No. 62)". Oxford: Osprey Publishing, 2004. ISBN 1-84176-728-X.
* Hiscock, Melvyn. "Classic Aircraft of World War I (Osprey Classic Aircraft)." Oxford: Osprey Publishing, 1994. ISBN 1-85532-407-5.
* Kennett, Lee. "The First Air War: 1914-1918". New York: The Free Press, 1991. ISBN 0-02917-301-9.
* Lamberton, W.M., and E.F. Cheesman. "Fighter Aircraft of the 1914-1918 War". Letchworth: Harleyford, 1960. ISBN 0-90043-501-1.
* Mason, Francis K. "The British Fighter Since 1912". Annapolis, Maryland: Naval Institute Press, 1992. ISBN 1-55750-082-7.
* Robertson, Bruce. "Sopwith – The Man and His Aircraft". London: Harleyford, 1970. ISBN 0-90043-515-1.
* Thetford, Owen. "British Naval Aircraft Since 1912". London: Putnam, 1994. ISBN 0-85177-861-5

External links

* [http://www.aviation-history.com/sopwith/triplane.html The Sopwith Triplane- Great Britain]
* [http://www.aviation.technomuses.ca/collections/artifacts/aircraft/SopwithTriplane.shtml Canada Aviation Museum: Sopwith Triplane]