Sopwith Camel

The Sopwith Camel is a British First World War single-seat biplane fighter aircraft that was introduced on the Western Front in 1917. It was developed by the Sopwith Aviation Company as a successor to the Sopwith Pup and became one of the best known fighter aircraft of the Great War.

The Camel was powered by a single rotary engine and was armed with twin synchronized Vickers machine guns. Though difficult to handle, it was highly manoeuvrable in the hands of an experienced pilot, a vital attribute in the relatively low-speed, low-altitude dogfights of the era. In total, Camel pilots have been credited with downing 1,294 enemy aircraft, more than any other Allied fighter of the conflict. Towards the end of the First World War, the type also saw use as a ground-attack aircraft, partly because the capabilities of fighter aircraft on both sides had advanced rapidly and left the Camel somewhat outclassed.

The main variant of the Camel was designated as the F.1. Other variants included the 2F.1 Ship's Camel, which operated from aircraft carriers; the Comic night fighter variant; and the T.F.1, a "trench fighter" armoured for attacks on heavily defended ground targets. A two-seat variant served as a trainer. The last Camels were withdrawn from RAF service in January 1920.

Development

When it became clear the Sopwith Pup was no match for the newer German fighters such as the Albatros D.III, the Camel was developed to replace it,Bruce ''Flight'' 22 April 1955, p. 527. as well as the Nieuport 17s that had been purchased from the French as an interim measure. It was recognised that the new fighter needed to be faster and have a heavier armament. The design effort to produce this successor, initially designated as the ''Sopwith F.1'', was headed by Sopwith's chief designer, Herbert Smith.Bruce 1965, p. 3.

Early in its development, the Camel was simply referred to as the "Big Pup". A metal fairing over the gun breeches, intended to protect the guns from freezing at altitude, created a "hump" that led pilots to call the aircraft "Camel", although this name was never used officially. On 22 December 1916, the prototype Camel was first flown by Harry Hawker at Brooklands, Weybridge, Surrey; it was powered by a Clerget 9Z.Jackson 2007, p. 2.

In May 1917, the first production contract for an initial batch of 250 Camels was issued by the British War Office.Bruce 1965, p. 5. Throughout 1917, a total of 1,325 Camels were produced, almost entirely the initial F.1 variant. By the time that production of the type came to an end, approximately 5,490 Camels of all types had been built.Bruce ''Flight'' 29 April 1955, p. 563. In early 1918, production of the naval variant of the Sopwith Camel, the "Ship's" Camel 2F.1 began.Bruce 1965, p. 6.

Design

Overview

The Camel had a mostly conventional design for its era, featuring a wooden box-like fuselage structure, an aluminium engine cowling, plywood panels around the cockpit, and a fabric-covered fuselage, wings and tail. While possessing some clear similarities with the Pup, it was furnished with a noticeably bulkier fuselage. For the first time on an operational British-designed fighter, two 0.303 in (7.7 mm) Vickers machine guns were mounted directly in front of the cockpit, synchronised to fire forwards through the propeller disc – initially this consisted of the fitment of the Sopwith firm's own synchronizer design, but after the mechanical-linkage Sopwith-Kauper units began to wear out, the more accurate and easier-to-maintain, hydraulic-link Constantinesco-Colley system replaced it from November 1917 onward. In addition to the machine guns, a total of four Cooper bombs could be carried for ground attack purposes.

The bottom wing was rigged with 5° dihedral while the top wing lacked any dihedral; this meant that the gap between the wings was less at the tips than at the roots; this change had been made at the suggestion of Fred Sigrist, the Sopwith works manager, as a measure to simplify the aircraft's construction. The upper wing featured a central cutout section for the purpose of providing improved upwards visibility for the pilot.

Production Camels were powered by various rotary engines, most commonly either the Clerget 9B or the Bentley BR1. In order to evade a potential manufacturing bottleneck being imposed upon the overall aircraft in the event of an engine shortage, several other engines were adopted to power the type as well.

Flight characteristics

Unlike the preceding Pup and Triplane, the Camel was considered to be difficult to fly. With light and sensitive controls the type owed both its extreme manoeuvrability and its difficult handling to the close placement of the engine, pilot, guns and fuel tank (some 90% of the aircraft's weight) within the front of the aircraft, and to the strong gyroscopic effect of the rotating mass of the cylinders common to rotary engines.As compared with radial engines in which a conventional rotating crankshaft is driven by a fixed engine block.

Due to the torque of the rotary engine the Camel turned more slowly to the left, which resulted in a nose-up attitude, but the torque also resulted in being able to turn to the right quicker than other fighters,Clark 1973, p. 134. although that resulted in a tendency towards a nose-down attitude from the turn. Because of the faster turning capability to the right, some pilots preferred to change heading 90° to the left by turning 270° to the right.

Upon entering service, the Camel gained an unfortunate reputation with pilots,Jackson 2005, pp. 15–16. with inexperienced ones crashing on take-off when the full fuel load pushed the aircraft's centre of gravity beyond the rearmost safe limit.

When in level flight, the Camel was markedly tail-heavy. Unlike the Sopwith Triplane, the Camel lacked a variable incidence tailplane, so that the pilot had to apply constant forward pressure on the control stick to maintain a level attitude at low altitude. The aircraft could be rigged so that at higher altitudes it could be flown "hands off". A stall immediately resulted in a dangerous spin.
RFC pilots used to joke that it offered the choice between "a wooden cross, the Red Cross, or a Victoria Cross".

A two-seat trainer version was later built to ease the transition process: in his ''Recollections of an Airman'', Lieutenant Colonel L. A. Strange, who served with the central flying school, wrote: "In spite of the care we took, Camels continually spun down out of control when by pupils on their first solos. At length, with the assistance of Lieut Morgan, who managed our workshops, I took the main tank out of several Camels and replaced hemwith a smaller one, which enabled us to fit in dual control." Such conversions, and dual instruction, went some way to alleviating the previously unacceptable casualties incurred during the critical type-specific solo training stage.

Despite these issues, its agility in combat made the Camel one of the best-remembered Allied aircraft of the First World War. Aviation author Robert Jackson notes that: "in the hands of a novice it displayed vicious characteristics that could make it a killer; but under the firm touch of a skilled pilot, who knew how to turn its vices to his own advantage, it was one of the most superb fighting machines ever built".

Operational history

Western front

In June 1917, the Sopwith Camel entered service with No. 4 Squadron of the Royal Naval Air Service, which was stationed near Dunkirk