Sopwith’s Last Fighter
The famed blood-red triplane design of the Red Baron Manfred Von Richthofen’s Fokker Dr.I became the iconic image of the air war over the Western Front of World War I. Richthofen’s Dr.I became an indispensable tool for the German propaganda machine and in an age of countless biplane designs there was a feeling in the general public that this “extra wing” was what made Richthofen so unbeatable in the air.
In reality the triplane design was something of fad in aviation design that was quickly falling out of favour. Triplanes had the advantage of being able to use shorter span wings with the same or even greater levels of agility than an equivalent biplane which made them smaller targets in the air than an equivalent De Havilland DH.4. The trade-off however was that triplanes were often heavier than their biplane counterparts and incurred far more drag. They were also prone to cross wind interference which was especially dangerous on landing. As the air war dragged on over the trenches it became increasingly obvious that speed was going to be the deciding factor and the newer biplanes were able to surpass even the feared the Dr.I in this respect.
Nevertheless some aircraft designers persevered with the configuration believing they could find a balance between the agility a triplane offered and the speed of the latest biplanes. One such company was Sopwith of Great Britain who had produced the near legendary Sopwith Camel, Snipe and Pup fighters. Sopwith had long been a proponent of triplane designs and in early 1917 their appropriately named Sopwith Triplane fighter entered very limited service with the Royal Naval Air Service.
Spurred on by this brief success Sopwith decided to return to the triplane configuration when in early 1918 the Air Ministry requested proposals for a replacement for the Snipe. Sopwith knew that the triplane was falling out of favour and took no chances designing a common fuselage and tail section that could be fitted with either a biplane or triplane configuration. This produced two aircraft the Snapper (biplane) and the Snark (triplane). As designed the Snark had a wooden monocoque fuselage with equal span single-bay wings each fitted with ailerons for a high degree of agility. The wings were unequally spaced and staggered with the gap between the mid and upper wings being less than that between the lower and mid wings.
Included in the specification was the requirement for the aircraft to be powered by the ABC Motors Ltd Dragonfly I 320hp engine then under development. The Dragonfly was an air cooled radial engine which promised very high performance and based on this promise the Air Ministry decided it was to become the main engine for the next series of combat aircraft for the newly formed Royal Air Force. For the aircraft manufacturers this would prove to be a frustrating and costly decision for the aeroengine proved extremely problematic and ABC constantly had to push back its service entry. This delayed numerous aircraft projects such as the promising Avro 533 Manchester bomber and Sopwith’s Snark.
Despite the problems with the engine the Air Ministry was sufficiently interested in Sopwith’s Snark to order three prototypes for testing on May 14th 1918. One of the aircraft’s main selling points was that for its day it had an exceptionally heavy armament. Nearly all British aircraft of the period had the proven configuration of two .303 (7.7mm) Lewis machine guns mounted forward of the pilot synchronized with the propeller and indeed the Snark did feature two such weapons. Additionally however the aircraft featured four more Lewis guns under the lower wing firing outside of the propeller arc; a configuration more akin to World War Two fighters. Despite the fact that the pilot couldn’t reach these weapons in-flight to reload them or correct a jam it did mean that the Snark had huge potential as a bomber destroyer although the weapons did add even more weight to the aircraft.
Sopwith’s engineers worked steadily to produce the three prototype airframes by October 1918 but the Dragonfly I engine was nowhere to be seen and so the three prototypes sat grounded until finally the first Dragonfly I aeroengine was delivered in early 1919 well after the armistice ended the war it was designed to fight in. The aircraft finally took flight sometime in July 1919 (exact date is unknown) and the first flying prototype arrived at Martlesham Heath for official trials on the 12th of November 1919. The other two prototypes still had to wait for their engines to be delivered and the second prototype didn’t reach Martlesham until March 17th 1920 while the third prototype, which was fitted with a 360hp Dragonfly la engine, didn’t arrive until much later in the year.
Testing must have been a sullen experience for those involved from Sopwith. The company was in trouble and a lot was riding on the Snark’s success. Testing of the first two prototypes revealed that it had fine handling qualities being quite responsive although not as nimble as previous triplanes. It achieved a top speed of 130mph, 9mph faster than the Snipe it was to replace, but this came at a price. The loathsome Dragonfly engine was not yet finished ruining the Snark’s prospects and proved horribly unreliable being prone to overheating in flight. Testing continued at a relaxed pace in to 1921 but by then the requirement for a Snipe replacement was brought in to question as the RAF found itself watching every single penny almost lecherously. The detection of deterioration in the fuselage structure sounded the death knell for the Snark and all three were written off by the end of the year.
It was a sad end to the great Sopwith Company who had been at the forefront of British fighter technology throughout the war. Even before the Snark project ended the company had gone in to liquidation it being unable to survive in the harsh post war climate where its expertise in fighter design was no longer wanted.
- ENGINE: 1 x 320hp ABC Dragonfly radial engine
- MAX SPEED: 130 mph
- WINGSPAN: 8.08m (27ft 6in)
- LENGTH: 6.25m (21ft 6in)
- HEIGHT: 3.30m (11ft 10in)
- WING AREA: 29.91 m2 (321.95 sq ft)
- ARMAMENT: 6x .303 (7.7mm) Lewis Mchine guns