The Sopwith 'Pup' was a single-seat, biplane fighter which was introduced to the RFC and RNAS in the mid-stages of the Great War.
Originally named the Sopwith 'Scout', it was soon nicknamed by pilots and mechanics because it was seen as the 'pup' to the larger Sopwith Strutter, which entered service at around the same time.
Impact
The fighter was very well received when it entered service in 1916 because RFC pilots had been struggling to fight against superior German machines, with many squadrons being forced to go up against fast, single-seat fighters such as the new Albatross DIII, in old, out-of-date two-seater fighters/bombers.
The Pup, although under-powered in comparison to most of its rivals, had vastly superior manoeuvrability and possessed much better turning power and control.
The famed German ace Manfred Von Richthofen was quoted as saying "We saw at once that the enemy aeroplane was superior to ours."
It was also of valuable use to the RNAS thanks to its ability to take off and land on very small areas, making it ideal for their attempts at developing ship-based launching of aircraft.
Armament
The Pup was, to many pilots, their first experience with a synchronised, forward-firing machine gun. While the technology for this had already been developed, most British pilots, until this point, had been using weapons mounted elsewhere on the machine, or relying on secondary weapons or gunners in two-seater fighters.
The synchronised, Vickers machine gun was capable of firing through the propeller and allowed pilots to fire with much greater accuracy, and with far less movement required on their part. It was, however, not perfect, and there were a number of occasions where the mechanism would either jam, or simply (and quite comically) destroy their own propeller
Lifespan
The effective lifespan of the Pup was to be short-lived. This was mainly due to the incredibly accelerated rates of aircraft development throughout the Great War.
By late 1917, the latest German fighters were already beginning to outclass the Pup in many areas. Fighters such as the Fokker Triplane were beginning to dominate the skies.
Sopwith were frantically developing aircraft themselves and soon were ready to start producing their own Triplane, as well as what would go on to become the most popular British aircraft of the war, the Sopwith Camel. Eventually, towards the end of 1917 and the beginning of 1918, the now exasperated Pups were taken out of service on the front line to be replaced by the superior Camel, to the great relief of many fighter squadrons on the front, who took more losses in 1917 than in any other year of the war.
The Pup did, however, stay in use until the end of the war, mainly in home defence duties, defending against the Zeppelin and Gotha bomber attacks on London.
Fondly remembered, quickly forgotten
Under normal circumstances*, the Pup might have been remembered as a legendary plane, and was often spoken of fondly by pilots during and after the war. If it hadn't been for the rate of aircraft development at the time, the plane might have left a much bigger mark on aviation history. In the end though, it was its younger brother, the Sopwith Camel which stole the show and gave the tired RFC fighter squadrons a fighting chance in the bitter final stages of the war.
* Although, under 'normal' circumstances, it could be argued that none of these machines would have been developed until much, much later, if at all. Aviation as a whole was very much in its infancy when the war broke out. Once the importance of air superiority became clear to military commanders, its development became highly competitive