The Boulton & Paul P.3 Bobolink was the company's first internally designed aircraft, and was produced in response to a competition to replace the Sopwith Camel.
Before the First World War Boulton & Paul had constructed wooden buildings, but during the war it became an aircraft manufacturer, building other company's designs under licence (including the Sopwith Camel). As often happened this led to a desire to design their own aircraft, and when a design contest was called to produce a replacement for the Camel, Boulton & Paul decided to enter. Specification A.1A called for an aircraft powered by the 230hp Bentley B.R.2 rotary engine.
They put forward two designs, the Bentley powered P.3 and the P.5, an obscure design of which three were ordered but none built. Both of these aircraft were produced by John North, Boulton & Paul's chief designer for many years. The orders were placed at the same time, on 1 December 1918, and the P.5 got the serial numbers C8652 to C8654 while the P.3 was given C8655 to C8657.
The P.3 Bobolink was a two bay biplane (unlike the single bay Camel, but similar to the two bay Sopwith Snipe). It was powered by the Bentley rotary engine as the Snipe, and was generally similar in layout to the Sopwith machine. The Bobolink used 'N' interplane struts, which eliminated the need for incidence bracing between the front and rear struts. It had equal span staggered wings, with a 2ft 3.5in stagger. The upper wing was bigger than the lower wing. Both wings had a small amount of dihedral.
Its most unusual feature was that the main fuel tanks could be jettisoned if the aircraft caught fire. It also had two separate fuel tanks, one carrying 34 gallons and one carrying 6 gallons, with an armour plate between the two to reduce the fire risk. The P.3 had a standard wooden structure with a fabric covering. The original design only had ailerons on the lower wings, but they were added to the upper wings before the official trials. The tail had a swept back leading edge and a curved top and back, while the horizontal tail surfaces were rectangular. It was armed with two forward firing Vickers machine guns and could carry a Lewis gun ont eh upper wing.
The P.5 and possibly the P.3 were originally named the Hawk, but bird of prey names were for aircraft engines. The name was changed to Boblink and then to Bobolink, an American song bird.
Three serial numbers were allocated to the Bobolink, but it is likely that only a single prototype was built. This aircraft, C8655, got the fourth B.R.2 engine, made its maiden flight early in 1918 and was then sent to Martlesham Heath in March 1918. The other two prototypes were officially cancelled on 9 April 1918.
The trials showed that the Austin Osprey was the most manoeuvrable, with the Bobolink coming out worst in that area. However the Osprey was a triplane, and was the slowest of the four aircraft being tested. The Nieuport BN.1 was the fastest of the four, but caught fire in the air on 10 March 1918 and was destroyed.
The contest was won by the Sopwith Snipe, which had similar performance figures to the Bobolink, but was considered to be easier to mass produce. Sopwith also had a reputation for producing excellent aircraft. The Bobolink was rated fourth out of the four designs. Boulton & Paul were rewarded with a contract to produce 400 Snipes, later increasing to 500, of which 415 to 425 were completed (although none were completed in time to see combat).
Engine: Bentley B.R.2 Rotary Engine
Span: 29ft 0in
Length: 20ft 0in
Height: 8ft 4in
Empty weight: 1,226lb
Maximum take-off weight: 1,992lb
Max speed: 125mph at 10,000ft, 109mph at 15,000ft
Climb Rate: 5min 20sec to 6,500ft
Service ceiling: 19,500ft
Endurance: 3 hours 15 minutes
Armament: Two fixed forward firing 0.303in Vickers gun on upper fuselage, space for 0.303in Lewis gun above wing centre section