The Bristol Scout was a single-seat biplane with a rotary engine. It was first made to race, but later used by the RNAS and RFC as a scout, which means a fast aircraft for spying on enemy movements. It was among the first single-seat planes used as a fighter, but it could not carry weapons that fired forward until British-designed gun synchronizers were created in 1916. By then, the Scout was outdated. In British military use, single-seat fighters were still called "scouts" until the early 1920s.

Design and development

The Bristol Scout was designed in the second half of 1913 by Frank Barnwell and Harry Busteed, Bristol's chief test pilot. While testing the Bristol X.3 seaplane, Busteed and Barnwell thought of building a small, high-performance biplane. This idea came from a separate secret design department led by Barnwell. The design was first given the works number SN.183, which was taken from a canceled project for the Italian government. This project was led by Henri Coanda, and some parts of it, like the fuselage and drawings, remained in the workshop with this number.

The aircraft was an equal-span single-bay biplane with staggered parallel-chord wings. The wings had raked wingtips and ailerons on both the upper and lower wings. The wings were rigged with about half a degree of dihedral, making them appear almost straight when viewed from the front. The wing section was designed by Coanda and used in the Bristol Coanda Biplanes. The fuselage was a rectangular wooden structure made from ash and spruce, with aluminum sheeting on the front and fabric covering on the rear. It was powered by an 80 hp (60 kW) Gnome Lambda rotary engine enclosed in a cowling with no open frontal area. The bottom of the cowling was cut away to allow cooling air to reach the engine. The aircraft had a rectangular balanced rudder with no fixed fin and split elevators attached to a non-lifting horizontal stabilizer. The tail surfaces were made of steel tubes and wooden ribs, and the elevators were entirely made of steel tubes.

The first flight of the Bristol Scout took place on 23 February 1914 at Larkhill, piloted by Busteed. It was later shown at the March 1914 Aero Show in London. After more testing at Larkhill, the prototype, later called the Scout A, was returned to the factory at Filton. It was modified with larger wings, increasing the chord by six inches (15 cm) and the span from 22 ft (6.71 m) to 24 ft 7 in (7.49 m). The wings were rigged with a greater dihedral of 1 + 3⁄4°. Other changes included a larger rudder, a new open-fronted cowling with six external stiffening ribs, and fabric-covered wheels. The aircraft was tested by the British military on 14 May 1914 at Farnborough. Piloted by Busteed, it reached an airspeed of 97.5 mph (157 km/h) and had a stalling speed of 40 mph (64 km/h). It was entered in the 1914 Aerial Derby but did not compete due to poor weather.

At this time, two more aircraft (works numbers 229 and 230) were being built. The prototype was sold to Lord Carbery for £400 without its engine. Carbery added an 80 hp Le Rhône 9C rotary engine and entered it in the London–Manchester race on 20 June. However, the aircraft was damaged during landing at Castle Bromwich and had to withdraw. After repairs, including widening the undercarriage track, Carbery entered the aircraft in the London–Paris–London race on 11 July. During the return leg, the aircraft was lost in the English Channel after only one fuel tank was filled by mistake. Carbery escaped by landing near a ship, but the aircraft was destroyed.

Numbers 229 and 230, later called the Scout B, were identical to the modified Scout A but had half-hoop-style underwing skids. They also had six stiffening ribs around the engine cowling and a larger rudder. These aircraft were completed in August 1914, shortly after the outbreak of war, and were taken by the War Office. They received Royal Flying Corps serial numbers 644 and 648, with one assigned to No. 3 Squadron and the other to No. 5 Squadron for testing. Number 644 was damaged beyond repair on 12 November 1914 during a crash landing.

Impressed by the aircraft’s performance, the War Office ordered twelve examples on 5 November 1914, and the Admiralty ordered 24 more on 7 November. The production aircraft, later called the Scout C, differed mainly in construction details. The cowling had a small frontal opening and no stiffening ribs. The top decking in front of the cockpit had a deeper curve, and the aluminum covering on the fuselage sides extended only to the forward center-section struts. Behind these struts, the decking was made of plywood.

Operational history

The Bristol Scout served from 1914 to 1916 and was the first aircraft clearly designed as a fighter. Early efforts to add forward-firing guns to British aircraft were tested using Bristol Scouts. This began with the second Scout B, RFC number 648, which had two rifles mounted on each side, aimed outward and forward to avoid hitting the propeller.

Two early Bristol Scout C aircraft, numbers 1609 and 1611, were used by Captain Lanoe Hawker of No. 6 Squadron RFC. After 1609 was damaged in combat, 1611 was equipped with a Lewis machine gun on the left side of the fuselage, similar to the rifle setup on the second Scout B. Hawker designed the gun mount. On 25 July 1915, Hawker shot down two German planes and forced a third to retreat near Passchendaele and Zillebeke. For this, he was awarded the first Victoria Cross ever given to a British pilot for aerial combat against enemy aircraft. This followed earlier Victoria Cross awards to William Rhodes-Moorhouse and Reginald Warneford in 1915.

Some of the first 24 Bristol Scout Cs built for the Royal Naval Air Service (RNAS) had one or two Lewis machine guns. Some pilots placed the gun on the upper wing, like the Nieuport 11, while others mounted it on the front of the fuselage, which risked damaging the propeller. A method using bullet-deflecting wedges, similar to what Roland Garros tested on his plane, was tried on an RFC Scout C, number 5303. However, this method required a large spinner that blocked engine cooling, so it was not used again.

An RNAS Scout became the first landplane to fly from a ship when Flight Lieutenant H. F. Towler flew No. 1255 from the deck of HMS Vindex on 3 November 1915. Some RNAS Scout Ds were armed with Ranken Darts, which were explosive flechettes stored under the pilot’s seat. On 2 August 1916, Flight Lieutenant C. T. Freeman attacked Zeppelin L 17 with Ranken Darts from Vindex. The attack caused no damage, and Freeman had to ditch his plane because he could not return to the ship or land safely.

In March 1916, RFC Scout C number 5313 was equipped with a Vickers machine gun using the Vickers-Challenger synchronizing gear, the only option available at the time. Six other Scouts also had this setup. The gear worked only when the gun was on the left side of the fuselage. Attempts to use it for a centrally mounted gun failed, and no Vickers-armed Bristol Scouts were used in combat after tests ended by May 1916.

No squadron used only Bristol Scouts, and by late 1916, no new Scouts were supplied to British forces. Early fighter squadrons in the Royal Flying Corps instead used the Airco DH.2 Pusher configuration. Some Scouts were sent to the Middle East, Macedonia, and the Eastern Mediterranean. The last known Bristol Scout in service was RNAS Scout D number 8978 in Australia, which operated at Point Cook near Melbourne until October 1926.

After leaving frontline duty, Bristol Scouts were used for training. Many were kept by senior officers for personal use. No. 5570 survived the war and was later owned privately before being scrapped in 1933.

Variants

The first model of the aircraft was a single prototype.

Two aircraft were built that were the same as the modified Scout A, except they had underwing skids shaped like half hoops and a larger rudder.

These early Scout C models were similar to the Scout B. A total of 36 Scout C aircraft were made—12 for the Royal Flying Corps and 24 for the Royal Naval Air Service. These aircraft had their main oil tank moved behind the pilot’s shoulders, which required a raised section on the back of the pilot’s seat to fit. They also used a small, dome-shaped front cover for the engine, which was only meant to work with the 80 horsepower Gnome Lambda rotary engine, a type of engine preferred by the Royal Naval Air Service.

After the first 36 Scout C aircraft were built, later batches included 50 for the RNAS and 75 for the RFC. These models used a flat-fronted, shorter cover that could fit either the Gnome Lambda rotary engine or the 80 horsepower Le Rhône 9C rotary engine. The oil tank was moved forward, in front of the pilot, to improve balance and engine performance. The flat-fronted cover still had a small opening like the dome-shaped one, and both designs had a curved slot near the bottom of the cover to help cool the engine and drain fuel or oil. A total of about 161 Scout C aircraft were made for the British military. Over time, these models gradually changed to become the Scout D.

The final and most common version, the Scout D, was created by making several improvements to the Scout C. Early changes included increasing the wing angle from 1 + 3⁄4° to 3° on 17 of the 75 naval Scout C aircraft. Other models in the same production run had larger horizontal tail wings, a broader rudder, shorter ailerons, and a larger front opening on the cover, similar to the Scout B but without extra stiffening ribs.

Some newer covers had a bulge on the lower right side to help remove exhaust gases more efficiently. This was designed to fit the more powerful 100 horsepower Gnome Monosoupape B2 rotary engine in later models, improving the Scout D’s performance. A total of 210 Scout D aircraft were made, with 80 ordered by the RNAS and 130 by the Royal Flying Corps.

• S.2A: A two-seat version of the Scout D used as a fighter aircraft. Two were built for advanced training.

Operators

• Royal Flying Corps
• Royal Naval Air Service
• Australian Flying Corps: No. 1 Squadron AFC in Egypt and Palestine; No. 6 (Training) Squadron AFC in the United Kingdom; Central Flying School AFC in Point Cook, Victoria.
• Hellenic Navy
• The Ottoman Air Force used some captured Bristol scouts.

Surviving aircraft and reproductions

Two important copies and one replica of the Bristol Scout have been built for flying. In 1962, Leo Opdycke, who started a World War I magazine called AERO, began building a copy of the Scout D in New York State. This copy was designed to use a Le Rhône 9C 80 horsepower rotary engine. The plane was built slowly at his home in Poughkeepsie, New York, from the 1960s until the 1980s. After it was completed, it was moved to the Old Rhinebeck Aerodrome nearby and flown once there successfully, but had a small accident that did not hurt anyone. Today, the complete airframe, including the engine, is on display at the Fleet Air Arm Museum in Yeovilton, UK.

Another copy is a reproduction of the Bristol Scout C, which was originally numbered No. 1264. This was one of the first 24 Scout Cs built for the Royal Naval Air Service (RNAS). The copy uses parts from the original plane, including the joystick, rudder bar, and still-working Bosch starting magneto. David and Richard Bremner, who are the grandchildren of the original pilot of No. 1264, wanted to build a working copy of their grandfather’s plane in 2002. They used parts from their grandfather’s original aircraft. Research began in 2002, and the plane’s frame was built starting in 2008. The copy, powered by a Le Rhône 9C rotary engine like Opdycke’s earlier project, flew for the first time on July 9, 2015. It was flown near Gallipoli, where their grandfather’s original Scout C was based from December 1915 to August 1916.

A Bristol Scout D replica flies with the NZ Warbirds Association at Ardmore Airport in Auckland, New Zealand. This copy was built in California by Herb Harkey in the 1990s and finished in 1997. It includes original parts from the time, such as cockpit instruments and an authentic 80 horsepower Le Rhône engine. The plane arrived in New Zealand in 2018 and is often displayed at the NZ Warbirds Association’s annual airshows and open days.

Another full-size copy of the Bristol Scout D, numbered No. A1742, is on display at the Aerospace Bristol museum, located at the former Filton Aerodrome.

Specifications (Bristol Scout D)

Data from Bristol Aircraft since 1910

General characteristics

• Crew: 1
• Length: 20 ft 8 in (6.30 m)
• Wingspan: 24 ft 7 in (7.49 m)
• Height: 8 ft 6 in (2.59 m)
• Wing area: 198 sq ft (18.4 m²)
• Empty weight: 789 lb (358 kg)
• Gross weight: 1,195 lb (542 kg)
• Powerplant: 1 × Le Rhône 9C 9-cylinder air-cooled rotary engine, 80 hp (60 kW)
• Propellers: 2-bladed fixed-pitch propeller

• Maximum speed: 94 mph (151 km/h, 82 kn)
• Range: 187 mi (301 km, 162 nmi)
• Endurance: 2 hours 30 minutes
• Service ceiling: 16,000 ft (4,900 m)
• Time to reach 10,000 ft (3,048 m): 18 minutes 30 seconds
• Wing loading: 6.03 lb/sq ft (29.4 kg/m²)
• Power-to-weight ratio: 0.067 hp/lb (0.110 kW/kg)

• Guns: 1 × Lewis or Vickers machine gun