Bristol Scout
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For the later monoplane, see Bristol M.1 Monoplane Scout
The Bristol Scout was a simple, single seat, rotary-radial engined biplane that functioned as one of the very first UK-built and designed fighter aircraft for the British armed forces in the first two years of World War I, even though it was originially intended to be a sporting aircraft for the rich when it was first conceived.
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[edit] Development
Designed in the second half of 1913 by Frank Barnwell and Harry Busteed, the first prototype of the Bristol Scout series was first flown on 23 February 1914 by co-designer Busteed, and was first seen in public at the March 1914 London Olympia exhibition centre's Aero Show event. It could have been said to have been somewhat "comical" in general appearance at that time in its original form, with characteristics such as a main landing gear wheel track measured at only 39 inches (99 cm) that was barely wider than the fuselage, only about a one half degree dihedral angle on the wing panels, making them look almost totally "flat" across from a nose-on view, and an engine cowl that had no open frontal area, even though the extreme bottom was sliced away horizontally to allow cooling air to get to its seven cylinder 80 hp Gnôme Lambda rotary engine, as well as a squared-planform "all-flying" rudder with no fixed vertical fin, which would become a hallmark (even though the shape was different) of Fokker-designed German fighter aircraft in World War I up through the Fokker D.VI.
[edit] Variants
[edit] Scout A
After its first public appearance, by May 1914 what would later become known as the "Bristol Scout A" had been refitted with a longer span - at 24 ft 7 in (7.49 m) compared to the initial 22 ft (6.71 m) - set of wing panels that were rigged with 1-3/4º of dihedral, a larger surface area rudder, and a much more conventional open-front, ring-style, "six segment" cowl to house the 80 hp Gnôme Lambda rotary engine. The British military first evaluated the Scout A aircraft on May 14 1914, at Farnborough when the aircraft showed then fast airspeed of 97.5 mph (157 km/h).
The Scout A also entered two air races in the summer of 1914 after being purchased by British Lord Carbery for £400 without its engine. Flying with an 80 hp Le Rhone 9C nine cylinder rotary installed by its purchaser it was ditched in the English Channel during the second air race it participated in; a round trip from Hendon in the UK to the French Buc aerodrome [near Versailles] and back, due to its running out of fuel. While in France, the tanks had been only half filled by mistake.
[edit] Scout B
Two Scout B aircraft, identical to the modified Scout A aircraft with the 80 hp Le Rhone rotary for power, except for having half-hoop-style underwing skids mounted on them, and a widened rudder surface, were built for military evaluation just as the Austro-Hungarian Archduke Franz Ferdinand was shot in Sarajevo Bosnia. The outbreak of the First World War followed shortly. These two Scout B aircraft, bearing Royal Flying Corps serial numbers 644 and 648, first saw evaluational service from September 20 1914, with the first one, bearing RFC serial number 644, being damaged beyond repair on November 12 of that year on a crash landing.
[edit] Scout C
The Scout C aircraft, very similar to the previous Scout B, was first ordered by the British government on November 5 1914, in a 12 aircraft production batch for the Royal Flying Corps, and on December 7 1914 by the competing Royal Naval Air Service (RNAS) in a 24-aircraft batch. Both these first two production batches of the Scout C aircraft were powered by the 80 hp Gnôme Lambda rotary, just as the Scout A had been, and when compared to the Scout B before it, these first 36 Scout C aircraft were fitted out with unusual "dome-front" cowls with much smaller frontal openings than the Scout B's six segment cowl had possessed. These early Scout C aircraft also had their main oil tank moved to a position directly behind the pilot's shoulders, requiring a raised rear dorsal fairing immediately behind the pilot's seat, to accommodate the oil tank and its filler cap.
Later Scout C production batches, comprising 50 aircraft built for the RNAS and 75 for the RFC, changed the cowl to a flat-fronted, and longer-depth version more able to house the alternate choice of an 80 hp Le Rhone 9C rotary engine when the Gnôme Lambda was not used, and moved the oil tank forward to a position in front of the pilot, for better weight distribution and more reliable engine operation. The later cowl for the remaining Scout C aircraft still had the small opening of the domed unit, but often had a small cutaway made to the lower rear edge of the cowl to increase the cooling effect.
[edit] Scout D
The last, and most numerous production version, the Scout D, gradually came about as a series of further improvements to the Scout C design. One of the earliest changes that marked the change to the Scout D version showed up on seventeen of the 75 naval Scout Cs with an increase in the wing dihedral angle from 1-3/4º to 3º, and other aircraft in the 75-plane naval Scouts production run introduced larger tail surfaces, shorter-span ailerons, and a large front opening for the cowl, much like the Scout B had used, but made as a "one-piece" ring cowl, sometimes with a blister on the starboard lower side, when it was meant to house the eventual choice of the more powerful nine cylinder 100 hp Gnôme Monosoupape rotary engine in later production batches, to improve its peformance. Some 210 examples of the Scout D version were produced, with 80 of these being ordered by the RNAS, and the other 130 being ordered by the Royal Flying Corps.
[edit] Operational history
The era within which the Bristol Scout aircraft series existed, from 1914 to 1916, was basically "the dawn of military aviation" in World War I, and many of the earliest attempts to arm British military aircraft with weaponry were attempted with the Bristol Scout series.
The first known attempt to arm a Bristol Scout aircraft occurred with the second Scout B, RFC number 648, which was experimentally fitted with two rifles, one per side, as its armament, aimed outwards and forwards to clear the propeller arc.
Two of the Royal Flying Corps' early Bristol Scout C aircraft, numbers 1609 and 1611, flown by Captain Lanoe Hawker with the RFC's No. 6 Squadron, had each in their turn been armed with a single Lewis machine gun on the left side of the fuselage, within a mount that Capt. Hawker had designed himself, almost identically in the manner of the rifles tried on the second Scout B. When Lanoe's No.1611 aircraft was used by him to down two German aircraft and force off a third on July 25 1915 over Passchendaele and Zillebeke he was awarded the first Victoria Cross ever given for a British military pilot's actions in aerial combat.
A number of the RNAS Scout C aircraft were armed with single Lewis machine guns, sometimes with the Lewis gun mounted atop the upper wing center section in the manner of the Nieuport 11, and even more common was an apparently very dubious choice of placement by some RNAS pilots, in mounting the Lewis gun on the forward fuselage of their Scout Cs, just as if it was a synchronized weapon (which it was not) firing directly forward and through the propeller arc; an action likely to result in serious propeller damage. The type of bullet-deflecting wedges as Roland Garros had tried on his Morane-Saulnier Type N monoplane were also tried on one of the RFC's last Scout Cs, No. 5303, but since this seemed, in this instance, to have also required the use of the Morane Type N's immense "casserole" spinner, which almost totally blocked cooling air from reaching this particular Scout C's 80-hp Le Rhône rotary engine, the deflecting-wedge concept for propeller protection from bullets was not pursued further with Bristol Scouts.
In the early WW I attempts to down German Zeppelin airships, one unusual weapon tried from a RNAS Scout D was the "Ranken Dart", a type of droppable, explosive-laden flechette with 1 lb (0.45 kg) of explosive per projectile. Scout D No. 8953, flown by Flt. Lt. C. T. Freeman, flew from the deck of the flight-deck-converted Isle of Man packet steamer HMS Vindex (formerly with the civilian name Viking), which possessed a take-off deck on its forward half, and on August 2 1916, Flt Lt. Freeman tried to down the Zeppelin L.17 with Ranken Darts, released from two vertically-oriented internal cylindrical containers located just behind his feet, in the belly of his Scout D. None of the darts did any damage to the Zeppelin, and since Freeman's aircraft could not land back on the Vindex, and was too far from land for a safe return, he had to ditch his Scout D in the ocean after the unsuccessful attack.
One attempt to arm RFC Bristol Scouts with a synchronizable machine gun, like the air-cooled version of the Maxim-type Vickers machine gun that would later be used with great success on the contemporary Sopwith Pup fighter, was first tried with the late production RFC Scout C No.5313 in March 1916, and even though six other Scouts, both late Scout Cs and early Scout Ds, were tried out with the same setup as No. 5313 had used, the bulky Vickers-Challenger synchronizing gear used on all these Scouts seemed to have trouble in safely firing the Vickers guns-in May 1916 one of these Scouts fired every bullet from its Vickers gun through the propeller in testing.
Not one of the RFC or RNAS squadrons that ever received Bristol Scout aircraft was ever equipped "entirely" with the aircraft, and by the end of the summer of 1916 no new Bristol Scout aircraft were being supplied to the British squadrons of either service, often being replaced in RFC service with the Airco DH-2 single seat "pusher" fighter. A small number of Bristol Scouts did end up being based in the Middle East (in Egypt, Macedonia, Mesopotamia, and Palestine) in 1916 with the last known Bristol Scout in military service being the former RNAS Scout D No. 8978 in Australia, which was based at Point Cook, near Melbourne, as late as October 1926.
Many of the remaining Bristol Scout C & D aircraft that were no longer in front line service in the later years of WW I, however, remained with military units as "sporting" aircraft-not unlike what their original purpose would have been had "the Great War" not forced them into combat-and their light-handed, delightful flying characteristics, which were much like those of the Sopwith Pup, made them favorites of British military pilots for joyriding in, well away from the Front, for the remaining years of World War I.
[edit] Operators
[edit] Specifications (Bristol Scout D)
General characteristics
- Crew: One (pilot)
- 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: 198.00 ft² (18.40 m²)
- Empty weight: 789 lb (358 kg)
- Loaded weight: 1,195 lb (542 kg)
- Powerplant: × Le Rhône 9C piston, 80 hp () each
Performance
- Maximum speed: 94 mph (151 km/h)
- Rate of climb: 21 min 20 sec to 10,000 ft (21 min 20 sec to 3 048 m)
- Power/mass: 0.067 hp/lb (0.11 kW/kg)
Armament
1 Lewis or Vickers machine gun
[edit] References
- Bruce, J. M. (1994). Windsock Datafile No.44, The Bristol Scouts. Albatros Publications. ISBN 0-948414-59-6.
