Editing Bristol Beaufighter (section)

==Design==
[[File:Air Ministry Second World War Official Collection CNA3943.jpg|thumb|upright=1.3|A Bristol Beaufighter, with "arrowhead", [[dipole antenna#Folded dipole|folded twin-dipole]] antenna on the nose for its VHF-band AI radar.]]
The Bristol Beaufighter is a fighter derivative of the Beaufort torpedo-bomber. It is a twin-engine two-seat long-range day and night fighter.<ref name = "moyes 16">Moyes 1966, p. 16.</ref> The aircraft employed an all-metal [[monocoque]] construction, comprising three sections with extensive use of 'Z-section' frames and 'L-section' [[longeron]]. The wing of the Beaufighter used a mid-wing [[cantilever]] all-metal monoplane arrangement, also constructed out of three sections.<ref name = "moyes 16"/> Structurally, the wing consisted of two [[Spar (aeronautics)|spars]] with single-sheet webs and extruding flanges, completed with a stressed-skin covering, and had metal-framed [[aileron]]s with fabric coverings along with [[hydraulically]]-actuated [[Flap (aeronautics)|flaps]] located between the fuselage and the ailerons.<ref name = "moyes 16"/> Hydraulics were also used to retract the independent units of undercarriage, and the brakes were actuated [[pneumatically]].<ref name = "moyes 16"/>

[[File:255 Squadron RAF Beaufighter MK II at RAF Hibaldstow Sept 1941.jpg|thumb|upright=1.3|left|A Merlin-powered Beaufighter night fighter Mk.II of [[No. 255 Squadron RAF]] at [[RAF Hibaldstow]] in Lincolnshire, September 1941. The Merlin [[Power-egg|power plants]] are an early type incorporating exhaust ducting to conceal the exhaust flames for night use, a method later superseded by simple exhaust shrouds]]
The twin Bristol Taurus engines of the Beaufort, having been deemed insufficiently powerful for a fighter, were replaced by more powerful two-speed supercharged Bristol Hercules [[radial engine]]s. These powered three-bladed [[Rotol]] [[constant-speed propeller]]s; both fully [[Propeller (aeronautics)#Feathering|feathering]] metal and wooden blades were used.<ref name = "moyes 16"/> The extra power had presented vibration issues during development; in the final design, the engines were mounted on longer and more flexible struts, which extended from the front of the wings. This change moved the [[centre of gravity]] (CoG) forward, which was undesirable, so the CoG was moved back by shortening the nose, which was possible as the space within the nose had been occupied by a [[bomb aimer]] in the original Beaufort torpedo bomber, unnecessary in a fighter. The majority of the fuselage was positioned aft of the wing and, with the engine cowlings and propellers now further forward than the tip of the nose, gave the Beaufighter a characteristically stubby appearance.<ref name = "moyes 3"/>

[[File:The navigator of a No. 125 Squadron Bristol Beaufighter MK VIF settles into his position, ready for another night patrol from Exeter, 14 September 1943. CH11182.jpg|thumb|Navigator position]]
In general, with the exception of the powerplants used, the differences between the preceding Beaufort and Beaufighter were minor. The wings, control surfaces, retractable landing gear and aft section of the [[fuselage]] were identical to those of the Beaufort, while the wing centre section was similar apart from certain fittings. The areas for the rear gunner and bomb-aimer were removed, leaving only the pilot in a fighter-type cockpit. The navigator-radar operator sat to the rear under a small [[Perspex]] bubble where the Beaufort's dorsal turret had been. Each crew member had his own hatch in the floor of the aircraft. The front hatch was behind the pilot's seat, whose back collapsed to allow the pilot to climb over and into the seat. In an emergency, the pilot could operate a lever that remotely released the hatch, grasp two steel overhead tubes and lift himself out of his seat, swing his legs over the open hatchway, then let go to drop through. Evacuating the aircraft was easier for the navigator, as the rear hatch was in front of him and without obstruction.<ref name="White2006">White 2006, pp. 62–64.</ref><ref name = "moyes 5 16">Moyes 1966, pp. 5, 16.</ref>

The Beaufighter's armament was located in various positions on the lower fuselage and wings. The bomb bay of the Beaufort had been entirely omitted, but a small bomb load could be carried externally. A total of four forward-firing 20&nbsp;mm [[Hispano-Suiza HS.404|Hispano Mk.I cannon]] were mounted in the lower fuselage area. These were fed from 60-round drums, requiring the radar operator to change the ammunition drums manually—an arduous and unpopular task, especially while chasing a bomber at night.<ref name = "moyes 5 6">Moyes 1966, pp. 5–6.</ref> They were soon replaced by Hispano Mk. II cannon featuring a belt-feed system.<ref name = "moyes 6">Moyes 1966, p. 6.</ref>  The cannons were supplemented by six [[.303 in]] (7.7&nbsp;mm) [[M1919 Browning machine gun|Browning]] machine guns in the wings (four starboard, two port, the asymmetry caused by the port mounting of the landing light).<ref>[http://www.squadron.com/reviews/review-tm61053.htm Bristol Beaufighter VI] squadron.com  {{webarchive |url=https://web.archive.org/web/20120317030427/http://www.squadron.com/reviews/review-tm61053.htm |date=17 March 2012 }}</ref> This was one of the heavier, if not the heaviest, fighter armament of its time.<ref>{{cite web|title=Bristol Beaufighter – Variants and Stats |url=http://www.historyofwar.org/articles/weapons_beaufighter_variants.html |publisher=History of War |access-date=27 October 2015}}</ref><ref>Its armament was exceeded by the gunship variants of the US [[North American B-25 Mitchell]] and [[Douglas A-26 Invader]] medium bombers</ref> When Beaufighters were developed as fighter-torpedo bombers, often with the machine guns removed, they used their firepower to suppress [[flak]] and hit enemy ships, especially escorts and small vessels. The recoil of the  guns could reduce the speed of the aircraft by around 25 knots.<ref name="Bradley2010" />

The Beaufighter was commonly operated as a [[night fighter]], such as during the [[Battle of Britain]]. Mass production of the type came at almost exactly the same time as the first British [[aircraft interception radar]] sets were becoming available, a natural match for a night fighter. As the aircraft's  four 20&nbsp;mm cannons were mounted in the lower fuselage, the vacant nose could accommodate the radar antennas needed, and while early aircraft interception equipment was too bulky to fit in single-engine fighters of the day, it could be accommodated in the Beaufighter's spacious fuselage. At night the onboard radar enabled the aircraft to detect and locate enemy aircraft. The heavy fighter remained fast enough to catch up to slower German bombers and, with its heavy armament, deal out considerable damage to them.<ref name = "moyes 3"/> While early radar sets suffered from restrictions in range and thus initially limited the aircraft's usefulness, improved radars became available in January 1941, making the Beaufighter one of the more effective night fighters of the era.<ref name = "moyes 10"/>