The Blackburn Firebrand demonstrates the difficulties encountered by many aircraft manufacturers when developing new aircraft during the Second World War. When work began on the Firebrand in the spring of 1939 it was seen as a short-ranged two-man fleet interceptor, but ever-changing requirements meant that by the time it entered service in September 1945 it was a single seat torpedo-armed strike aircraft.
Work on the Firebrand began in response to Air Ministry specification N.8/39 of March 1939. This was one of two specifications issued at that time for a new two-seat short range carrier-borne fighter aircraft to replace the Blackburn Skua and Fairey Fulmar, already obsolescent when they entered service. N.8/39 called for an aircraft armed with four 20mm cannon in the wings, N.9/39 for one with a power-operated gun turret, as used on the Blackburn Roc and Boulton Paul Defiant.
Both specifications were modified during 1940. N.9/39 became N.5/40, for a two-seat fighter with wing guns, while N.8/39 became N.11/40, which simply removed the second crewman from the specification. N.11/40 thus called for the exact type of fighter that the Fleet Air Arm needed – a well armed modern single seat monoplane.
The first full-scale mock-up of the Firebrand was complete by September 1940, and the first prototype of the F.Mk I made its maiden flight on 27 February 1942. The original requirement for a two-seater aircraft was still visible in the size of the Firebrand, which was wider, longer and heavier than even the Chance-Vought F4U Corsair, the largest of the American carrier-borne fighters to see service during the Second World War.
One of the reasons for the size of the aircraft was the choice of the large but very powerful 2,305hp Napier Sabre III liquid-cooled twenty-four cylinder H-type engine to power the Firebrand. Work on the Sabre-powered Firebrand continued until the summer of 1943. Deck landing trials took place in February 1943, and armament trials in 1943, but by now the need for a fleet fighter was much reduced. American Wildcats (known as the Martlet in British service) and the fast but somewhat fragile Supermarine Seafire had filled the gap, while the Corsair would actually make its debut as a carrier based aircraft with the Royal Navy early in 1944.
In the summer of 1943 the Ministry of Aircraft Production decided to allocate all Sabre engines to the Hawker Typhoon. This ended any change of the Firebrand F.Mk I entering service as a fighter (nine F.Mk Is were produced), and left Blackburn needing to find a new engine for the aircraft. The Ministry of Aircraft Production found them a new purpose for it, as a fast carrier-borne torpedo bomber.
The prototype of the new T.F. Mk II made its maiden flight on 31 March 1943, and its first flight with a torpedo on 2 April, making it the first single-seat torpedo bomber in the world. Only twelve of the Sabre powered T.F. Mk IIs were produced.
The first production version of the Firebrand was the T.F. Mk III (T.F. standing for Torpedo Fighter). This was powered by a 2,400hp Bristol Centaurus VII two-row eighteen cylinder sleeve-valve radial engine. This new engine altered the profile of the Firebrand, which had been designed around longer but narrower inline engines. The Firebrand III also saw the early Spitfire-style canopy used on the Mk I and Mk II replaced with a tear-drop canopy, giving the aircraft a similar appearance to the Republic Thunderbolt. Twenty-seven T.F. Mk IIIs were completed, and most were used for testing.
The main production version was the T.F. Mk 4, which had a larger horn balanced rudder, which improved its handling at slow speeds. The Mk 4 was also equipped to act as a dive bomber, and could carry two 2,000lb bombs or sixteen 60lb rockets. 102 T.F. Mk 4s were built, and the first made its maiden flight on 17 May 1945, just as the war in Europe was coming to its end. The Firebrand T.F. Mk 4 was used to equip No.813 Squadron, which on 1 September 1945 became the first of only two front line squadrons to operate the aircraft (along with No.827 Squadron).
The last of the 220 Firebrands produced were T.F. Mk 5s, which only differed from the Mk 4 in detail. The Firebrand remained in service for eight years, operating from HMS Illustrious, HMS Implacable and HMS Eagle. They were finally phased out in 1953 in favour of the turbo-prop powered Westland Wyvern.
Stats (T.F. Mk 4)
Engine: Bristol Centaurus IX
Wing span: 51ft 3.5in
Length: 38ft 9in
Height: 13ft 3in
Tare weight: 11,689lb
All-up weight: 15,671lb
Maximum speed: 342mph without torpedo, 320mph with torpedo
Service ceiling: 34,000ft
Range: 754 miles