Thursday, August 4, 2011

Britain - 1913 Vickers EFB 1-3

Early Evolution of Dedicated Fighters

The British Admiralty began the search for a viable fighter before the start of the Great War. One of the companies approached to design them was the Vickers Ltd Aviation Department. Even though Vickers was unsuccessful in developing a real fighter aircraft at that time, the research lead to the development of the E.F.B.5 and F.B.5 Gunbus which proved to be an effective aircraft for its time.

Vickers Experimental Fighting Biplane 1 - 1913

Vickers E.B.1 - 1913
Vickers E.B.1 - 1913

Vickers received a contract from the Admiralty on November 19, 1912 for an experimental fighting biplane armed with a machine gun. Vickers investigated various configurations before deciding on placing the gunner in the extreme nose of the aircraft, in order to achieve a clear field of fire and avoid the still unsolved problem of firing a machine gun through the propeller's arc. Designated E.F.B. or Experimental Fighting Biplane 1 the aircraft was also known as the "Destroyer". Even though the prototype was unsuccessful; the Vickers E.F.B.1 was, if not the first, then one of the earliest dedicated fighter aircraft ever built.

The design choice required a fuselage nacelle carrying an 80 hp (60 kW) Wolseley Vee-eight-cylinder engine driving a pusher propeller mounted in the rear. The nacelle was built from steel tubing with a duralumin skin. This nacelle was mated with an unequal-span heavily-staggered biplane configuration. Wing warping was employed for lateral control. The airframe of the E.F.B.1 was primarily an all metal construction. The tail surfaces were carried by a pair of vertically disposed booms attached to the upper and lower rear wing spars on each side of the engine. The Vickers E.F.B.1 was armed with a single 7.7mm Maxim machine gun on a mount allowing a 60° range of elevation and lateral traverse.

Prior to its first flight, the E.F.B.1 was displayed at the Aero Show held at Olympia, London, in February 1913. The gun was fitted for the first flight test, made at Joyce Green, but this rendered the aircraft so nose-heavy that it briefly left the ground, then nosed down, struck the ground and turned over.

Vickers Experimental Fighting Biplane 2

Vickers E.B.2 - 1913
Vickers E.B.2 - 1913

Following the loss of the E.F.B.1, Vickers undertook major redesign of its gun carrier while retaining the basic configuration to result in the E.F.B.2, again against an Admiralty contract. The E.F.B.2 eliminated the wing stagger of the previous aircraft and increased the span of the lower wing while retaining warping for lateral control. The fuselage nacelle was redesigned and large celluloid windows were inserted in its sides; the angular horizontal tail surfaces gave place to surfaces of elliptical form and a 100hp Gnome Monosoupape nine-cylinder rotary engine was fitted. The 7.7mm machine gun on a ball-and-socket mounting in the forward cockpit was retained, and the E.F.B.2 entered flight test at Bognor in the autumn of 1913, but crashed there during the course of October.

Vickers Experimental Fighting Biplane 3 - 1913

Vickers E.B.3 - 1913
Vickers E.B.3 - 1913

In December 1913, a third Vickers Experimental Fighting Biplane, the E.F.B.3, made its debut. The slight overhang of the top wing was eliminated to result in an equi-span biplane, the fuselage nacelle underwent further redesign, the celluloid windows being eliminated, and, most important, ailerons on both upper and lower wings supplanted the wing-warping control of its predecessors. The 100hp Gnome Monosoupape rotary was retained as was also the 7.7mm Vickers gun. Displayed at the Aero Show held at Olympia in 1914, the E.F.B.3. was the subject of an order from the Admiralty for six aircraft placed in December 1913. This contract was subsequently taken over by the War Office, the six aircraft embodying a number of modifications - at least one was fitted with an eight-cylinder Vee-type 80hp Wolseley engine - and being referred to as the Vickers No (or Type) 30. These were to lead in turn to the E.F.B.5 and F.B.5 Gunbus.

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