Vickers F.B.5

The first "pusher" to enter service during World War I was the Vickers Fighting Biplane 5. A two-seater, it was the first aircraft specifically designed as a fighter for the Royal Flying Corps. The first F.B.5 to reach France was delivered to 2 Squadron in February 1915 and 11 Squadron was equipped with F.B.5s in July 1915. Also known as the Vickers "Gunbus," it was armed with a moveable, forward-firing machine gun but it was vulnerable to attack from the rear.

Vickers F.B 5 "Gun Bus"
Gunbus of the RFC
Role	Fighter
Manufacturer	Vickers Limited
First flight	17 July 1914
Introduced	5 February 1915
Retired	1916
Primary users	Royal Flying Corps Aéronautique Militaire
Number built	224

The Vickers F.B.5 (Fighting Biplane 5) (known as the "Gunbus") was a British two-seat pusher military biplane of the First World War. Armed with a single .303 in (7.7 mm) Lewis Gun operated by the observer in the front of the nacelle, it was the first aircraft purpose-built for air-to-air combat to see service, making it the world's first operational fighter aircraft.

Design and development

Vickers began experimenting with the concept of an armed warplane designed to destroy other aircraft in 1912. The first resulting aircraft was the Type 18 "Destroyer" (Vickers E.F.B.1) which had been demonstrated in 1913. This aircraft was of the "Farman" pusher layout, to avoid the problem of firing through a tractor propeller, and was armed with a single belt-fed Maxim gun. The belt feed proved problematic for a flexible machine gun, and the weapon installed was changed to the lighter, handier, drum-fed .303 in (7.7 mm) Lewis gun. The E.F.B.1 was the first in a line of Vickers' "Experimental Fighting Biplanes", of which the F.B.5 was the most famous - and the first to be built in quantity.

The F.B.5 first flew 17 July 1914. It was powered by a single 100 hp (75 kW) Gnome Monosoupape 9-cylinder rotary engine driving a two-bladed propeller, and was of simple, clean, and conventional design compared with its predecessors. In total, 224 F.B.5s were produced, 119 in Britain by Vickers, 99 in France and 6 in Denmark.

F.B.6

The Vickers F.B.6 was a development of the F.B.5 with an increased span on the upper wing. Only one was built.

F.B.9

A further development of the F.B.5 the Vickers F.B.9 had a more streamlined nacelle and an improved ring mounting (either Vickers or Scarf) for the Lewis gun. 50 were delivered to Royal Flying Corps training units. A few served in some F.E.2b squadrons while they were waiting for their new aircraft in late 1915 - very early 1916.

Operational history

The first F.B.5 was delivered to No. 6 Squadron of the Royal Flying Corps (RFC) at Netheravon in November 1914.^[1] On 25 December 1914, the first use of the F.B.5 in action took place, when a F.B.5 took off from Joyce Green airfield to engage a German Taube monoplane, hitting the Taube (and possibly causing its loss) with incendiary bullets from a carbine after the Lewis gun jammed.^[2]

The F.B.5 began to be seen on the Western Front when the first examples reached No.2 Squadron RFC on 5 February 1915.^[3] The type served in ones and twos with several other units before No. 11 Squadron RFC became the world's first fighter squadron when, fully equipped with the F.B.5, it deployed to Villers-Bretonneux, France on 25 July 1915.^[4] Second Lieutenant G.S.M. Insall of 11 Squadron won the Victoria Cross for an action on 7 November 1915 in which he destroyed a German aircraft while flying a Gunbus.^[5] No. 18 Squadron RFC, which deployed to France in November 1915, also operated the F.B.5 exclusively.

The F.B.5's performance proved to be inadequate for its intended role; although its forward-firing machine gun was a great advantage, the fighter did not have the speed or rate of climb to pursue its quarry. By the end of 1915, it was outclassed by the Fokker Eindecker. Some examples of the improved Vickers F.B.9 were sent to France, pending sufficient supplies of the Royal Aircraft Factory F.E.2b, but the active career of the Gunbus was soon over. The remaining examples were mostly used as trainers.

Legacy

The Vickers company persisted with an active experimental program during the First World War period, including a line of single-seat pusher fighters, but the F.B.5 remained their only significant production aircraft until the Vickers Vimy bomber, which entered service too late to have an impact on the war.

Despite its moderate effectiveness, the Vickers F.B.5 did have a lasting legacy as German pilots continued to refer to British pusher aircraft as "Vickers-types". Many victories over D.H.2 or F.E.2b pushers were reported as destruction of a "Vickers".