Vickers F.B.11

The Vickers F.B.11 was a prototype British three-seat escort fighter of the First World War, a large single-engined biplane that carried one gunner in a nacelle on the upper wing for an all-round field of fire. Only one example was completed. In early 1916 the British War Office drew up a specification for a multi-seat escort fighter powered by a Rolls-Royce Eagle engine, to protect bomber formations from fighters such as the Fokker E.I and to destroy enemy airships; orders for prototypes went to Armstrong Whitworth, Sopwith and Vickers. The Vickers response, designed by R. L. Howard-Flanders, was a single-bay tractor biplane with the pilot and one gunner in closely spaced cockpits under the upper wing trailing edge and a second gunner in a nacelle, or fighting top. It flew in autumn 1916, had poor lateral control and performance and was destroyed in a crash. Effective synchronising gears were by then available, so none of the escort fighters were developed further.