The Fibber was an attempt to create an aircraft which could deliver a payload of bombs and hold off enemy fighters without the need for an escort. Early versions were successful, but mainly due to their speed. Eventually the Fibber proved to be a highly adaptable aircraft, with Bomber, pure fighter, Interceptor and Reconnaissance variants, as well as being developed into a jet fighter.

The Mk.2 featured a redesigned fuselage and cockpit. Engine power was increased and the aircraft's top speed was improved and it became capable as a long range fighter and interceptor aircraft. The Mark 2 would provide the basis for all future models.