The Swift F 3 and F 4 fighters were noted to have improved performance over their predecessors; the F 4 would be the last variant that the RAF would accept in the interceptor role. All fighter variants of the Swift were withdrawn from service by the RAF, after a short time in service, to be replaced by the more capable Hawker Hunter. While subject to its own problems, the Hunter had quickly proved to be a successful fighter aircraft. By autumn 1954, the issues with the Swift had become public knowledge and reports of the pending cancellation of the Swift were being printed by the national press; Under-Secretary of State for Air Sir George Ward stated of the aircraft in Parliament that: "Aerodynamic difficulties have been encountered, and it is not possible to say with certainty if they can be overcome in version under development".