During the 1950s, the British Air Ministry drew up its plans for "Operational Requirement F.155" ("O.R. F.155") calling for a new breed of high-speed, high-flying interceptor aircraft to be powered by turbojet or rocket technologies (or a mix of both). The threat-of-the-day was the mighty Soviet Union and its long-range strategic, nuclear-capable bomber force so getting interceptors into the air as quickly as possible was the call-of-the-day for the major players in Western Europe. One of the design projects to come out of the period became Hawker Aircraft's "P.1103" designed by none other than Sir Sydney Camm - chief designer of the classic prop-driven, World War 2-era Hawker "Hurricane" fighter and jet-powered, Cold War-era Hawker "Hunter" fighter.
The project originated in 1955 and had the goal of producing an airframe capable of Mach 2+ speeds, an operating ceiling of up to 60,000 feet, and an in-built missile-carrying capability. Radar would be part of the aircraft's inherent makeup requiring a second crewman to cover the proposed workload made up of piloting, navigation, and weapons/radar management.
The work by Hawker produced an aircraft largely rooted in the original Hunter jet fighter and designed to a very compact structural form. Power was to come from a single afterburning turbojet engine which further helped to keep the design as small as possible and the crew of two would be seated in tandem over the nose of the aircraft. As the nose was to house the intended radar unit so the air intake for the air-breathing turbojet engine was positioned ventrally just under the cockpit floor while the unit would be exhausted by way of a conventional port under the tail at the rear. Wing mainplanes were broad surfaces set near midships and given sweepback (40 degrees) at the leading edges. To each member would be added a wingtip hardpoint for carrying an Air-to-Air Missile (AAM). The tail unit was very "Hunter-like" in shape and arrangement, sporting a single vertical plane with mid-mounted horizontal planes. The body of the aircraft would be comprised mainly of light alloys showcasing excellent streamlining for aerodynamic efficiency.
The end result, as proposed, was a clean, sleek offering centered around a less complex single-engine arrangement. For the required power, the aircraft would be outfitted with the still-in-development de Havilland "Gyron" afterburning turbojet engine offering 20,000lb thrust on dry and 25,000lb thrust with reheat engaged. To aid overall intercepting performance, the aircraft was also slated to house optional rocket boosters at the mid-span point of the mainplanes offering an additional 2,000lb of thrust each. The rocket boosters would provide less than four minutes of burn time but give the aircraft level flying speeds reaching Mach 2.0. Beyond this, the interceptor was to be capable of reaching the required 60,000 foot operating ceiling (68,000 ft estimated) and sport a rate-of-climb of 61,000 feet-per-minute - getting airborne in short order.
The missiles - the primary and only armament afforded to the aircraft - became 2 x Red Top, Red Hebe, or Blue Jay AAMs. The infrared homing Hawker "Red Top" was in-development and would not enter service until 1964 while the radar-guided/radar-homing Vickers "Red Hebe" was eventually cancelled during its development phase. The rear-aspect infrared de Havilland "Blue Jay" ("Firestreak") made it into service in 1957. In any case, the missiles would be supported by the onboard radar fit in the nose.
As completed, the proposed interceptor had an overall length of 63 feet, a wingspan of 39 feet, and a height of 15.5 feet. Maximum Take-Off Weight (MTOW) was estimated to reach 42,000lb with the missiles (Red Hebe variety) loaded.
Due to changing circumstances and requirements in the tumultuous 1950s period, a period which saw the infamous 1957 "Defence White Paper" defense review released, the P.1103 joined other British "paper airplane" designs in falling victim to a focus on Inter-Continental Ballistic Missiles (ICBMs) and a perceived shift to low-level bombers by the enemy - thus rendering high-altitude, high-speed manned interceptors moot. As such, the P.1103 only made it to the design study phase for its part in British aero-history.