Armstrong Siddeley Motors: Notes of a meeting at Hawkers (Kingston)

Designation of Hawker Hunter sub-types: Mk.1 Original Hunter design with 45 deg sweep-back and an Avon 7,500 lb engine. Mk.2 same airframe as Mk.1, but adapted for a Sapphire Sa.6 engine. Mk.3 Mk.1 fuselage with 50 deg sweep-back wing and an Avon RA.14 engine. Mk.4 re-designed fuselage of larger diameter with 50 deg sweep-back wing and a Sapphire Sa.7 engine. The Mk.4 fuselage has to be redesigned to incorporate a main spar with sufficient clearance to accommodate the Sapphire Sa.7 engine. Hunter Mk.4: Mr Camm stated that the MoS had ordered a Mk.3 prototype and have asked Hawker to give a report on a further possible variant, namely the Mk.4