During 1943, following its success in rapidly designing and mass-producing the
Boomerang fighter for the
Royal Australian Air Force (RAAF), CAC began design work on a fully-fledged
interceptor and
escort fighter. Because the Boomerang had become more and more obsolete against Japanese fighters like the
Mitsubishi A6M Zero, Sir
Lawrence Wackett (as head of CAC) proposed designing a new high-performance fighter from scratch.
Fred David, who had designed the Boomerang, was to lead an in-house design team at CAC. In June 1943, the design concept proposal was approved by the government and RAAF, which issued specification
2/43, enabling work to commence. The design was inspired by contemporary fighters – especially the German
Focke-Wulf Fw 190, details of which were available to the designers through Allied intelligence reports on captured aircraft. Although the CA-15 bore a superficial resemblance to the
North American P-51 Mustang, the CAC design was not based directly on the American aircraft and had quite different performance objectives. causing further delays in development, and it was decided to fit an in-line
Rolls-Royce Griffon Mk 61 (2,035 hp/1,517 kW). Engines for a prototype were leased from Rolls-Royce. It was intended that any production engines would have a three-stage
supercharger. ==Operational history==