CAC Wirraway - Development

Development

Three Royal Australian Air Force officers, led by Wing Commander Lawrence Wackett, were sent on an overseas evaluation mission in 1936 to select an aircraft type for local production in Australia. The aircraft selected was the North American Aviation (NAA) NA-16. Production licences were obtained in 1937 and two NA-16s were purchased from North American Aviation to act as prototypes. The first of these two aircraft was the fixed undercarriage NA-16-1A (similar in design to the BT-9); the second was the retractable undercarriage NA-16-2K (similar to the BC-1). These two aircraft were also known by their NAA project accounting codes (NA-32 for the NA-16-1A and NA-33 for the NA-16-2K) sometimes leading to confusion. These accounting codes (or "charge" codes) were used internally by NAA to track their projects and were not the actual aircraft model numbers. The NA-16-1A arrived in Australia in August 1937 and following assembly flew for the first time at Laverton on 3 September of that year, exactly two years before war was declared on Nazi Germany by the United Kingdom and France. The NA-16-2K arrived in Australia in September 1937 and likewise flew shortly afterwards. These aircraft were given the RAAF serials A20-1 and A20-2 within that organisation's numbering system.

The NA-16-2K was the type selected for production. With several detail and structural changes, such as provision for two forward-firing guns instead of the NA-16's one, and strengthened structure to allow dive-bombing operations, the first CA-1 Wirraway, RAAF serial A20-3, made its maiden flight on 27 March 1939. This aircraft was kept by CAC for testing for several months and the first two Wirraways delivered to the RAAF were A20-4 and A20-5, on 10 July 1939. By the outbreak of World War II the RAAF had received a total of six Wirraways. Forty CA-1 Wirraways were built before the CA-3 entered production. Although there were detail changes to the design, the change in designation had more to do with the next batch of Wirraways being built to a different government contract than any real difference between the two sub-types. The CA-5, CA-7, CA-8 and CA-9 were all broadly similar to the CA-3 and it was only the CA-16 that had substantial design changes. These included wing modifications to allow a heavier bomb load and dive brakes for dive-bombing. Sets of 'dive bomber' wings (as fitted to the CA-16) were built under the designation of CA-10A (the CA-10 being a dive-bomber variant that was not built) and retrofitted to CA-3s, −5s, −7s and −9s; 113 Wirraways were converted. Seventeen Wirraways were modified post-war and delivered to the Royal Australian Navy (RAN), the modifications were incorporated under the CAC designation CA-20. The 17 included a CA-1, a CA-5 and numbers of all subsequent variants and operated under their RAAF serials. Production continued until after the end of World War II; CA-16 A20-757; the last of 755 Wirraways built, was delivered to the RAAF in July 1946.