Design The CAC Wirraway was a training and general purpose military aircraft. The fuselage comprised a welded framework composed of chromium steel, which was constructed from four separately produced sections bolted together during final assembly. The sides of the fuselage featured fabric covering supported by aluminium alloy frames, while the underside and decking has metal coverings instead. The single-spar wings, which were built in five individual sections, were composed of spaced ribs and a stressed skin. The control surfaces were metal-framed with fabric covering; the split-flap arrangement of early Wirraways were supplemented on later-built aircraft via the addition of dive brakes. An all-metal stressed skin construction was used for the tailplane and fin; both sides of the tailplane were interchangeable. The Wirraway was powered by a single 600 hp Pratt & Whitney R-1340 Wasp radial engine, licence-built by CAC and allowing the aircraft to reach speeds of up to 191 knots. The engine drove a three-bladed variable-pitch propeller developed by de Havilland Propellers. Fuel was stored within a pair of 45 gallon tanks. The two-man crew sat within a tandem cockpit, complete with a fully enclosed sliding canopy; both positions were fitted with flying controls. In addition, the rear cockpit featured a rotatable folding seat for the gunner/bomb-aimer, as well as a prone bombing position in the floor of the aircraft. The Wirraway could carry a light armament of a single 500 lb bomb or a pair of 250 lb bombs under the wings; light bombs or flares could also be carried underneath the centerline section. Additionally, a pair of forward-firing Vickers Mk.V machine guns were fitted along with a single swivel-mounted machine gun positioned at the rear of the cockpit. A later variant (CA-16) received strengthened wing struts, which allowed the installation of four 250lb or two 500lb and two 250lb bombs. The Wirraway could also carry two 200lb storepedos fitted with parachutes which were used to deliver supplies and munitions to troops in the field. Operational history Wartime service In June 1939, in light of the declining situation in Europe and the increasing likelihood of a major conflict, the Chief of the Air staff recommended the expansion of the RAAF to a total of 32 squadrons; of these, preparations for 9 general purpose squadrons, which were intended to be equipped with the Wirraway, were immediately put into motion. On 25 August 1939, one month after the first deliveries