The CAC Boomerang was the only Australian designed combat aircraft to see service during World War. It was designed as a stop-gap measure after the Japanese attack on Pearl Harbor found Australian territory itself under threat when its most modern fighters were a few US-supplied Buffaloes. Given the lack of experience, the design team led by Lawrence J. Wackett was forced to base the new aircraft on the earlier Wirraway trainer and the only avilable engines, US Twin Wasps. The result was an extremely rugged and maneuverable aircraft which neverthless suffered as a fighter due to its slow speed and poor altitude performance at a time when superior fighters like the P-40 were already in widespread use. Therefore, it ended up serving mostly as target markers for heavy bombers and in the army co-operation role where it performed admirably in the South Pacific.

The first CA-12 took to the air on 29 May 1942 with deliveries to training units beginning late that same year. These were followed by the improved C-13 with minor changes, the CA-19 tactical reconnaissance aircraft, and finally the CA-14 with turbocharged engines of which only one was built.