The Wirraway fighters which had proved inadequate at Rabaul .
Darwin were replaced by Bell P - 39 Airacobras , and Townsville 's aerial defence was supplemented by RAAF and USAAF Curtiss P - 40 Warhawks .
The Wirraway fighters which had proved inadequate at Rabaul and Darwin were replaced by Bell P - 39 Airacobras , and Townsville 's aerial defence was supplemented by RAAF and USAAF Curtiss P - 40 Warhawks .