Hely flew a twin - engined de Havilland Dragon Rapide ( serial number A3 - 2 ) .
Hely departed Richmond on 11 April for Port Hedland , which was to be the flight 's base for its initial survey work in Western Australia .
Flying a twin - engined de Havilland Dragon Rapide ( serial number A3 - 2 ) , Hely departed Richmond on 11 April for Port Hedland , which was to be the flight 's base for its initial survey work in Western Australia .