After this accident it was recommended to implement pre-flight safety demonstrations for over-water flights. 16 April 1952 de Havilland Australia DHA-3 Drover 0 16 April 1952: the de Havilland Australia DHA-3 Drover VH-DHA operated by the Australian Department of Civil Aviation[6] with 3 occupants was ditched in the Bismarck Sea between Wewak and Manus Island.