On 31 December 2017 at about 3:15 pm AEDT (UTC+11:00), a de Havilland Canada DHC-2 Beaver configured as a floatplane crashed into Jerusalem Bay off Cowan Creek,[1] on the northern outskirts of Sydney, Australia.

Post mortem tests on the bodies of the victims showed raised levels of CO in the blood, and a crack in the exhaust system was seen as the likely source of the gas.

[4][5] The aircraft was a 54-year-old de Havilland Canada DHC-2 Beaver, originally built in 1963 and registered in Australia since February 1964; it was powered by a single Pratt & Whitney R-985 Wasp Junior engine.

[12] The intermediate report, published on 31 January 2018, indicated that the aircraft was found to have followed a differing flight path from the usual, and had failed to climb to the necessary altitude needed to fly over the surrounding terrain.

[5] On 28 January 2021, the ATSB released a final report into the accident, which concluded that the pilot and passengers had higher than normal levels of carboxyhaemoglobin in their blood.