On 23 October 1975 Hawker Siddeley Heron DH114 2E/A1 aircraft, registered VHCLS, with a crew of three and eight passengers aboard, departed Mount Isa, Queensland, for Cairns on a regular public transport service. The flight proceeded to the vicinity of Cairns without reported incident and at 1917 hours Eastern Standard Time (EST) it was cleared for, and acknowledged instructions for an ILS (instrument landing system) approach to Runway 15 at Cairns Airport. At 1926 hours the flight reported 'going round' and, at about this time a number of people located at various positions to the north of the airport observed an aircraft manoeuvring at a low height. Shortly afterwards the aircraft crashed at a point 2813 metres north-west of the threshold of Runway 15. Heavy rain and lightning were in the general area of the accident site. The aircraft was virtually destroyed, and all of its occupants were killed as a result of the accident.