Forced/precautionary landing involving a Hiller Aviation UH-12E, VH-LUN, 10 km north-west of Dorrigo, New South Wales, on 21 April 1998

During a property inspection prior to commencing spraying, the engine failed. The helicopter was about 700 ft above ground level at the time. The pilot attempted to dump the load by the electrical system, but this failed to operate. He was too occupied to operate the mechanical dump system.

During the subsequent landing, the helicopter rolled onto its side after a cross tube on one side failed. The failed area had been weakened by corrosion and there was evidence of pre-existing cracks. The engine crankcase was fractured, consistent with a connecting rod failure at no. 5 cylinder. Logbook records indicated that the engine had been over-sped some 200 operating hours earlier. A faulty canon plug had prevented the electrical dump system from operating.