Forced/precautionary landing involving a Cessna U206G, VH-AHX, 7 km south-west of Numbulwar, Northern Territory, on 15 January 1993

About 20 minutes into the flight the pilot detected a change in engine noise. Scanning the engine instruments, he noticed the manifold pressure and fuel flow indications had decreased and were continuing to fall slowly.

Application of full throttle and rich mixture had no effect, but when he changed fuel tanks, switched the emergency boost pump on, and check each magneto individually, the power decreased further. Leaning the mixture tended to increase power momentarily.

Retarding the throttle a small amount resulted in a substantial loss of power with the aircraft unable to maintain normal flight. After briefing the passengers and transmitting a "Mayday" call, the pilot carried out a forced landing into lightly timbered country. The aircraft was substantially damaged, but the pilot and passengers escaped uninjured.

Subsequent examination revealed that the throttle/mixture control cable support bracket had fractured, causing a loss of throttle movement between the cockpit control and the fuel control unit at the engine. The fracture was the result of a fatigue crack in the support bracket. The crack had propagated over a period of time.