Kawasaki Bell 47, VH-HFV, 35 km east of Elsey Station, Northern Territory, on 29 November 1989

Circumstances:

The aircraft was cruising at about 150 - 200 feet above the trees over heavy scrub country when the engine coughed. The pilot started a descent and the engine regained power briefly before stopping completely. Unable to reach a suitable area for an autorotational landing, the pilot avoided two large trees before the aircraft crashed through smaller trees and struck the ground. The aircraft had been operating for some two and one half hours since refuelling to full tanks, which usually provided an endurance of at least three hours. The pilot was in the habit of managing his fuel by reference only to the operating times and by landing to conduct a sight check of the fuel tank contents after about two and one half hours of operations. No reliance was apparently placed on the fuel contents gauge in the aircraft. An inspection of the aircraft after the accident revealed fuel stains over the oil tank, induction plate and main frame. The inspection also revealed that two screws were missing from the carburettor drain tap plate. No signs of the fuel leak were reportedly evident at the previous pre-flight inspection.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Pilot relied on the times of operation for fuel management in flight and did not refer to the fuel contents gauge in the aircraft.
2. Leaking carburettor fuel drain tap.
3. Engine failure through fuel exhaustion.
4. Engine failure over terrain unsuitable for an autorotational landing.