Fuel contamination involving a Robinson R22 HP, VH-JWV, Mataranka No 1 Bore, Northern Territory, on 27 December 1993

The helicopter was being used to evacuate a workman from an outstation due to flooding in the area. The pilot, concerned about the deteriorating weather conditions, decided to add another 10 litres of fuel from a drum located at the outstation. The pilot reported that he checked the fuel tank drain finding no indication of water or contamination.

About 30 seconds after take-off the engine began to misfire badly and lose power, committing the pilot to a near vertical autorotational landing into a small hole in the relatively high timber. The autorotation was commenced from about 150 feet above ground level at about 30 knots airspeed, with a turn of 90 degrees required to reach the small clearing. The pilot was unable to reduce the subsequent high rate of descent even though full up collective pitch was applied from about 8 feet above the ground.

This resulted in a heavy landing causing substantial damage to the helicopter. Investigation revealed that the aircraft fuel system was contaminated with water.