Incident Overview
On a charter flight from Adelaide to Moomba and Dullingari, a twin-engine aircraft operated by an unnamed company encountered a critical loss of engine performance shortly after takeoff from Moomba Airport. The aircraft, registered VH-DVX, was subsequently destroyed by fire after a forced landing. The pilot and two passengers escaped, while a third passenger could not be rescued.
Flight Details
The flight from Adelaide to Moomba proceeded without incident. After landing, the pilot parked adjacent to the refueling cabinets, assisted passengers from the aircraft, and removed baggage from the nose locker. During this time, a conversation occurred between the pilot and the aircraft refueler. The exact content could not be determined, but it appeared the pilot did not specify the fuel type, only which tanks were to be filled.
Fueling
While the refueler fueled the aircraft, the pilot accompanied passengers to the terminal. Upon return, the pilot signed a fuel release note indicating 263 liters of Jet A-1 (aviation turbine fuel) had been supplied. He then checked the fuel tanks for water contamination, noting the sample appeared free of water and resembled the normal fuel (AVGAS) used by PA-31 aircraft.
Sequence of Events
The pilot and passengers boarded, engines were started, and the aircraft taxied for departure on runway 12. Pre-takeoff checks, including engine temperature and pressure readings, were completed and reported normal. The takeoff was initially normal; after gear retraction, power was reduced to standard climb settings. At approximately 500 feet above ground level, the pilot sensed a performance loss, with indicated airspeed at 115 knots—5 knots below normal. Airspeed then further decayed, accompanied by engine surging and rough running. Unable to diagnose the problem, the pilot initiated a turn back toward the aerodrome. Shortly after the turn began, the right engine misfired and propeller feathering was initiated. Airspeed dropped to 85 knots, with a high rate of sink, and the pilot realized impact was imminent.
Accident and Rescue
The aircraft first struck the ground with the right wing, then the nose, before the fuselage made heavy contact in a flat attitude. It slid approximately 45 meters before coming to rest and caught fire during the impact sequence, becoming completely burnt out. The pilot and two passengers escaped from the wreckage; attempts to assist the third passenger were thwarted by the fire.
Investigation and Probable Cause
The investigation established that Jet A-1 fuel had been added to the fuel tanks of VH-DVX, comprising approximately 68 percent of the total fuel. The engines fitted to this aircraft are not compatible with Jet A-1 fuel. The probable cause is that the aircraft was fueled with an incorrect fuel type, leading to engine performance degradation and the subsequent forced landing.