This flight was the last of a multi-stage flight from Rockhampton. A dip stick was used to determine the quantity of fuel on the aircraft prior to refuelling for the flight. One tank was again checked after refuelling and the pilot was satisfied that sufficient fuel was carried. He was in the habit of disregarding the fuel gauges as being inaccurate. Both engines subsequently failed towards the end of the flight, however, the pilot was able to carry out a successful forced landing on a nearby strip. An inspection of the aircraft fuel system revealed that only unuseable fuel remained in the aircraft fuel tanks. A fuel system calibration showed that the gauges were accurate and that the dip stick was over-reading by about 15 US gallons (57 litres). This resulted in the fuel onboard being insufficient to complete the flight. The dip stick had been with the aircraft when it was imported some six years earlier.