ATSB: Fuel Crosscheck Failures Preceded Flylink Diamond DA20 Precautionary Landing at Toowoomba Wellcamp
Why It MattersThe findings put routine fuel verification and defect-tracking discipline at flight-training operators in the spotlight, a recurring exposure for light piston fleets whose fuel gauges are often discounted by pilots.
The Australian Transport Safety Bureau (ATSB) has released its final report on a 5 December 2025 incident involving a Diamond DA20 single-engine training aircraft operated by Flylink Aviation College. The aircraft was on a training flight from Archerfield Airport, Queensland, with a student and an instructor pilot on board. Towards the end of the 2-hour flight, while approaching the planned destination of Toowoomba City Aerodrome, the engine power reduced momentarily and then restored. A second similar cycle followed, after which the instructor took control and diverted to Toowoomba Wellcamp for a precautionary landing.
The ATSB could not determine whether the engine issues were caused by a failing fuel supply or a pre-existing engine defect. It concluded that fuel management discrepancies meant the instructor and student did not identify when the fuel on board fell below the required final reserve. Before the flight, the instructor and student each measured the fuel with the aircraft's dipstick and recorded between 70 and 74 litres, significantly more than the 61 litres measured at the end of the previous flight, even though no fuel had been added. The investigation also found that the fuel calibration card required under Australian regulations was not present in the aircraft. One other Flylink DA20 was also missing a calibration card, and the operator has since rectified this in both aircraft.
ATSB Director of Transport Safety Graham Drummond said that while some pilots dismiss fuel gauges in piston-driven aircraft as inaccurate, they are often the only way to independently verify fuel quantity against a pre-flight measurement, and sole reliance on one method of fuel assessment leaves an operation vulnerable to fuel exhaustion or starvation. He reminded operators and owners to maintain the fuel quantity indicating system to the regulated standard, including displaying a fuel calibration card when required.
The ATSB could not rule out an engine defect, partly because the operator mainly used an informal process for raising and tracking defects, preferring face-to-face and phone communication. This made managing repetitive defects, including an ongoing intermittent engine-related defect, more difficult. Flylink Aviation College is updating its procedures to improve the recording and tracking of defects across its fleet.
