What happened
On 2HM August 2025, a Piper Aircraft PA-28 was participating in the fourth stage of the Outback Air Race, flying from Daly Waters Airport to RAAF Base Tindal in the Northern Territory. Before departure, the pilot identified a faulty alternator. A maintenance engineer encouraged the flight to proceed by charging the battery, but failed to calculate if the battery capacity could sustain the flight duration.
During the flight, the aircraft's electrical power failed, leaving the pilot unable to communicate with Air Traffic Control (ATC) via radio. Despite being in visual meteorological conditions and near Homebush Park ALA, the pilot did not divert to the nearest suitable airport. Instead, the pilot entered controlled airspace at Tindal, incorrectly believing they had priority. This led to the aircraft being on final approach in close proximity to a Lockheed Martin F-35 approaching the same runway. The tower controller failed to detect the PA-28 during a visual check of the fighter jet's approach path.
The investigation
The investigation examined the maintenance performed prior to the flight, the pilot's decision-making, and the actions of ATC. It was found that the maintenance engineer did not assess the expected electrical load or the battery's endurance for the planned route. Furthermore, the engineer failed to document the alternator fault or the work performed in the maintenance release, violating legislative requirements.
Regarding flight operations, the pilot was aware of the increased risk due to the faulty alternator but had not established contingency plans for a total electrical failure. While the pilot attempted to use a group chat to relay information to ATC, they did not follow the instruction to remain in non-controlled airspace. The investigation also noted that the pilot likely failed to monitor the aircraft's ammeter effectively, which would have indicated the alternator was not functioning.
Findings
- The maintenance engineer encouraged the flight to proceed without verifying if the battery could support the electrical load.
- No entry was made in the maintenance release regarding the alternator issue or the battery charging.
- The pilot lacked contingency planning for a loss of electrical power.
- The pilot did not effectively monitor the aircraft's electrical system during flight.
- The pilot entered controlled airspace without clearance and failed to divert to the nearest suitable airport as per emergency procedures.