Occurrence Briefs are concise reports that detail the facts surrounding a transport safety occurrence, as received in the initial notification and any follow-up enquiries. They provide an opportunity to share safety messages in the absence of an investigation.
On 28 September 2019, the pilot of a Piper PA-25 was conducting glider-tow operations at Benalla Airport, Victoria. After releasing the glider at about 4,000 ft AGL, the pilot began a descent to 1,000 ft. During the descent, the engine failed. The pilot subsequently switched fuel pumps and activated the emergency power system, however experienced no restoration of engine power. He assessed that the aircraft was too low to conduct a glide approach to the runway and elected to land in a paddock near the airport. After the forced landing, he checked the fuel tank and identified that it was empty.
The procedure for refuelling the aircraft was to refuel at the beginning of the day, and again after one hour of towing time. The pilot advised that he took over the aircraft and inspected the log, observing a total of 35 minutes towing time logged. This was consistent with the number of tows completed for the day. The pilot’s expectation was that there was sufficient fuel for another four or five glider tows. He did not visually inspect the fuel tank to confirm the fuel levels during the pre‑flight walk-around and mentioned the fuel gauge indication is difficult to read.
As a result of this occurrence, the aircraft operator has advised the ATSB that they are taking the following safety actions:
The operator sent an email to all glider-tug pilots reminding them of the requirements in regards to fuel checks. Additionally, the fibreglass fuel gauge indicator was polished to allow for easier visual indication so accurate readings can be taken. The operator advised that they are looking into options for replacing the fuel gauge.
This incident serves as a reminder that is in the pilot in command’s responsibility to ensure there is sufficient fuel quantity on board the aircraft.
The Civil Aviation Safety Authority advisory publication, CAAP-234-1 Guidelines for aircraft fuel, provides guidance for fuel quantity crosschecking, specifically that the crosscheck should use at least two different verification methods to determine the quantity of fuel on board the aircraft.
About this report
Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.
- The emergency power system is an independent source of electrical power that supports important electrical systems upon loss of normal power supply. The incident aircraft has a back-up battery fitted that was switched on in this instance, in case the engine stopped due to failure of the primary electrical system.
|Date:||28 September 2019||Investigation status:||Completed|
|Location:||2 km ESE of Benalla Airport|
|Release Date:||08 November 2019||Occurrence category:||Serious Incident|
|Aircraft manufacturer||Piper Aircraft Corp|
|Type of operation||Gliding|
|Damage to aircraft||Nil|
|Departure point||Benalla Airport, Victoria|
|Destination||Benalla Airport, Victoria|