On 18 May 2014, the pilot of a Piper PA-25, registered VH-SSO, took off from Bacchus Marsh aeroplane landing area (ALA) with a glider in tow. During climb the pilot noticed a momentary engine power loss, following which the glider pilot released the tow rope. The pilot of the PA-25 immediately re-joined the circuit via the downwind leg. The engine responded normally to throttle inputs following the momentary power loss, but after the pilot turned onto the base leg of the circuit, the engine surged briefly then stopped. The pilot conducted a forced landing but the aircraft landed heavily and was substantially damaged. The pilot was uninjured. Subsequent inspection found that the aircraft fuel supply was exhausted.

The gliding club that operated the PA-25 used aircraft flight time to determine when a refuel was required. According to this system of fuel management, a refuel was required at 1284.1 hours flight time, but the flight time following the accident was almost 1284.9 hours. The pilot was familiar with this system, but it was ineffective in alerting the pilot of the need to refuel on this occasion. The aircraft was fitted with a warning light to alert pilots to a low fuel level condition, but the light did not illuminate during flight on this occasion.

The pilot was not expecting to fly on the day of the accident and did not follow his usual pre-flight routine, which normally included a physical check of the aircraft fuel state. The pilot may have been suffering from an elevated level of fatigue having had very little sleep during the evening prior to the accident.

In response to this accident, the Gliding Federation of Australia planned to remind all glider towing pilots of the importance of fuel management and fatigue awareness. This accident highlights the importance of careful attention to the fuel state of an aircraft, and the need for caution when usual pre-flight preparation is interrupted or abnormal. This accident also serves to remind pilots to carefully consider the possible effects of fatigue before engaging in flying operations.


Aviation Short Investigation Bulletin - Issue 35