What happened
On 2float 26 December 2022, a Glasair Super II FT, registration N600, departed Bankstown, New South Wales, for a flight via Temora to Wedderburn. Following a landing attempt and subsequent go-around on runway 17 at Wedderburn, the aircraft encountered insufficient climb performance. The aircraft was unable to clear surrounding terrain and struck trees approximately 2.7 km southwest of the Wedderburn landing area. The impact resulted in the destruction of the aircraft and two fatalities.
The investigation
The investigation focused on the aircraft's engine, gearbox, and propeller, as well as the pilots' experience and the aircraft's unique systems. While post-accident analysis of the engine and gearbox showed no mechanical discontinuity, fire damage prevented a definitive examination of the electrical and ignition systems. Evidence from witnesses and CCTV suggested the engine was producing high power and the landing attempt was controlled, but the specific reasons for the lack of sufficient climb performance remained undetermined.
Investigators also examined the aircraft's non-standard control layout. In N600, the propeller pitch rocker switches were reversed in their activation orientation between the left and right seats. Additionally, the aircraft lacked a propeller pitch position indicator, increasing pilot reliance on manual settings. The pilots, while experienced in larger multi-engine aircraft, had no prior experience flying this specific amateur-built type.
Findings
- The aircraft's climb performance was inadequate to clear terrain during the go-around.
- The pilots lacked recent experience in single-engine or amateur-built aircraft, which likely hindered their ability to manage the unique handling characteristics and systems of the Glasair Super II FT during an emergency.
- The reversed orientation of the propeller pitch switches between seats increased the risk of inadvertent pitch changes.
- The flight departed Bankstown over populous areas, which was a violation of the special flight permit conditions that prohibit such operations in aircraft using non-certified automotive engines.
- The approach at Wedderburn involved a wide circuit that likely prevented the crew from fully assessing wind conditions, leading to a landing with a quartering left-tailwind in gusty conditions.