What happened
During an approach to runway 36 at Barwon Heads, the aircraft began descending below its intended flight path approximately half a nautical mile from the runway. Upon noticing the low altitude, the pilot chose to decrease the flap setting by 10° instead of increasing engine power. As the aircraft continued toward the runway, it remained below the required approach profile. The pilot eventually applied power to attempt to regain altitude, but this maneuver failed to prevent the aircraft from striking a truck on Barton Heads Road.
The investigation
Investigators examined the approach geometry and the clearance provided by the displaced threshold. The threshold for runway 36 is situated 78 m from Barwon Heads Road. Based on the 5 per cent approach slope recommended by CAAP 92-1, the height at this distance is 3.9 m above the runway elevation. When accounting for the 0.31 m elevation difference, the resulting clearance is 4.21 m. This clearance is insufficient for road vehicles in Victoria, as the maximum permitted height for such vehicles is 4.6 m.
Findings
- The aircraft descended below the intended approach profile.
- The pilot's decision to reduce flaps rather than add power was an ineffective corrective action for the rate of descent.
- The displaced threshold on runway 36 does not provide the clearance level recommended by CAAP 92-1, creating a risk where a standard approach can intersect with road traffic.