Runway undershoot involving a Pilatus PC-12/47, VH-HIG, at Coober Pedy Airport, South Australia, on 23 September 2014

On 23 September 2014, a Pilatus PC-12 aircraft, registered VH-HIG, was arriving at Coober Pedy, South Australia after a flight from Amata, South Australia. The pilot and one passenger were on board the aircraft. Approaching Coober Pedy, the pilot observed a line of storm activity, virga and blowing dust in the vicinity of the aerodrome.

The pilot positioned for a landing on runway 32, but discontinued the first landing attempt after losing visual contact with the runway due to blowing dust. As the aircraft descended through about 100 ft above ground level during the second landing attempt, the pilot encountered strong wind shear and the aircraft sink rate increased significantly. Almost simultaneously, the aircraft was engulfed in blowing dust which denied the pilot external visual reference. The pilot contemplated another go-around, but noting the very high sink rate, the intensity of the turbulence and the proximity of the aircraft to the ground, he assessed that he could not execute a go-around safely.

The aircraft touched down short of the runway threshold and to the right of the runway centreline, on a firm surface that was once part of the runway strip. The aircraft passed through a wire aerodrome perimeter fence, and came to a stop after a ground roll of around 150 m. The pilot was unable to see outside the aircraft until it had almost come to a stop, and apart from buffeting and intense wind noise, he did not feel anything unusual during the ground roll. The pilot taxied to the terminal area to refuel the aircraft, unaware at that point that the aircraft had passed through the perimeter fence during the landing roll.

After refuelling, the flight continued to Adelaide where an engineering inspection revealed damage in the area where the nose landing gear meets the aircraft structure, and scoring damage to the underside of the left wing and flap.

Virga extending from convective cloud, blowing dust and dust devils are visual indications that may provide a warning of hazardous wind shear in the area. Pilots are encouraged to monitor the environment for any signs of hazardous weather, and remain particularly mindful of the significant dangers associated with wind shear.

Aviation Short Investigations Bulletin - Issue 39