Incident Overview
On the evening of an unspecified date, a single-engine Pilatus PC-12/45 aircraft departed Sioux Lookout Airport (CYXL), Ontario, at 1820 local time on an instrument flight rules (IFR) flight to Kasabonika Airport (CYAQ), Ontario. The aircraft carried two pilots and six passengers. The captain served as pilot flying, and the first officer (FO) acted as pilot monitoring.
Flight and Approach
During the approach to Kasabonika, the pilots conducted an area navigation approach to Runway 03 using the autopilot coupled with a GPS. The captain disengaged the autopilot at 1000 feet above ground level, in accordance with the aircraft's pilot operating handbook (POH) limitation. The approach continued at a ground speed of 120 knots with flaps set to 15°.
Landing and Overshoot
The aircraft touched down approximately 1,200 feet beyond the threshold of Runway 03 at a ground speed of 102 knots. During the landing roll, the captain momentarily applied reverse thrust, causing a slight yawing motion. Reverse thrust was returned to idle, and directional control was restored. The captain then fully applied the brakes. At 1938 local time, the aircraft skidded and overshot the end of the runway, coming to rest approximately 350 feet beyond the runway surface. The cabin remained upright and intact, and all occupants egressed through the main cabin door without injury. The aircraft's emergency locator transmitter activated.
Probable Cause
The official investigation cited that the weather conditions present and forecast showed winds becoming westerly, favoring operations on Runway 21. The final approach was conducted at 120 knots ground speed during the last 500 feet, crossing the threshold at 110 knots and touching down at 102 knots. The manufacturer's landing performance specifications in the POH are only provided for dry, paved runways. The normal approach speed for landing with 15° flaps is 98 knots indicated airspeed, but the actual ground speed was 120 knots. Because the approach speed exceeded the POH charts, it was impossible to calculate the required landing distance for the conditions. Additionally, the charts do not account for gravel runways or contaminants such as ice, rain, or snow. Based on calculations using the landing performance charts for a 10-knot tailwind (the maximum charted) without reverse thrust, the aircraft would have required 3,458 feet of available runway.