Narrative:The brand-new Dash-8 passenger plane departed Sault Ste. Marie Airport on an IFR flight plan. The chief pilot, sitting in the left seat, was giving routine recurrent training to the first officer who was flying from the right seat. About 40 minutes after takeoff, the DHC-8 returned to the Sault Ste. Marie Airport to practise instrument approaches. For the final practice approach on runway 11, the crew decided to carry out a flapless ILS approach with a full-stop landing. As the aircraft intercepted the localizer on the inbound leg, the captain simulated a right engine fire. The captain then lowered the gear normally and the approach was continued on the glide slope and localizer with the left engine torque set at 30 per cent and the right engine torque (simulated failed) set at about 16 per cent. Both pitch levers were advanced to produce 1050 rpm. About 150 feet above the ground, the aircraft made an abrupt uncommanded roll to the right and began to lose altitude. The first officer applied full power to the left engine, and the captain, sensing an increasing sink rate, applied power to the right engine as well. However, the aircraft continued to lose altitude rapidly, and it struck the snow-covered ground short of the runway in a 12-degree nose-up attitude, heading 128 degrees in a 24-degree right-wing-low attitude. The right wing tip hit the ground first, followed by the tail of the fuselage, the right main gear, and the right nacelle. The aircraft bounced about 15 feet and then touched down on the still intact left main gear. The nose gear broke off, and the aircraft bounced another 50 feet forward before sliding to a stop. The tail cone, nose gear and right propeller spinner were found along the wreckage trail. All four propeller blades from the right engine separated from the hub during the crash sequence.
Probable Cause:
PROBABLE CAUSE: "The Canadian Aviation Safety Board (CASB) determined that the aircraft was flown in light to moderate icing conditions and accumulated significant airframe icing along the leading edge of the wings and horizontal stabilizer. The crew did not activate the de-icer boots on final approach and allowed the airspeed to decrease to the point where the aircraft departed from controlled flight and struck the ground."
Classification:
Icing
Loss of control
Photos
Map
This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.