Accident Overview
Flight 106 was a scheduled service from Vancouver to Powell River with an intermediate stop at Sechelt. The flight to Sechelt was uneventful. While approaching Porpoise Bay at Sechelt, at an altitude of 200 feet, the twin-engine airplane rolled to the right to an angle of 90°, then nosed down and crashed on the east shore of the bay, about 50 meters from the water.
Casualties and Injuries
The captain and a passenger were killed. Fourteen other occupants sustained injuries, four of them seriously.
Investigation Findings
The following findings were identified in the official investigation. Under normal flight loads, the right-hand aileron control rod of the aircraft, specifically the bellcrank to aileron push-pull rod, separated from the bellcrank end fitting due to an extensive stress corrosion crack. The failure allowed the right aileron to float to an UP position, causing an asymmetric lift condition and consequent loss of control.
The aircraft was on final approach at an altitude of about 200 feet when it began a roll to the right. Under the circumstances, this roll was uncontrollable; the aircraft descended and struck the ground with the right wing down at an angle of 45° ±5°.
The specific visual inspection of aileron control rods was found to be inadequate to detect stress corrosion cracking. Previous stress corrosion failures of flap control rods on aircraft of this type had led to corrective airworthiness action by the Department of Transport and the manufacturer. However, these measures had not been applied to the aileron rods, which are of similar construction.