What happened
On May 1, 1995, two aircraft collided at 4,500 feet above sea level, approximately 12 nautical miles northwest of Sioux Lookout, Ontario. The first aircraft, an Air Sandy Piper PA-31 Navajo (C-GYPZ), had departed Sioux Lookout for Red Lake under visual flight rules (VFR) with one pilot and four passengers. Simultaneously, a Bearskin Airlines Fairchild Swearingen Metro 23 (C-GYYB) was flying an instrument flight rules (IFR) route from Red Lake to Sioux Lookout, carrying two crew members and one passenger.
At approximately 13:28, a mid-air impact occurred between the two aircraft. The collision was witnessed by another pilot in the area, who reported seeing a bright flare and a subsequent fire in a wooded area. Search and rescue efforts confirmed that the Air Sandy aircraft had crashed into a wooded area, while the Bearskin aircraft had struck Lac Seul. The collision resulted in eight fatalities.
The investigation
The investigation examined the flight paths, the use of navigation technology, and the effectiveness of traffic separation. Investigators looked into the role of the Sioux Lookout Flight Service Station (FSS) and the impact of GPS usage on aircraft separation. The investigation also reviewed the physiological limitations of the pilots regarding the see-and-avoid concept and the maintenance records of both aircraft.
Findings
- The pilots of both aircraft failed to visually detect one another in time to perform evasive maneuvers.
- The estimated closing speed of the two aircraft was 410 knots, a rate that significantly reduces the probability of successful visual acquisition.
- Neither crew was alerted to the other's presence by onboard electronic equipment or by the Flight Service specialist.
- The use of GPS technology had reduced lateral displacement between aircraft on similar tracks, increasing the risk of collision when following the same airways.
- There was an apparent lack of pilot understanding regarding how to optimize avoidance maneuvers, as the Navajo was noted to be in a steep bank at the time of impact.
Safety action
- The TSB recommended that the Department of Transport expedite the development of safe separation procedures for aircraft using GPS.
- A recommendation was made to ensure aircraft fly at reduced speeds near aerodromes when relying on the see-and-avoid method.
- The Board suggested that Transport Canada take steps to improve pilots' ability to recognize collision geometry and optimize avoidance maneuvers.
- The TSB recommended an analysis of the benefits of requiring commercial passenger-carrying aircraft to be equipped with TCAS.