What happened
On a flight from Kakabikitchiwan Lake, Ontario, to Aremis Lake, a de Havilland DHC-2 seaplane, registration C-FNFO, was flying at an unusually low altitude over Sabaskong Bay. Although the pilot typically cruised between 1,000 and 2,000 feet, the aircraft was observed flying approximately 20 feet above the water at a high power setting. During a left turn and climb, the right wing of the aircraft struck a low-hanging electrical wire spanning a channel between two islands. The impact caused the aircraft to disintegrate, leaving the wreckage scattered across the channel. The pilot sustained fatal injuries.
The investigation
Investigators examined the wreckage and found no evidence of mechanical failure or airframe defects prior to the impact. The damage to the de HavSB DHC-2 was consistent with the extreme forces of hitting the wire and the subsequent water impact. The investigation focused on the visibility of the wires and the regulatory oversight of the obstruction.
It was determined that the power lines were not marked for aviation safety. The supporting poles were obscured by trees, making the wires nearly invisible until the aircraft was at very close range. While the Canada Water Aerodrome Supplement included warnings about numerous power lines in the area, no specific aeronautical evaluation had been conducted by Transport Canada to mandate marking for this particular wire. Furthermore, the utility company's practices for overhead versus underwater lines were based on economic and technical factors rather than a standardized safety mandate.
Findings
- The overhead power line was not marked and remained invisible to the pilot until it was too late to avoid.
- The pilot was flying at an extremely low altitude, which likely prevented the detection of the unmarked wires.
- Regulatory discretion allowed the obstruction to remain unassessed and unmarked.