What aircraft was involved and where did it happen?

The accident on 1997-08-10 involved a Aux Mélèzes River, Quebec, operated by Cessna 180K C-GIGK, at CA.

What was the probable cause of the accident?

The exact cause of the accident could not be determined, but investigators identified that an unexplained distraction or optical illusions may have contributed to the pilot's failure to maintain separation from the rising terrain.

Fatal crash of Cessna 180K in northern Quebec valley

A two-seat seaplane crashed into rising terrain in the aux Mélèzes River region, resulting in two fatalities and the destruction of the aircraft by fire.

What happened

On 10 August 1997, two Cessna 180K seaplanes, registered as C-GIGK and CF-RHI, departed from Lake Maricourt, Quebec, for a fishing expedition in the Ungava Bay region. After an initial landing on the du Gué River, the aircraft C-GIGK, carrying a pilot and one passenger, departed toward the aux Mélèzes River to locate a suitable campsite.

During an approach to the river, the pilot initiated a go-around due to concerns regarding the suitability of the water landing area. While performing a low-level reconnaissance circuit, the aircraft struck the south slope of a valley. The impact caused a fuel leak from the right wing, which ignited shortly after contact. The pilot and passenger, both of whom sustained fatal injuries, were unable to evacuate the cabin before the fire consumed the aircraft.

The investigation

Investigators examined the wreckage of C-GIGK and found no evidence of mechanical failure, engine malfunction, or flight control deficiencies. The aircraft's weight and balance were within legal limits, and maintenance records were found to be in compliance with regulations. The pilot was fully qualified for the operation, and toxicology reports showed no evidence of impairment.

Weather conditions were suitable for visual flight, though a 20-knot wind was present. The investigation focused on the pilot's flight path during the circuit, noting that the aircraft was flying at a low altitude and low speed to survey the water. While the pilot attempted to maneuver away from the ridge following a warning from the pilot of CF-RHI, the proximity to the rising terrain left very little margin for error.

Findings

The pilot's decision to perform a go-around was a justified safety maneuver.
The aircraft's flight path did not utilize the full available space within the valley, which limited the ability to manage the aircraft's roll and performance during turns.
An unexplained distraction or the presence of optical illusions may have prevented the pilot from recognizing the encroaching terrain until it was too late.
The post-crash fire, likely ignited by an electrical source or engine heat, occurred so rapidly that evacuation was impossible.

Safety action

To improve pilot awareness of the dangers posed by flying over rising terrain at low altitudes, Transport Canada planned to publish an educational article regarding the risks of optical illusions in its Aviation Safety Letter.