What happened
A West Caribou Air Service Inc. Cessna 185A, registration C-FBWP, was conducting a visual flight rules flight from Summer Beaver to Thunder Bay, Ontario, when the engine lost power. The aircraft, carrying one pilot and one passenger, was performing a gradual right turn to avoid entering controlled airspace without clearance when the power loss occurred. The pilot attempted to level the wings and perform emergency checks, but the engine failed to restart. The aircraft subsequently struck trees approximately 10 nautical miles northeast of Thunder Bay. While the aircraft sustained substantial damage, both occupants escaped the wreckage without injury.
The investigation
The investigation focused on several critical areas, including the aircraft's fuel system, the pilot's training, and the pre-flight planning. Investigators examined the fuel tanks and found that the right tank was empty, while the left tank contained a small amount of remaining fuel. The engine-driven fuel pump was found to be non-self-priming, meaning it required boost pressure to function.
Regarding training, investigators could not verify if the pilot's company-specific training met all regulatory or manual requirements due to incomplete and inconsistent logbook entries. Furthermore, the investigation looked into the fueling process, noting that the pilot used the inboard filler openings, which resulted in a lower fuel volume than the intended full load. The investigation also reviewed the pilot's pre-flight calculations, which had underestimated the actual flight duration and overestimated the aircraft's endurance.
Findings
- The pilot's pre-flight planning was inaccurate, as he underestimated the en route time and overestimated the aircraft's fuel endurance.
- A lack of clear communication between the acting chief pilot and the pilot regarding "full fuel" led to the aircraft departing with a reduced fuel load.
- The pilot did not monitor fuel levels during the flight because the aircraft's fuel gauges were known to be unreliable.
- Fuel starvation occurred when the remaining fuel in the left tank moved away from the supply pickups during a right turn.
- The pilot failed to activate the electric auxiliary fuel pump following the engine power loss, preventing the restoration of engine power.
- The baggage in the cabin was not properly secured, which increased the risk of injury during the impact.