What happened
On the afternoon of the accident, a de Havilland DHC-2 Beaver floatplane, registered C-GVHT, departed Campbell River, British Columbia, for a flight to a logging camp at Mackenzie Sound. The aircraft, operated by Wahkash Contracting Ltd., was carrying a pilot and four passengers. After a brief stop at Hoeya in Knight Inlet to offload food, the aircraft continued toward its destination.
Upon arriving over the Mackenzie camp, the pilot radioed ground personnel to report that the aircraft was flying at 2,800 feet between cloud layers, with no available descent path due to weather. The pilot intended to assess the weather through a pass at the end of the Frederic Creek valley. During a second attempt to navigate the pass, the pilot performed a sharp left turn to avoid rising terrain. During this maneuver, the aircraft entered a steep, nose-down flight path, striking trees and coming to rest inverted. All five occupants were fatally injured, and the aircraft was destroyed.
The investigation
Investigators examined the wreckage and the flight path, noting that the aircraft's impact with trees was consistent with a sudden loss of control. The investigation focused on operational factors, as no mechanical failures were identified.
Technical analysis revealed that the aircraft was operating outside its certified flight envelope. The total weight exceeded the maximum allowable utility weight, and the center of gravity (CG) was positioned beyond the approved aft limit for floatplane operations. Furthermore, errors in the aircraft's recorded basic weight and passenger weight estimates meant that any weight and balance calculations performed by the pilot would have been approximately 450 pounds lighter than the actual load.
Findings
- The pilot attempted to maneuver the aircraft through a confined area of the valley to avoid clouds, which necessitated an aggressive turn.
- The aircraft stalled during a steep, high-bank turn at low speed.
- The aircraft was overloaded and the CG was outside the aft limit, which made the stall more likely and the subsequent recovery nearly impossible.
- Inaccurate weight and balance documentation prevented the pilot from identifying that the aircraft was over its maximum weight.
- The installation of an Alaska cargo door increased cargo volume, which contributed to the possibility of heavier loads being placed too far aft.
- Unsecured cargo may have shifted during the maneuver, further destabilizing the aircraft's balance.