De Havilland DHC-2 Beaver

Findings as to Causes and Contributing Factors:
1. The power line running overhead the channel was invisible, except at very short range, and was not marked to indicate its presence.
2. The pilot was flying at a very low altitude and likely did not see the power line.
Findings as to Risk:
1. The Standards Obstruction Markings Manual allows for discretion in deciding whether to assess obstructions, making it possible for some obstructions to not be assessed and, consequently, to not be marked.

Findings as to Causes and Contributing Factors:
1. The pilot did not avoid the trees that obstructed his immediate flight path on descent to the lake.
2. The damage to the aircraft from the tree-strike seriously compromised the pilot's ability to control the aircraft, to the point where continued flight was impossible.
3. The pilot and the passenger suffered serious injuries. It is highly likely that proper use of a passenger restraint system would have lessened the injuries to both persons.
Findings as to Risk:
1. Canadian regulations regarding the use of seats and seat restraint systems are not sufficiently clear about high-risk, aerial work operations, such as aerial application.
2. Transport Canada was not advised of the fish-dropping operations and was unaware that the passenger in the cabin was unrestrained during high-risk operations.
3. Canadian regulations do not require specific training in aerial application techniques, such as fish-dropping.
4. The installation of the fish-hopper equipment constituted an aircraft modification, which had not been approved by Transport Canada.
Other Findings:
1. The operator did not maintain a proper logbook.

Findings as to Causes and Contributing Factors:
1. When the pilot entered a turn, the combined effects of the increased g-forces, power reduction, the aircraft=s heavy weight, the aft CofG, retraction of the flaps, and the wind conditions resulted in
the aircraft stalling. The aircraft struck the lake surface before the pilot was able to re-establish a level-flight attitude.
2. The aircraft was operating in excess of 385 pounds above the maximum gross takeoff weight, and the CofG was about 2.7 inches aft of the aft limit. This loading configuration aggravated the stall characteristics of the aircraft.
3. The pilot reduced power and raised the flaps before the climb was complete, contrary to the Pilot Operating Handbook, thereby increasing the aircraft's stall speed.
Other Findings:
1. The shoulder harnesses worn by the pilot and the front passenger likely prevented serious head injuries.
2. The centre seat broke from its footings. This may have incapacitated the two passengers inside the aircraft or impeded their escape.

Findings as to Causes and Contributing Factors:
1. The aircraft probably stalled with insufficient altitude for the pilot to execute a recovery.
2. The prevailing conditions were conducive to optical illusions associated with low-altitude flight over rising terrain.
3. The aircraft was not equipped with a stall warning system, nor was it required by regulation.
4. The pilot's decision to fly at low altitude and probably use cutback power for the climb did not allow for safe obstacle clearance.
5. The pre-flight safety briefing did not inform passengers where to find the survival equipment on board the aircraft. Consequently, they could not use the sleeping bags to protect themselves from exposure and thereby delay hypothermia.
6. Rescue was late because the mostly white aircraft blended into the snowy ground, making it difficult to locate, and the ELT antenna was broken, reducing the range of the signal. Consequently, the survivors' exposure time was increased.
Other Findings:
1. The pilot was certified and qualified for the flight.
2. The autopsy and toxicological test results revealed no indication that physiological factors affected the pilot's performance.
3. Records indicate that the aircraft was certified, equipped, and maintained in accordance with existing regulations and approved procedures.
4. The aircraft's weight and centre of gravity were within the limits specified in the aircraft fight manual.
5. There is no indication that there was an emergency situation or that the aircraft experienced problems prior to impact.
6. The ready-to-use weight and balance calculation form is not consistent with the standard. Transport Canada reported this irregularity in 1992, but no change was made in the form, which is still part of the company operations manual approved by Transport Canada on 23 October 1999.
7. The weather conditions were suitable for visual flight.

The pilot's failure to ensure attainment of adequate airspeed prior to initiating a steep turn at low altitude, resulting in an accelerated stall. A factor contributing to the occurrence of the accident was the aircraft's low altitude. Factors contributing to the severity of the accident included a water impact, and jammed/restricted doors due to impact damage resulting in degraded aircraft evacuation capability.

Findings as to Causes and Contributing Factors:
- The engine quit operating because the aircraft fuel system was contaminated with a large amount of water.
- The most likely source of the water contamination was the drums from which the aircraft was refuelled.
- A proper filter to prevent water contamination was not used when the aircraft was refuelled.
- The nose-level aircraft attitude when beached and the freezing of water probably prevented the water contamination from being drained from the front tank during the pilot's pre-flight checks.
Other Findings:
- The aircraft's maintenance records indicate that the aircraft was certified, equipped, and maintained in accordance with existing regulations and approved procedures.
- The use of the available shoulder harnesses probably prevented serious injury to the pilot and engineer.