Canada

Findings as to Causes and Contributing Factors:
1. The environmental conditions and loss of visual ground references near Val-d'Or Airport were conducive to spatial disorientation. Because of a lack of instrument flight experience, the pilot probably became disoriented during the overshoot and was unable to regain control of the situation.
2. During the approach, the pilot did not plan to and did not pull up towards the centre of the airport, thereby contributing to spatial disorientation.
3. Although the pilot-in-command received training required by Transport Canada, Aéropro did not ensure that the pilot-in-command completed the required Pilot Proficiency Check (PPC) and was adequately supervised and experienced to conduct a night IFR flight safely as pilot-in-command.

Findings as to Causes and Contributing Factors:
1. For reasons not determined, the pilot did not adhere to the procedures depicted for the LOC DME-B approach to runway 16 at Penticton. As a result, the aircraft did not remain within the confines of protected airspace, was below the minimum safe altitude for the procedure turn, and struck the tower.
Findings as to Risk:
1. The approach was flown in weather conditions that virtually precluded the pilot from completing a landing.
Other Findings:
1. The pilot's flight medical certificate had expired one month prior to the accident, and no information could be found that he had submitted to an FAA medical during that time.

Findings as to Causes and Contributing Factors:
1. A planetary gear disintegrated in the propeller reduction gearbox of the No. 2 engine and caused the engine drive shaft to disconnect from the propeller, resulting in a loss of propulsion from this engine.
2. The planetary gear oil strainer screen wires fractured by fatigue as a consequence of the installation at the last overhaul. This created an unsafe condition and it is most probable that the release of wire fragments and debris from this strainer screen subsequently initiated or contributed to distress of the planetary gear bearing sleeve and resulted in the disintegration of the planetary gear.
3. Although airspeed was above Vmc at the time of the power loss, the aircraft became progressively uncontrollable due to power on the remaining engine not being reduced to relieve the asymmetric thrust condition until impact was imminent.
Findings as to Risk:
1. The propeller reduction gearboxes were inspected in accordance with the West Coast Air maintenance control manual. These inspections exceeded requirements of the de Havilland Equalized Maintenance Maximum Availability program. Since the last inspection, 46 hours of flight time before the accident, did not reveal any anomaly, a risk remains of adverse developments with
resulting consequences occurring during the unmonitored period between inspections.
2. Regulations require the installation of engine oil chip detectors, but not the associated annunciator system on the DHC-6. Without an annunciator system, monitoring of engine oil contamination is limited to the frequency and thoroughness of maintenance inspections. An annunciator system would have provided a method of continuous monitoring and may have warned the crew of the impending problem.
3. Although regulations do not require the aircraft to be equipped with an auto-feather system, its presence may have assisted the flight crew in handling the sudden loss of power by reducing the drag created by a windmilling propeller.
4. Since most air taxi and commuter operators use their own aircraft rather than a simulator for pilot proficiency training, higher-risk emergency scenarios can only be practiced at altitude and discussed in the classroom. As a result, pilots do not gain the benefit of a realistic experience during training.
Other Findings:
1. The fact that the aircraft remained upright and floating in daylight conditions contributed to the successful evacuation of the cabin without injury and enabled about half of the passengers to locate and don their life vests.
2. The aircraft was at low altitude and low airspeed at the time of power loss. The selection of full flaps may have contributed to a single-engine, high-drag situation, making a successful landing difficult.

Findings as to Causes and Contributing Factors:
1. Although the pilot and the aircraft were certified for instrument flight, the pilot apparently continued to fly in accordance with visual flight rules after encountering marginal weather conditions and reduced visibility.
2. For undetermined reasons, the pilot descended below the elevation of the terrain surrounding the airstrip, resulting in a controlled-flight-into-terrain accident.
Finding as to Risk:
1. Given the pilot's flying time during the 30 days before the accident, the pilot=s performance might have been affected by fatigue.

Findings as to Causes and Contributing Factors:
1. The steering control valve lever was not reassembled in accordance with the specifications and the drawings in the overhaul manual and the maintenance manual: the lever was assembled with two washers instead of one, and the circumference of the bushing was 0.0005 inch greater than the circumference of the hole in the lever. These two deficiencies created additional resistance that
impeded the pivoting of the aircraft steering wheel.
2. The nylon locknuts were reinstalled during the repair of the steering control valve, contrary to the recommendation that they be used only once. The locknuts then came loose in service, creating play in the parts of the valve.
3. Incorrect interpretation of the problem and the influence of previous experience using the nose-gear steering wheel led the crew to make the flight despite their concern about the aircraft's nose-gear steering system.
Findings as to Risk:
1. The maintenance personnel of Precision Aero Components Inc. used the (incomplete) maintenance manual instead of the overhaul manual to overhaul and repair the steering control valve,
contributing to the incorrect reassembly of the valve.
2. The steering control valve lever was not fitted with a grease fitting, and the outside of the bushing was not grooved to allow adequate lubrication, thereby risking corrosion and seizure of the bushing inside the lever.
3. The limited experience and the lack of formal training of the maintenance personnel concerning the repair and the overhaul on the steering control valve might have contributed to the incorrect
reassembly of the steering control valve.
4. The pilot flying cut the electrical power, as required by the hard landing procedure. The left engine could therefore not be shut down, causing a risk of injury when the passengers evacuated.
5. The pilot flying cut the electrical power after the aircraft exited the runway, as required by the hard landing procedure. The electrical power required to operate the public address and alarm systems was thereby lost, and the evacuation could not be ordered promptly.
6. The evacuation slide automatic deployment system was inadvertently deactivated, which could have delayed the evacuation and compromised passenger safety.
7. After separating from the engine, the left propeller blades entered the fuselage and damaged an unoccupied seat.
Other Findings:
1. The numerous changes in ownership of the Convair type certificate and the lack of technical support from the current holder caused maintenance problems for Convair operators and approved
maintenance organizations (AMOs), particularly for recently established AMOs.

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. The pilot's decision to depart from the unlit location was likely the result of the many psychological and physiological stressors encountered during the day.
2. The pilot most likely experienced spatial disorientation-precipitated by local geographic and environmental conditions-and lost control of the aircraft.
Findings as to Risk:
1. Without a safety management program that routinely disseminates safety information, RCMP pilots may be inadequately sensitized to the limitations of decision making and judgement.
2. The RCMP had no current, concise standard operating procedures (SOPs) for its non-604 operations. Without useable SOPs, the pilots in some instances operate without clearly established limits and outside of acceptable tolerances.