Aircraft and Crew
The accident aircraft was a Piper PA-18, registration C-FJYS (serial number 18-4734), operated by B. Allison Flying Services under Canadian Aviation Regulation (CAR) 703 Air Taxi Operations. The pilot held a valid commercial licence and had logged 1043 total flight hours, mostly in single-engine aircraft, as of 03 June 2005. The aircraft was certified, equipped, and maintained in accordance with regulations, with no known deficiencies before the first flight of the day. Weight and centre of gravity were within approved limits.
Accident Sequence
The pilot departed Cooking Lake Airport, Alberta, at approximately 1130 mountain daylight time (MDT) and landed at Chipman airfield, where a passenger boarded. They departed at 1212 for the last day of two weeks of aerial photography. Weather at departure was clear with nearly calm winds. Based on the departure time, Hobbs meter reading, and sun shadows in passenger photographs, the accident occurred at approximately 1230. The aircraft wreckage was found by a farmer at about 1810 in a hay field 9 nautical miles west of Andrew, Alberta. The aircraft struck the ground at an extreme nose-down, left-wing-low attitude and was substantially damaged. There was no post-impact fire.
Wreckage and Investigation
Examination of the wreckage revealed that the pilot was wearing a full four-point harness; the passenger had a lap-belt but the shoulder harnesses were not buckled. The rear control stick had been removed, and no stub cover was found. The rear-seat rudder pedals were operable. All flight controls were continuous. One propeller blade sliced into the ground at a 70° angle, tip bent forward, indicating the engine was generating power. The other blade was bent backward. Engine examination showed no abnormalities; instruments indicated nearly full power at impact, with two marks on the airspeed indicator at 0 and 79 knots. The left fuel tank contained no fuel, and the belly tank (STC #SA02068AK) had broken open and was empty. The right tank was estimated three-quarters full. Fuel lines from the right tank contained fuel; the line from the gascolator to the carburetor was destroyed. The fuel selector was set on the left tank, but might have moved at impact. A company fuel log entry of 25 US gallons on 06 July was unsigned and likely made by the pilot.
No emergency locator transmitter (ELT) signal was received; the ELT was armed but the antenna coaxial cable was pulled out at impact. The cable had been installed tightly with no allowance for fuselage deformation. A portable GPS unit was damaged and provided no data. The aircraft was not equipped with a flight data recorder or cockpit voice recorder, and neither was required.
Findings
The Transportation Safety Board (TSB) determined the probable cause: "For undetermined reasons, the aircraft departed controlled flight and struck the ground." The tight installation of the ELT antenna cable resulted in disconnection at impact, preventing an effective signal. The pilot did not file a flight plan or company flight itinerary, delaying possible rescue. Procedures for delegation of management authority in the absence of key personnel were incomplete, leading to ineffective flight following and emergency response. Investigators could not determine why the aircraft departed controlled flight; a recording device might have helped.
Safety Action
Following the accident, the company implemented a delegation system to ensure management authority is always present, drafted checklists for management positions, and strengthened flight following by requiring pilots to submit a comprehensive flight itinerary or flight plan. The telephone answering service is no longer used as the primary flight following system. Acting managers assume responsibility using a delegated duties checklist, and overdue alerting is more rigidly followed.