Accident site
Aircraft Information and Operation Approval
The aircraft was heavily modified, in accordance with a Federal Aviation Administration (FAA) approval, to enable parachuting operations. Since February 2003, the aircraft had been registered in the United States and was being operated seasonally in Canada under the Free Trade Agreement (FTA) with a Canadian Foreign Air Operator Certificate-FTA (CFAOC-FTA). The CFAOCFTA was issued annually by Transport Canada (TC) for parachute jumping operations, recognizing the certificate of authorization issued by the FAA to the operator. At the time of the accident, the parachuting company was using the aircraft for revenue parachute jumping activities.
The aircraft was heavily modified, in accordance with a Federal Aviation Administration (FAA) approval, to enable parachuting operations. Since February 2003, the aircraft had been registered in the United States and was being operated seasonally in Canada under the Free Trade Agreement (FTA) with a Canadian Foreign Air Operator Certificate-FTA (CFAOC-FTA). The CFAOCFTA was issued annually by Transport Canada (TC) for parachute jumping operations, recognizing the certificate of authorization issued by the FAA to the operator. At the time of the accident, the parachuting company was using the aircraft for revenue parachute jumping activities.
Left engine drive splines and coupling
of external spline wear
Close-up of external spline wear
Analysis
It was concluded that mechanical failure of the left-hand engine fuel pump drive splines resulted in the loss of power from that engine. The bang, the shuddering, and the yaw to the right that was experienced may have been caused by the left-hand engine fuel pump drive splines disengaging momentarily and then re-engaging. This disengagement would have caused the engine to flameout, and the re-engagement would have caused a relight with a corresponding bang. This would have been accompanied by a surge of power which could have caused the aircraft to yaw to the right.
A sudden yaw to the right is normally associated with a right-engine power loss. Although the pilot verified the engines’ instruments, he did not correctly identify the left engine as the failed engine. This was likely due in part to the horizontal layout of engine instrumentation that makes timely engine malfunction identification difficult. Moreover, the pilot had not received any training on the King Air for over two years, decreasing his ability to react appropriately. This resulted in the pilot erroneously shutting down the operating engine.
Because the engines were being operated “on condition,” the left engine was operated more than 800 hours past the time before overhaul (TBO) required by the engine manufacturer. Had the 3600-hour overhaul been accomplished, or the phase inspection completed as required in the maintenance instructions, the spline wear and corrosion should have been detected.
The general condition of the aircraft, the condition of the fuel systems, the engine TBO over-run, and the missed inspection items demonstrated inadequate maintenance. The regulatory oversight in place was inadequate because the inspection carried out by the FAA in April 2008 did not identify any of these issues. Furthermore, TC did not carry out any inspections of this operation.
Findings as to causes and contributing factors
1. The general condition of the aircraft, the engine TBO over-run and the missed inspection items demonstrated inadequate maintenance that was not detected by regulatory oversight.
2. The TBO over-run and missed inspections resulted in excessive spline wear in the left engine-driven fuel pump going undetected.
3. The left engine lost power due to mechanical failure of the engine fuel pump drive splines.
4. The horizontal engine instrument arrangement and the lack of recent emergency training made quick engine malfunction identification difficult. This resulted in the pilot shutting down the wrong engine, causing a dualengine power loss and a forced landing.
5. Not using the restraint devices contributed to the seriousness of injuries to some passengers.
Finding as to risk
1. There is a risk to passengers if TC does not verify that holders of CFAOC-FTA meet airworthiness and operational requirements.
Safety action taken
Aircraft Owner
After the accident, the aircraft owner requested that a sister aircraft have its fuel system inspected while undergoing maintenance at an approved maintenance organization in Calgary, Alta. Those inspections revealed numerous heavily corroded components and jelly formed by microbial growth. The fuel drained from the tanks and system was described as milky and was disposed of.
After the accident, the aircraft owner requested that a sister aircraft have its fuel system inspected while undergoing maintenance at an approved maintenance organization in Calgary, Alta. Those inspections revealed numerous heavily corroded components and jelly formed by microbial growth. The fuel drained from the tanks and system was described as milky and was disposed of.
Transport Canada
The Foreign Inspection Division has taken steps to ensure that the regions are notified of foreign air operators that have been issued a CFAOC-FTA for operations in Canada. Procedures will be documented in its staff instruction handbook indicating that the regions are to be notified by e-mail of a CFAOC-FTA operation with the location and dates.
The Foreign Inspection Division has taken steps to ensure that the regions are notified of foreign air operators that have been issued a CFAOC-FTA for operations in Canada. Procedures will be documented in its staff instruction handbook indicating that the regions are to be notified by e-mail of a CFAOC-FTA operation with the location and dates.
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