The Transportation Safety Board of Canada (TSB) on Tuesday released its investigation report into a May 2024 engine failure that forced a Pilatus PC-12/47 to land on sea ice near Rankin Inlet, Nunavut. The flight, which included two crew members and one passenger, did not result in any injuries.
Routine Flight Turns Into Emergency
The flight was part of a multi-day series of legs operated by Quebec-based Kudlik Aviation. The PC-12 had performed normally earlier that morning on flights from Taloyoak and Naujaat. The pilots—an experienced captain with more than 15,000 flight hours, around 14,200 of which were in the PC-12/47. The first officer had 712, with just over 500 hours in the PC-12/47.
The PC-12 itself was built in 2006 and had 13,747.8 hours of total time since it was built. According to the report, the aircraft was in compliance with all required maintenance, ADs, and applicable service bulletins.
The report said the aircraft was descending toward Rankin Inlet Airport on May 7 when the engine emitted a series of bangs and flames appeared from the exhaust ducts. Power dropped sharply moments later.
The crew declared an emergency after attempting to remedy the power drop and aimed for what they deemed the safest available surface—a patch of sea ice roughly five nautical miles east of the airport.
The PC-12 touched down with its landing gear retracted at 9:51 a.m. local time. The emergency locator transmitter did not activate automatically, but the crew manually triggered it, and the signal was relayed to the Joint Rescue Coordination Centre in Trenton, Ontario.
Local Royal Canadian Mounted Police officers and firefighters reached the aircraft by snowmobile about 80 minutes after the landing. All occupants were wearing safety belts and shoulder harnesses, and they exited the airplane without injury.
The wheels-up, off-field landing did not result in any fire or accompanying fuel or oil leakage.
Turbine Blade Failure
The engine— a Pratt & Whitney Canada PT6A-67B with 4,558.4 hours and 2417 cycles since the last overhaul—remained largely intact after the landing, but investigators found extensive damage in both power turbine stages. Blades in the two stages experienced midspan fractures, the agency said, with most fragments exiting through the exhaust ducts. The compressor and combustion sections showed no abnormalities.
A metallurgical examination found that the blades met manufacturing material specifications and showed no evidence of fatigue or degradation. Instead, the fractures were consistent with tensile overload. The report stated the cause of the blade failure could not be determined.
Investigators also noted galling and overheating signatures on bearing surfaces in the propeller reduction gearbox, though the source of that damage was also not identified. Oil samples taken from the gearbox were discolored and contained particles rich in lead and copper.
Data pulled from the PC-12’s engine condition monitoring system showed the engine was operating within recommended power settings before the failure, and no link was found between an unusual “bang” noise pilots heard on a different flight the previous day and the power loss near Rankin Inlet.
The engine performed within normal parameters when later tested in a ground run coordinated with a maintenance provider, and according to the report, investigators were unable to reproduce the noises described by the crew that preceded the aircraft’s drop in power.
While the report did not manage to find much conclusive root-cause information, the agency did make it a point to emphasize the role that the correct use of safety belts and cargo restraints played in the survivability of the accident.
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