A steel spring that disintegrated in the engine led to the emergency landing of a smoke-filled airplane in Nanaimo this past winter.
The Transportation Safety Board of Canada released its report today about the incident, which happened on a WestJet Encore flight to Nanaimo Airport on March 20. While en route from Vancouver, crew and passengers noticed smoke in the cockpit and cabin and an emergency was declared with Air Traffic Services.
The Bombardier DHC-8-402 was powered by two Pratt and Whitney Canada PW150A turboprop engines and after the incident, the engine was shipped to the manufacturer in Montreal for teardown and inspection, according to the TSB report.
A wave washer was found disintegrated, “compromising the efficiency of the carbon seal,” noted the report. “That deficiency had in turn allowed turbine oil to leak past the carbon seal and enter the compressor airstream and the cabin pressurization system.”
A safety bulletin had called for modification of the carbon seal, but under a Category 6 urgency, meaning compliance was recommended to take place during engine overhaul and disassembly.
“The occurrence engine was not due for overhaul and had not been disassembled for repair; therefore, the recommendation in the [safety bulletin] was not performed,” the report noted.
Transportation Safety Board of Canada released its report on a plane that filled with smoke and had to make an emergency landing in Nanaimo in March. A steel spring in the engine's carbon seal disintegrated… https://t.co/9rjoeK32jr #Nanaimo pic.twitter.com/Sd95FA6Qoq
— Nanaimo Bulletin (@NanaimoBulletin) July 13, 2018
The engine manufacturer P&WC has “developed a new oil analysis technology” to mitigate risk, and WestJet has implemented the technology across its Q400 fleet.
“The aircraft crew responded appropriately and rapidly during the occurrence and were able to land and evacuate the aircraft with no injuries and no damage,” the report summarizes. “Air Traffic Services and airport personnel also responded in a timely manner, which contributed to the positive outcome.”