C-FSGN, a Diamond DA 42 aircraft operated by Chinook Helicopters, was on a local training flight in the vicinity of Abbotsford, BC (CYXX) with 2 persons on board. During the flight, the left engine (Thielert TAE 125-01 Centurion 1.7L) and propeller (MT Propeller MTV-6-A-C-F/CF187-129) began making an unusual noise.
Shortly thereafter, smoke was observed coming from the rear of the left engine. The pilot shut the engine down and declared an emergency. The aircraft landed on Runway 25 at CYXX without further incident, with ARFF standing by. There were no reported injuries. The operator’s maintenance removed the Engine Gearbox Assembly (P/N 02-7210-07944R2) and discovered that the rear seal had been leaking oil onto the clutch assembly (P/N 05-7211- K009406-AT).
The clutch plate assembly was found to be blue and blistered from overheating.