Kind of looks like the input module freewheeling unit locked up and the engine torque sheared the flange maybe?
That would have been hectic, here’s the scenario they maybe faced in my opinion.
First an abrupt drop of NR, so maybe you would initially think EDECU Low side failure, but then the engine high speed shaft fails due to the input module freewheeling unit binding/locking up. This would probably have happened quick, that may be the “Pop” that was mentioned by someone else in the thread.
Now the shaft is flailing around under the gimbal seal at high rpm (20,900rpm) making a hell of a racket, engine EDECU overspeed protection would be active, shutting of fuel flow repeatedly to prevent overspeed until they could retard the PCL to idle so engine indications on that engine would be all over the place.
It’s obvious they landed single engine, kept their cool and prevented as much as possible further damage to the aircraft and injury to the crew and people on the ground. Excellent, maybe Broken Wing award worthy?
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