What was found
(CAN) ENGINE SPOOL DOWN NOTED TO BE VERY SHORT HIGH RESISTANCE TO TURNING REDUCTION GEAR BOX THROUGH PROP BLADES AND INTERNAL RUBBING DETECTED INDICATING INTERNAL PROBLEMS. - CAUSE TO BE DETERMINED UPON ENGINE TEAR DOWN. - ENGINE WAS INVOLVED IN A PROP STRIKE 10 DAYS (64 FLIGHT HOURS) EARLIER AND HAD JUST BEEN RETURNED TO REGULAR MAINTENANCE INTERVALS AFTER COMPLETING THE REQUIRED INCREASED INSPECTIONS REQUIRED BY THE ENGINE MANUFACTURER. - ENGINE TEAR DOWN SHOULD INDICATE THAT THE PROP STRIKE WAS THE CAUSE.