What was found
(CAN) "SUDDEN YAW, GRINDING NOISE AND CLUTCH WARNING LIGHT IN STRAIGHT AN LEVEL FLIGHT, ALL WITHIN LESS THAN A SECOND. LANDED TO INSPECT THE ACFT, BUT COULDN`T FIND ANYTHING WRONG THAT WOULD HAVE BEEN VISIBLE. CONTINUED FLIGHT AFTER DISCUSSING THE ISSUE WITH AN ENGINEER. THERE WHERE NO FURTHER INDICATIONS OF ANY MALFUNCTIONS DURING THE REST OF THE FLIGHT." MAINTENANCE: AFTER LANDING, THE CLUTCH WAS EXAMINED AND AND FOUND TO MAKE A GRINDING NOISE WHEN TURNED MANUALLY. THE CLUTCH ASSY WAS REPLACED.