What was found
AFTER COMPLETION OF A HOIST AT ~0159 AND IN CRUISE FLIGHT BACK TO THE AIRPORT I NOTICED A SLIGHT CHANGE IN THE AIRCRAFT'S NORMAL VIBRATIONS. I SLOWED THE AIRCRAFT TO SEE IF THERE WAS ANY CHANGE IN THE VIBRATION, AND THERE DIDN'T SEEM TO BE. AT THE TIME WE ALSO HAD A SIGNIFICANT TAIL WIND WHICH IN THE PAST HAS BEEN KNOWN TO CAUSE ADDITIONAL VIBRATIONS. I CONTINUED FLIGHT BACK TO THE AIRPORT AND MADE A NORMAL APPROACH TO LANDING. AS WE PASSED THROUGH ETL AND ON SHUTDOWN I COULD FEEL THE AIRCRAFT SURGE LATERALLY CONSISTENT WITH THE FEELING I HAD EXPERIENCED IN OTHER AIRCRAFT THAT HAD BAD LEAD LAG DAMPERS. ON SHUTDOWN THE MOTION BECAME MORE EXAGGERATED AGAIN CONSISTENT WITH A FAILED DAMPER. ON POST FLIGHT IT WAS FOUND THAT THE WHITE BLADES DAMPER WAS SHEARED ON THE OUTBOARD SIDE.