What was found
(CAN) DURING AN APPROACH FOR LANDING TO REFUEL, THE PILOT AND ENGINEER ON BOARD EXPERIENCED A NOTICEABLE VIBRATION. UPON LANDING THE ENGINEER FOUND THAT A M/R BLADE PIN WAS SITTING A BIT HIGHER THAN THE OTHERS. WHEN HE UNLATCHED TO PIN, THE THREADED PORTION OF THE PIN DROPPED OUT, INDICATING THAT IT HAD BROKEN NEAR THE SHANK AND TOP OF THE THREADED REGION. THE AIRCRAFT WAS GROUNDED, NEW PIN ORDERED, AND ALL OF THE REMAINING M/RBLADES PINS WERE INSPECTED..