As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR CONDITIONING DRIVE PULLEY SUPPORT BEARING ON FORWARD END FAILED AND CAUSED THE QUILL SHAFT TO SHEAR. SUBMITTER STATED THIS IS THE FOURTH SUCH FAILURE IN 1,390 HOURS OF AIRCRAFT OPERATION. BEECHCRAFT RECOMMENDS THE QUILL SHAFT BE LUBED AT 600 HOURS AND THE BEARINGS BE INSPECTED.