As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CRACKS FOUND IN CARRY THRU ASSEMBLY AT LOW POINT OF MILLED CUT OUTS IN UPPER TUBE OF ASSEMBLY. THE MILLING PROCESS LEFT A SHARP EDGE CREATING A STRESS RISER. THIS WAS A FACTOR CONTRIBUTING TO CRACKS DEVELOPING. WE HAVE DRESSED OUR OTHER CARRY THRU ASSEMBLIES TO A 1/8" RADIUS POLISHED BULL NOSE PROFILE.