As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FOUND CASE CRACKED BEYOND REPAIR AT NR 1 CYLINDER, FOUND 2 THRU BOLTS SHEARED AND 5 CYLINDER STUDS BROKEN ON NR 1 CYLINDER. THRU BOLTS DEFECTIVE CAUSING A CHAIN REACTION IN SHEARING CYLINDER STUDS. SINCE CYLINDER WAS NO LONGER SEATED SQUARELY TO THE CASE, THIS CAUSED THE CASE TO CRACK WHILE ENGINE WAS IN OPERATION. (K)