As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE AIRCRAFT MADE AN EMERGENCY LANDING WITH THE RIGHT ENGINE FEATHERED. THE COPILOT HAD NOTED NR 4 CYLINDER EXIT THROUGH THE SIDE COWLING IN A DOWNWARD DIRECTION. THE CONNECTING ROD WAS STILL ON THE CRANK, BENT SLIGHTLY AFT AND THE PISTON PIN BOSS WAS ELONGATED. ALL HOLD-DOWNS WERE BROKEN OFF.