As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ANNUAL INSPECTION, NOTICED BULGING UNDER RIGHT REAR SPAR FUSELAGE ATTACH PLATE. SEVERAL RIVETS ALSO HAD HEADS MISSING. REMOVED STEEL PLATE FROM SPAR, FOUND SEVERE CORROSION OF SPAR. INSTALLED NEW SPAR. CLOSE INSPECTION OF THESE OLDER AIRPLANES NEEDS TO BE GIVEN PARTICULARLY WHERE STEEL AND ALUMINUM ARE RIVETED TOGETHER.