As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TESTS ON CERTAIN LOT NUMBERS, SHOW THAT THE NUTS ATTACHING THE AFT KEEL BEAM AT FS 795.OO TO THE AFT WING SPAR DO NOT AGREE WITH THE SPECIFIED HARDNESS VALUES SPECIFIED. ATTACH HARDWARE AT THE FS 795.00 AFT KEEL FITTING TO REAR WING SPAR WERE REMOVED AND REPLACED, IE SB 670BA-57-025.