As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACFT IN IN FOR A C-CHECK WHEN CORROSION WAS FOUND IN THE LT SILL AT SCREW HOLES AT FRAMES 19 AND 20. MX REMOVED THE DAMAGED PART, DRILLED AND INSTALL A NEW SILL RE SRM 51-40-02 AND 51-40-03. ALL WORK ACCOMPLISHED AND WILL BE RELEASED AT THE END OF THE CHECK.