As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCN - C21 CK - "C" - WHILE INVESTIGATING POSSIBLE CORROSION AROUND FASTENERS AT BS 727 + 17, STR 27L TO 27R, FOUND A 3" CRACK IN STR 27R. NOTE; NO CORROSION WAS FOUND. MAINTENANCE REMOVED CRACKED SECTION OF STR 27R AND INSTALLED REPAIR IAW B737 SRM 53-10-6.