As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
L/H HORIZONTAL LOWER SKIN CRACKED AT STA 138, 16 INCHES FROM TRAILING EDGE. GROUNDED - YES. REPAIRED CRACKED SKIN AT STA 138 IAW BOEING 737 SRM 55-10-01-2R-11, THIS IS A CATEGORY B REPAIR WITH A INSPECTION THRESHOLD OF 56,000 CYCLES AND A REPEAT INTERVAL OF 9000 CYCLES.