As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A SERVICE CHECK WALK AROUND, A PUNCTURE WITH INSULATION MATERIAL EXPOSED WAS FOUND BELOW THE CAPTAIN DV WINDOW. THE PUNCTURE WAS LOCATED BETWEEN FRAMES 10 AND 11 AND JUST BELOW STRINGER 18L. REPAIRED IAW ETD2017-170-072268. MAJOR REPAIR.