As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU FIREWALL UPPER FLANGE IS CRACKED 0.400" & LOWER FLANGE IS CRACKED 0.500". X=26290.0. BOTH CRACKS ROUTED OUT AND NDT PERFORMED VERIFYING NO MORE CRACKING EXISTS ON WO 693815-313 IAW ETD 2013-170-004515 AND COMPASS EA E170-53-021 REV IR WO 708770.