As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EVIDENCE OF EXHAUST LEAK AT APU ELBOW TO LOWER BELLOWS FLANGE AREA. FOUND SEARED BOLTS ON ELBOW FLANGE. REMOVED ELBOW. FOUND ELBOW FLANGE CRACKED 360 DEGREES. REMOVED 5 EA NUT PLATES WITH SHEARED STUDS AND REPLACED NUT PLATES. INSTALLED ELBOW ASSY IN THE EXHAUST IAW AMM 49-81-02-400-801. LEAK CHECK OK.