As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON ROUTINE INSPECTION, FOUND APU DUCT CRACKED AT 'Y' JUNCTION. CRACK WAS APPROXIMATELY .50 INCH LONG AND HAD OPENED UP TO APPROXIMATELY .1532 INCH ALLOWING EXTREMELY HOT BLEED AIR FROM APU TO BLOW THROUGH INSULATION ON THE DUCT INTO THE TAIL COMPARTMENT OF THE AIRCRAFT.