As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LOUVER ASSEMBLY AND EXHAUST DUCTS DAMAGED WHEN TURBINE BROKE OFF FROM THE APU. *S/D* UNITED NO LONGER USES (P/N 3606982-1) AND NOW USES(P/N 3842072-2 OR - 3). THE PROBLEM HAS BEEN ADDRESSED AND ALL MEANS OF INSPECTION AND REPAIR OF SADDLE CRACKS ARE IN PLACE. THE 98CK APU BEING INSTALLED ON 727-222 AIRPLANES HAS TAILPIPES WITH CENTER BODIES INSTALLED TO PREVENT RELEASE OF SHRAPNEL IN CASE OF TURBINE WHEEL DISPERSEMENT.