What was found
THE RT ENGINE EXHAUST TAILPIPE, WAS FOUND TO BE INCORRECTLY INSTALLED OR MANUFACTURED. DURING FLIGHT, THE EXHAUST TAILPIPE CHAFED THE FIREWALL, PN 2813102-8 AND THE FLAME SHIELD, EXHAUST, PN 2813100-13. THE CHAFING PRODUCED A HOLE THROUGH THE FIREWALL. THIS WAS VISUALLY DISCOVERED DURING AN INSPECTION.