As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PHL - FLT NR 0298 - ON APPROACH, CREW RECEIVED AND APU FIRE INDICATION. THE APU AUTOMATICALLY SHUTDOWN AND THE BOTTLE FIRED, P/N 33100007. THERE WERE NO OTHER INDICATIONS OF A FIRE. MAINTENANCE INSPECTED THE APU FIRE EXIT SYSTEM. THE FIRE EXTINGUISHER BOTTLE WAS REPLACED. OPERATIONS CHECKED GOOD. (M)