Narrative:

100 NM mi west of ZZZ at 35000 ft; just prior to initial descent; the master warning; aft cargo fire light and aural warning came on. Started cargo fire checklist and declared emergency. Performed an emergency descent and landed on runway xx at ZZZ. During descent; the fire bottles were deployed to aft cargo bay. The fire warning was initially intermittent; but within 5 mins came on continuously and never went out. The aural warning had to be reset multiple times. The flight attendants confirmed no indications of fire throughout descent and landing. After landing the fire department opened aft cargo bay and confirmed no fire. We elected not to ground egress. The passenger bags were pulled out and aft bay inspected. There were no indications of fire; so the aircraft was towed to the gate.

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Original NASA ASRS Text

Title: MD80 FLT CREW REPORTS AFT CARGO FIRE WARNING AT FL350 AND FOLLOWS CHECKLIST PROCEDURES DURING AN EMERGENCY DESCENT. POST FLIGHT INSPECTION REVEALS FALSE WARNING.

Narrative: 100 NM MI W OF ZZZ AT 35000 FT; JUST PRIOR TO INITIAL DSCNT; THE MASTER WARNING; AFT CARGO FIRE LIGHT AND AURAL WARNING CAME ON. STARTED CARGO FIRE CHKLIST AND DECLARED EMER. PERFORMED AN EMER DSCNT AND LANDED ON RWY XX AT ZZZ. DURING DSCNT; THE FIRE BOTTLES WERE DEPLOYED TO AFT CARGO BAY. THE FIRE WARNING WAS INITIALLY INTERMITTENT; BUT WITHIN 5 MINS CAME ON CONTINUOUSLY AND NEVER WENT OUT. THE AURAL WARNING HAD TO BE RESET MULTIPLE TIMES. THE FLT ATTENDANTS CONFIRMED NO INDICATIONS OF FIRE THROUGHOUT DSCNT AND LNDG. AFTER LNDG THE FIRE DEPT OPENED AFT CARGO BAY AND CONFIRMED NO FIRE. WE ELECTED NOT TO GND EGRESS. THE PAX BAGS WERE PULLED OUT AND AFT BAY INSPECTED. THERE WERE NO INDICATIONS OF FIRE; SO THE ACFT WAS TOWED TO THE GATE.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.