Narrative:

Approximately an hour out from ZZZ2 I received a call from the captain that he wanted the flight attendants to walk through the aisle and see if we felt a temperature change (feeling heat) and/or smelling smoke. He got an indicator light from the cargo with a possible fire. It did feel a little warmer in the middle of the cabin going aft. One of the flight attendants thought she smelled a slight smokey smell; but she wasn't sure. When I went to call the captain with this information; he immediately told me we were planning for an emergency and we were currently descending into ZZZ. We had maybe 5 mins in all to prepare the cabin and passenger. We grabbed our manuals; picked up a little in the galleys; and I began to give the emergency PA to the passenger. Due to immediately landing; I followed the PA verbatum; but had no time to do the checklist in order. I immediately turned lights to bright; gave the instructions for the brace position; instructed where the 4 exit doors were; gave specific instruction to the window exit passenger to familiarize themselves with how to open them if instructed by a flight attendant; and then 50 ft from landing commanded the brace position and instructed passenger to stay seated with seat belt until further advised. No evacuate/evacuation necessary; captain did not initiate evacuate/evacuation; no noted fires; smoke; fumes; etc. Cargo checked by ground personnel. Could not find anything. Went to gate where passenger let out into terminal. Later took airplane to ZZZ2.

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Original NASA ASRS Text

Title: APPARENTLY FALSE CARGO FIRE WARNING RESULTS IN MD80 EMERGENCY LANDING AT NEAREST SUITABLE ARPT.

Narrative: APPROX AN HR OUT FROM ZZZ2 I RECEIVED A CALL FROM THE CAPT THAT HE WANTED THE FLT ATTENDANTS TO WALK THROUGH THE AISLE AND SEE IF WE FELT A TEMP CHANGE (FEELING HEAT) AND/OR SMELLING SMOKE. HE GOT AN INDICATOR LIGHT FROM THE CARGO WITH A POSSIBLE FIRE. IT DID FEEL A LITTLE WARMER IN THE MIDDLE OF THE CABIN GOING AFT. ONE OF THE FLT ATTENDANTS THOUGHT SHE SMELLED A SLIGHT SMOKEY SMELL; BUT SHE WASN'T SURE. WHEN I WENT TO CALL THE CAPT WITH THIS INFO; HE IMMEDIATELY TOLD ME WE WERE PLANNING FOR AN EMER AND WE WERE CURRENTLY DSNDING INTO ZZZ. WE HAD MAYBE 5 MINS IN ALL TO PREPARE THE CABIN AND PAX. WE GRABBED OUR MANUALS; PICKED UP A LITTLE IN THE GALLEYS; AND I BEGAN TO GIVE THE EMER PA TO THE PAX. DUE TO IMMEDIATELY LNDG; I FOLLOWED THE PA VERBATUM; BUT HAD NO TIME TO DO THE CHKLIST IN ORDER. I IMMEDIATELY TURNED LIGHTS TO BRIGHT; GAVE THE INSTRUCTIONS FOR THE BRACE POS; INSTRUCTED WHERE THE 4 EXIT DOORS WERE; GAVE SPECIFIC INSTRUCTION TO THE WINDOW EXIT PAX TO FAMILIARIZE THEMSELVES WITH HOW TO OPEN THEM IF INSTRUCTED BY A FLT ATTENDANT; AND THEN 50 FT FROM LNDG COMMANDED THE BRACE POS AND INSTRUCTED PAX TO STAY SEATED WITH SEAT BELT UNTIL FURTHER ADVISED. NO EVAC NECESSARY; CAPT DID NOT INITIATE EVAC; NO NOTED FIRES; SMOKE; FUMES; ETC. CARGO CHKED BY GND PERSONNEL. COULD NOT FIND ANYTHING. WENT TO GATE WHERE PAX LET OUT INTO TERMINAL. LATER TOOK AIRPLANE TO ZZZ2.

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.