Narrative:

Main cargo fire/smoke light position #3, with associated warning lights and fire bell, during climb while en route to mem. We declared an emergency and turned back to the departure airport (msy). We accomplished the fire and smoke checklist and main cargo fire/smoke checklist during high speed descent. Landed runway 19 at msy. We stopped on the runway, shut down the engines and evacuate/evacuationed the aircraft after accomplishing our prebriefed responsibilities from the evacuate/evacuation checklist. We exited the aircraft through the main entry door using the emergency escape slide. We coordinated for fire fighting equipment to be standing by and men and equipment were at the aircraft as we went down the slide. Their subsequent investigation revealed no sign of fire or smoke. In other words -- false alarm!

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Original NASA ASRS Text

Title: A B727-200 FREIGHTER IN CLB AT FL280 DECLARED AN EMER AND DIVERTED DUE A MAIN CARGO FIRE WARNING, LIGHTS AND BELL, CAUSED BY A DEFECTIVE SENSOR.

Narrative: MAIN CARGO FIRE/SMOKE LIGHT POS #3, WITH ASSOCIATED WARNING LIGHTS AND FIRE BELL, DURING CLB WHILE ENRTE TO MEM. WE DECLARED AN EMER AND TURNED BACK TO THE DEP ARPT (MSY). WE ACCOMPLISHED THE FIRE AND SMOKE CHKLIST AND MAIN CARGO FIRE/SMOKE CHKLIST DURING HIGH SPD DSCNT. LANDED RWY 19 AT MSY. WE STOPPED ON THE RWY, SHUT DOWN THE ENGS AND EVACED THE ACFT AFTER ACCOMPLISHING OUR PREBRIEFED RESPONSIBILITIES FROM THE EVAC CHKLIST. WE EXITED THE ACFT THROUGH THE MAIN ENTRY DOOR USING THE EMER ESCAPE SLIDE. WE COORDINATED FOR FIRE FIGHTING EQUIP TO BE STANDING BY AND MEN AND EQUIP WERE AT THE ACFT AS WE WENT DOWN THE SLIDE. THEIR SUBSEQUENT INVESTIGATION REVEALED NO SIGN OF FIRE OR SMOKE. IN OTHER WORDS -- FALSE ALARM!

Data retrieved from NASA's ASRS site as of July 2007 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.