Narrative:

Shortly after takeoff we noticed a continuous chime which normally is a false lavatory smoke detector and we noted it. In a min or so after the chimes began, the flight attendant was beating on the door. We opened it, she stuck her head in and said there's a fire in the lavatory. We declared an emergency and returned to the field. After getting off the runway, we stopped and called the flight attendants. There was no fire! They hadn't verified, before one sent another to tell us, there was a fire. Their lack of experience and not knowing how these detectors give false warnings sometimes, led to an in-flight return with no problems or injuries!

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Original NASA ASRS Text

Title: AN MLG COMMERCIAL FIXED WING ACFT IN CLB AT 1400 FT DECLARED AN EMER AND DIVERTED DUE TO A RPTED LAVATORY FIRE CAUSED BY A DEFECTIVE LAVATORY SMOKE ALARM.

Narrative: SHORTLY AFTER TKOF WE NOTICED A CONTINUOUS CHIME WHICH NORMALLY IS A FALSE LAVATORY SMOKE DETECTOR AND WE NOTED IT. IN A MIN OR SO AFTER THE CHIMES BEGAN, THE FLT ATTENDANT WAS BEATING ON THE DOOR. WE OPENED IT, SHE STUCK HER HEAD IN AND SAID THERE'S A FIRE IN THE LAVATORY. WE DECLARED AN EMER AND RETURNED TO THE FIELD. AFTER GETTING OFF THE RWY, WE STOPPED AND CALLED THE FLT ATTENDANTS. THERE WAS NO FIRE! THEY HADN'T VERIFIED, BEFORE ONE SENT ANOTHER TO TELL US, THERE WAS A FIRE. THEIR LACK OF EXPERIENCE AND NOT KNOWING HOW THESE DETECTORS GIVE FALSE WARNINGS SOMETIMES, LED TO AN INFLT RETURN WITH NO PROBS OR INJURIES!

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.