Narrative:

The flight had been at cruise only a couple of mins when the fire warning bell sounded and the 'wheelwell fire' warning light illuminated. We accomplished the qrc and QRH procedures, extended the landing gear after slowing the aircraft, but the fire warning light remained illuminated. We started to descend to a lower altitude, declared an emergency with mazatlan center, and coordinated our diversion with maintenance control and company dispatch. Mazatlan was the closest suitable airport 'in point of time.' we coordinated a low altitude 'fly-by' over the tower, who reported that our landing gear appeared to be normal and undamaged. The 'wheelwell fire' warning light finally extinguished as we approached mazatlan airport (approximately 20 mins after illuminating). I briefed the flight attendants that we were making a 'precautionary landing,' and a normal flaps 40 degree landing was accomplished on runway 26 without incident. We had requested that the tower have emergency vehicles standing by, but they were not there. A normal taxi to the gate was accomplished. Postflt inspection revealed no apparent damage or apparent cause for the fire indication.

Google
 

Original NASA ASRS Text

Title: A B737-300 FLC DIVERTS BECAUSE OF AN INDICATION OF A WHEELWELL FIRE WARNING, ONLY TO FIND THAT IT WAS A FALSE WARNING AFTER LNDG AT MMMZ, FO.

Narrative: THE FLT HAD BEEN AT CRUISE ONLY A COUPLE OF MINS WHEN THE FIRE WARNING BELL SOUNDED AND THE 'WHEELWELL FIRE' WARNING LIGHT ILLUMINATED. WE ACCOMPLISHED THE QRC AND QRH PROCS, EXTENDED THE LNDG GEAR AFTER SLOWING THE ACFT, BUT THE FIRE WARNING LIGHT REMAINED ILLUMINATED. WE STARTED TO DSND TO A LOWER ALT, DECLARED AN EMER WITH MAZATLAN CTR, AND COORDINATED OUR DIVERSION WITH MAINT CTL AND COMPANY DISPATCH. MAZATLAN WAS THE CLOSEST SUITABLE ARPT 'IN POINT OF TIME.' WE COORDINATED A LOW ALT 'FLY-BY' OVER THE TWR, WHO RPTED THAT OUR LNDG GEAR APPEARED TO BE NORMAL AND UNDAMAGED. THE 'WHEELWELL FIRE' WARNING LIGHT FINALLY EXTINGUISHED AS WE APCHED MAZATLAN ARPT (APPROX 20 MINS AFTER ILLUMINATING). I BRIEFED THE FLT ATTENDANTS THAT WE WERE MAKING A 'PRECAUTIONARY LNDG,' AND A NORMAL FLAPS 40 DEG LNDG WAS ACCOMPLISHED ON RWY 26 WITHOUT INCIDENT. WE HAD REQUESTED THAT THE TWR HAVE EMER VEHICLES STANDING BY, BUT THEY WERE NOT THERE. A NORMAL TAXI TO THE GATE WAS ACCOMPLISHED. POSTFLT INSPECTION REVEALED NO APPARENT DAMAGE OR APPARENT CAUSE FOR THE FIRE INDICATION.

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.