Narrative:

At approximately FL240 we heard (crew) a loud electrical arc (like a short). It was momentary. We smelled some electrical smoke but saw none. All electrical equipment worked normally. First flight attendant came forward and we felt for hot spots. We checked all electrical system. All checked ok. We ran the cockpit smoke and fire checklist and could find no problems anywhere and the smoke had completely dissipated so since we could find no problems we decided to continue to las. About 1 1/2-3 mins later, there was loud arcing and visible fire and smoke in the overhead just above the cockpit door. The a flight attendant attacked the fire immediately with a halon extinguisher. We declared an emergency and put on our smoke/oxygen masks and turned back to denver. By this time a male flight attendant had come forward to assist in fighting the fire. He used the crash axe to open panels in the overhead to ensure the fire was out. The fire was out but a good deal of smoke remained. The a flight attendant did use a portable bottle extinguisher. During the incident all aircraft system continued to function normally. We returned to denver and made an uneventful landing. The cabin was prepped for evacuate/evacuation but none was required.

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Original NASA ASRS Text

Title: FLC HEARD ARCING AND SMELLED SMOKE AND SMOKE ENTERED COCKPIT. SOME INDICATIONS OF FIRE IN OVERHEAD PANEL. DRY EXTINGUISHER APPLIED. FLT RETURNED TO DEN FOR NORMAL LNDG. NO PAX EVAC.

Narrative: AT APPROX FL240 WE HEARD (CREW) A LOUD ELECTRICAL ARC (LIKE A SHORT). IT WAS MOMENTARY. WE SMELLED SOME ELECTRICAL SMOKE BUT SAW NONE. ALL ELECTRICAL EQUIP WORKED NORMALLY. FIRST FLT ATTENDANT CAME FORWARD AND WE FELT FOR HOT SPOTS. WE CHKED ALL ELECTRICAL SYS. ALL CHKED OK. WE RAN THE COCKPIT SMOKE AND FIRE CHKLIST AND COULD FIND NO PROBLEMS ANYWHERE AND THE SMOKE HAD COMPLETELY DISSIPATED SO SINCE WE COULD FIND NO PROBLEMS WE DECIDED TO CONTINUE TO LAS. ABOUT 1 1/2-3 MINS LATER, THERE WAS LOUD ARCING AND VISIBLE FIRE AND SMOKE IN THE OVERHEAD JUST ABOVE THE COCKPIT DOOR. THE A FLT ATTENDANT ATTACKED THE FIRE IMMEDIATELY WITH A HALON EXTINGUISHER. WE DECLARED AN EMER AND PUT ON OUR SMOKE/OXYGEN MASKS AND TURNED BACK TO DENVER. BY THIS TIME A MALE FLT ATTENDANT HAD COME FORWARD TO ASSIST IN FIGHTING THE FIRE. HE USED THE CRASH AXE TO OPEN PANELS IN THE OVERHEAD TO ENSURE THE FIRE WAS OUT. THE FIRE WAS OUT BUT A GOOD DEAL OF SMOKE REMAINED. THE A FLT ATTENDANT DID USE A PORTABLE BOTTLE EXTINGUISHER. DURING THE INCIDENT ALL ACFT SYS CONTINUED TO FUNCTION NORMALLY. WE RETURNED TO DENVER AND MADE AN UNEVENTFUL LNDG. THE CABIN WAS PREPPED FOR EVAC BUT NONE WAS REQUIRED.

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.