F100 DIVERTS TO LIT WITH ELECTRICAL SMOKE IN COCKPIT AND CABIN.

Narrative

WHILE ENRTE DFW/SDF AT FL330 THE FO AND I BOTH NOTICED A STRONG ODOR IN THE COCKPIT SUGGESTING AN ELECTRICAL BURNING COMPONENT; LOCATION UNKNOWN. NO ABNORMAL INDICATIONS WERE NOTED AND NO CIRCUIT BREAKERS POPPED. WITHIN SECONDS; THE SENIOR FLT ATTENDANT IN THE CABIN CALLED TO INFORM ME OF THE SAME ODOR IN THE MAIN CABIN; NOTING THAT THE GALLEYS WERE SECURE AND THE PROB WAS NOT ORIGINATING FROM THAT LOCATION. NO SMOKE WAS VISIBLE IN EITHER THE COCKPIT OR CABIN. I IMMEDIATELY ASKED THE FO TO GET A CLRNC FROM ZME INTO LIT; APPROX 15 MI SE OF OUR POS; WITH AN IMMEDIATE DSCNT. AN UNINTERRUPTED DSCNT ENSUED WITH CLRNC FROM THE CTR AND NO EMER WAS DECLARED. THE COCKPIT/CABIN FIRE/SMOKE CHKLIST WAS RUN AS A PRECAUTION; AND THE ODOR BEGAN TO DIMINISH AFTER ABOUT 5 MINS. COORDINATED THE TIME REMAINING WITH THE #1 FLT ATTENDANT AND GOT UPDATES ON THE CABIN CONDITION DURING THE DSCNT. LANDED STRAIGHT-IN ON LIT RWY 22L ON A VISUAL APCH. WX WAS PERFECT. TIME FROM INITIAL NOTICE OF ODOR UNTIL LNDG WAS ABOUT 7 MINS. CFR WAS ROUTINELY PRESENT BUT NO ASSISTANCE WAS NEEDED; AND AT NO TIME DID AN EVAC APPEAR NECESSARY. AFTER LNDG; I CHKED WITH THE FLT ATTENDANT TO GET A NEW CABIN ASSESSMENT AND SHE SAID THE ODOR HAD ABATED SUBSTANTIALLY. A NON REVENUE PLT IN THE CABIN ALSO VERIFIED THE ODOR AS ELECTRICAL IN NATURE. WE PARKED AT THE GATE AND CONTRACT MAINT SUBSEQUENTLY FOUND A POSSIBLE CAUSE BUT COULD NOT SAY FOR SURE WHAT THE CULPRIT WAS. THEY DISCOVERED A DC PWR SUPPLY COOLING FAN HAD FAILED; BUT THERE WAS NO ODOR DETECTED WITHIN THE UNIT ALTHOUGH IT WAS STILL NOTICEABLE IN THE COCKPIT.