Narrative:

Departing runway 24 at carbon pale right after takeoff (leaving 75/100) a curl of smoke came from avionics area. I reduced the power to possibly land straight ahead on runway. The wisp became a torrent. I turned off avionics master switch. No change. Avionics back on, I announced to tower that I had an electrical fire and was landing on runway 6. 'Cleared to land,' tower said. I turned 30 degrees right and then quickly reversed course and set up for landing. Smoke was now thick and I turned off both the avionics master and the aircraft master switches. The landing was normal and I turned off at the midfield taxiway. Molten insulation, still afire, was dripping on my right leg and foot on final and during rollout. After stopping the aircraft I yelled for a fire extinguisher as my wife and 20 month old daughter (and I) left the aircraft. 2 shots of dry chemical killed the fire. No injuries or damage, but I wonder why the circuit breaker's didn't perform their proper function. The 50 amp alternator breaker seemed to be very hot to the touch and the plastic around the retainer nut was charred and sunken. We weren't in the air 3 mins. Amazing how fast a problem can become a real emergency. I thanked tower (by phone) for not landing one of trainers opp direction. Callback conversation with reporter revealed the following: several mechanics looked at the aircraft and finally 2 of them agreed that the source of the short circuit was the solenoid on the starter that did to release. Apparently the starter then becomes a giant gen in reverse. Still unknown why the circuit breaker's failed. It may be the enormous surge of energy froze the circuit breaker. An uncommon occurrence, but experienced pilots have told me they have heard of it happening on older models of this type aircraft.

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Original NASA ASRS Text

Title: SMOKE EVIDENT ON TKOF. PLT IMMEDIATELY RETURNED LANDED WITH SMOKE INCREASING AND MOLTEN PLASTIC DRIPPING ON LEG AND FOOT. BRINGING THE ACFT TO A STOP THE SMOKE AND FIRE WAS QUICKLY EXTINGUISHED AS PLT AND 2 PAX LEFT THE AFT. TIME IN AIR, 3 MINS.

Narrative: DEPARTING RWY 24 AT CARBON PALE RIGHT AFTER TKOF (LEAVING 75/100) A CURL OF SMOKE CAME FROM AVIONICS AREA. I REDUCED THE PWR TO POSSIBLY LAND STRAIGHT AHEAD ON RWY. THE WISP BECAME A TORRENT. I TURNED OFF AVIONICS MASTER SWITCH. NO CHANGE. AVIONICS BACK ON, I ANNOUNCED TO TWR THAT I HAD AN ELECTRICAL FIRE AND WAS LNDG ON RWY 6. 'CLRED TO LAND,' TWR SAID. I TURNED 30 DEGS RIGHT AND THEN QUICKLY REVERSED COURSE AND SET UP FOR LNDG. SMOKE WAS NOW THICK AND I TURNED OFF BOTH THE AVIONICS MASTER AND THE ACFT MASTER SWITCHES. THE LNDG WAS NORMAL AND I TURNED OFF AT THE MIDFIELD TXWY. MOLTEN INSULATION, STILL AFIRE, WAS DRIPPING ON MY RIGHT LEG AND FOOT ON FINAL AND DURING ROLLOUT. AFTER STOPPING THE ACFT I YELLED FOR A FIRE EXTINGUISHER AS MY WIFE AND 20 MONTH OLD DAUGHTER (AND I) LEFT THE ACFT. 2 SHOTS OF DRY CHEMICAL KILLED THE FIRE. NO INJURIES OR DAMAGE, BUT I WONDER WHY THE CB'S DIDN'T PERFORM THEIR PROPER FUNCTION. THE 50 AMP ALTERNATOR BREAKER SEEMED TO BE VERY HOT TO THE TOUCH AND THE PLASTIC AROUND THE RETAINER NUT WAS CHARRED AND SUNKEN. WE WEREN'T IN THE AIR 3 MINS. AMAZING HOW FAST A PROB CAN BECOME A REAL EMER. I THANKED TWR (BY PHONE) FOR NOT LNDG ONE OF TRAINERS OPP DIRECTION. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: SEVERAL MECHS LOOKED AT THE ACFT AND FINALLY 2 OF THEM AGREED THAT THE SOURCE OF THE SHORT CIRCUIT WAS THE SOLENOID ON THE STARTER THAT DID TO RELEASE. APPARENTLY THE STARTER THEN BECOMES A GIANT GEN IN REVERSE. STILL UNKNOWN WHY THE CB'S FAILED. IT MAY BE THE ENORMOUS SURGE OF ENERGY FROZE THE CB. AN UNCOMMON OCCURRENCE, BUT EXPERIENCED PLTS HAVE TOLD ME THEY HAVE HEARD OF IT HAPPENING ON OLDER MODELS OF THIS TYPE ACFT.

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.