Narrative:

Flying from wichita, ks, to ft lauderdale executive. Everything normal, center reported they lost my transponder, I recycled, checked the circuit breaker's, thought it was a transponder failure. A few minutes later I noted the engine RPM gauges were at 2200 RPM, they were set at 2400 RPM. I pushed the propeller levers to full increase, the propellers went to high RPM, still indicated 2200 RPM, knew my problem was larger than on instrument. Then gyro flags came into view lights started dimming. Checking loads on each alternator, showed zero, suspected double alternator failure. Radios were getting weak, I told center I was losing communications, needed a heading for orlando (less busy than tampa). Center cleared me from 9 to 5000 ft. By the time I was at 5000 ft I was in total darkness, even the navigation lights were out. I was flying with a flashlight on my shoulder. During descent I saw the winter haven airport beacon with the runway lights on. I was familiar with it because my younger brother used to flight instruct there. So I decided that landing at an uncontrolled airport was safer than going into mco. I thought the light signal method might not work since my navigation lights were out and they couldn't see me. I also didn't want to disrupt airline traffic unnecessarily, (I'm an ex-airline pilot). So I landed at winter haven, called FSS, advised them I was on the ground safe, told them what happened. After landing and inspecting the engines I notice the left alternator belt had come off and the right one was very loose. I parked the plane, set in the back, got a rent a car and drove the rest of the way to fxe.

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Original NASA ASRS Text

Title: SMA TWIN ACFT LOST ELECTRICAL PWR. PLT ELECTED TO LAND AT UNCTLED ARPT AT NIGHT.

Narrative: FLYING FROM WICHITA, KS, TO FT LAUDERDALE EXECUTIVE. EVERYTHING NORMAL, CENTER RPTED THEY LOST MY TRANSPONDER, I RECYCLED, CHKED THE CB'S, THOUGHT IT WAS A TRANSPONDER FAILURE. A FEW MINUTES LATER I NOTED THE ENG RPM GAUGES WERE AT 2200 RPM, THEY WERE SET AT 2400 RPM. I PUSHED THE PROP LEVERS TO FULL INCREASE, THE PROPS WENT TO HIGH RPM, STILL INDICATED 2200 RPM, KNEW MY PROBLEM WAS LARGER THAN ON INSTRUMENT. THEN GYRO FLAGS CAME INTO VIEW LIGHTS STARTED DIMMING. CHKING LOADS ON EACH ALTERNATOR, SHOWED ZERO, SUSPECTED DOUBLE ALTERNATOR FAILURE. RADIOS WERE GETTING WEAK, I TOLD CENTER I WAS LOSING COMS, NEEDED A HDG FOR ORLANDO (LESS BUSY THAN TAMPA). CENTER CLRED ME FROM 9 TO 5000 FT. BY THE TIME I WAS AT 5000 FT I WAS IN TOTAL DARKNESS, EVEN THE NAV LIGHTS WERE OUT. I WAS FLYING WITH A FLASHLIGHT ON MY SHOULDER. DURING DSCNT I SAW THE WINTER HAVEN ARPT BEACON WITH THE RWY LIGHTS ON. I WAS FAMILIAR WITH IT BECAUSE MY YOUNGER BROTHER USED TO FLT INSTRUCT THERE. SO I DECIDED THAT LNDG AT AN UNCTLED ARPT WAS SAFER THAN GOING INTO MCO. I THOUGHT THE LIGHT SIGNAL METHOD MIGHT NOT WORK SINCE MY NAV LIGHTS WERE OUT AND THEY COULDN'T SEE ME. I ALSO DIDN'T WANT TO DISRUPT AIRLINE TFC UNNECESSARILY, (I'M AN EX-AIRLINE PLT). SO I LANDED AT WINTER HAVEN, CALLED FSS, ADVISED THEM I WAS ON THE GND SAFE, TOLD THEM WHAT HAPPENED. AFTER LNDG AND INSPECTING THE ENGS I NOTICE THE L ALTERNATOR BELT HAD COME OFF AND THE R ONE WAS VERY LOOSE. I PARKED THE PLANE, SET IN THE BACK, GOT A RENT A CAR AND DROVE THE REST OF THE WAY TO FXE.

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.