Narrative:

I was over sat arsa and my transmitter first emitted only carrier then nothing. The traffic controller had been talking and understood what was happening. He asked me to press identify if I could read him. I did, and that worked for a while. Eventually, he cleared me free of arsa and told me to squawk 1200, which I did. I continued by pilotage and somewhere several mi north of sat I realized my mode C transponder wasn't working. I spent several mins checking various things and slowly realized I was losing electrical. It was near dusk and I concentrated on my bearing and kept track of where I was on the maps. I know I flew for a period above 10000 ft without a working transponder and I flew for a while only thinking of keeping track and checking the various instruments to see why they weren't working. While this was happening, I eventually dropped altitude to 8500 ft and continued en route. I landed and no problems were encountered on landing. But, I had flown for a time after dark without lights, and not thinking about lights but thinking of where I was and if I was on course or not. After I landed, I realized when the engine went dead the lights on the outside weren't working, so no one could see me.

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Original NASA ASRS Text

Title: SMA LOSING ELECTRICAL CONTINUES ON INTO DARKNESS.

Narrative: I WAS OVER SAT ARSA AND MY XMITTER FIRST EMITTED ONLY CARRIER THEN NOTHING. THE TFC CTLR HAD BEEN TALKING AND UNDERSTOOD WHAT WAS HAPPENING. HE ASKED ME TO PRESS IDENT IF I COULD READ HIM. I DID, AND THAT WORKED FOR A WHILE. EVENTUALLY, HE CLRED ME FREE OF ARSA AND TOLD ME TO SQUAWK 1200, WHICH I DID. I CONTINUED BY PILOTAGE AND SOMEWHERE SEVERAL MI N OF SAT I REALIZED MY MODE C XPONDER WASN'T WORKING. I SPENT SEVERAL MINS CHKING VARIOUS THINGS AND SLOWLY REALIZED I WAS LOSING ELECTRICAL. IT WAS NEAR DUSK AND I CONCENTRATED ON MY BEARING AND KEPT TRACK OF WHERE I WAS ON THE MAPS. I KNOW I FLEW FOR A PERIOD ABOVE 10000 FT WITHOUT A WORKING XPONDER AND I FLEW FOR A WHILE ONLY THINKING OF KEEPING TRACK AND CHKING THE VARIOUS INSTS TO SEE WHY THEY WEREN'T WORKING. WHILE THIS WAS HAPPENING, I EVENTUALLY DROPPED ALT TO 8500 FT AND CONTINUED ENRTE. I LANDED AND NO PROBS WERE ENCOUNTERED ON LNDG. BUT, I HAD FLOWN FOR A TIME AFTER DARK WITHOUT LIGHTS, AND NOT THINKING ABOUT LIGHTS BUT THINKING OF WHERE I WAS AND IF I WAS ON COURSE OR NOT. AFTER I LANDED, I REALIZED WHEN THE ENG WENT DEAD THE LIGHTS ON THE OUTSIDE WEREN'T WORKING, SO NO ONE COULD SEE ME.

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.