Narrative:

I landed at ZZZ, us, in my C172. After taxiing off runway 1 onto taxiway G, I suffered a complete electrical power failure. My radios failed. (They had been working fine before.) when this happened, I turned the airplane towards the tower and waggled my controls, expecting to see a light. But, error #1, I did not wait very long and, error #2, began taxiing down the taxiway. (I am fairly sure I was cleared to do this before the radio failure, but cannot remember.) then I came to runway 6, where I stopped. I could see my destination FBO directly across the runway. Also, I could see that the runway was clear and that no one was landing on it, it was VFR, but error #3, I treated the situation as similar to my home, uncontrolled airport. Since I could see there was no conflicting traffic, I crossed the runway. I realized immediately that I should not have, but, with no communications I switched to the mode I used at my home, uncontrolled airport, which was safe, but improper in the circumstances. Shortly thereafter I regained electric power and re-established radio communications. (The problem was caused by a defective battery.) the critical failing was my adopting the mode I normally use in a no radio environment when I should not have. Another failure was to give the tower too little time to figure out that I no longer had electric power, and had no radio communications.

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Original NASA ASRS Text

Title: A C172 AFTER LNDG AND TURNING OFF RWY EXPERIENCED COMPLETE ELECTRICAL FAILURE. RPTR TAXIED, CROSSED RWY ALL WITHOUT CTL.

Narrative: I LANDED AT ZZZ, US, IN MY C172. AFTER TAXIING OFF RWY 1 ONTO TXWY G, I SUFFERED A COMPLETE ELECTRICAL PWR FAILURE. MY RADIOS FAILED. (THEY HAD BEEN WORKING FINE BEFORE.) WHEN THIS HAPPENED, I TURNED THE AIRPLANE TOWARDS THE TWR AND WAGGLED MY CTLS, EXPECTING TO SEE A LIGHT. BUT, ERROR #1, I DID NOT WAIT VERY LONG AND, ERROR #2, BEGAN TAXIING DOWN THE TXWY. (I AM FAIRLY SURE I WAS CLRED TO DO THIS BEFORE THE RADIO FAILURE, BUT CANNOT REMEMBER.) THEN I CAME TO RWY 6, WHERE I STOPPED. I COULD SEE MY DEST FBO DIRECTLY ACROSS THE RWY. ALSO, I COULD SEE THAT THE RWY WAS CLR AND THAT NO ONE WAS LNDG ON IT, IT WAS VFR, BUT ERROR #3, I TREATED THE SIT AS SIMILAR TO MY HOME, UNCTLED ARPT. SINCE I COULD SEE THERE WAS NO CONFLICTING TFC, I CROSSED THE RWY. I REALIZED IMMEDIATELY THAT I SHOULD NOT HAVE, BUT, WITH NO COMS I SWITCHED TO THE MODE I USED AT MY HOME, UNCTLED ARPT, WHICH WAS SAFE, BUT IMPROPER IN THE CIRCUMSTANCES. SHORTLY THEREAFTER I REGAINED ELECTRIC PWR AND RE-ESTABLISHED RADIO COMS. (THE PROB WAS CAUSED BY A DEFECTIVE BATTERY.) THE CRITICAL FAILING WAS MY ADOPTING THE MODE I NORMALLY USE IN A NO RADIO ENVIRONMENT WHEN I SHOULD NOT HAVE. ANOTHER FAILURE WAS TO GIVE THE TWR TOO LITTLE TIME TO FIGURE OUT THAT I NO LONGER HAD ELECTRIC PWR, AND HAD NO RADIO COMS.

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.