Narrative:

While in cruise flight, returning to nashua (ash) from bridgeport, ct, the radios began to blink on and off and finally went blank. The DME was still working but the vors were displaying an off flag. I assumed at that point that the radios were my only problem so I checked the ammeter but it showed no discharge and then checked the circuit breakers but all were checked in. I then squawked 7700 for 1 min and 7600 for 15 mins, assuming that manchester would receive me on their radar and call nashua. At this point the DME had also stopped working. Approximately 5 mi away from nashua I noticed that my fuel gauges read '0.' I had planned to overfly the field 500 ft above pattern altitude and wait for light signals but upon this discovery, I decided to enter the pattern right away. I next attempted to use my flaps but they did not work. I saw no light signals from the tower but decided to land anyway. Upon shutdown of the aircraft, I noticed the left side of the master switch was off, meaning that the alternator was turned off at some point and I had drained the battery. I had not realized until I was on the ground that I had a complete electrical failure. If I had, I would have possibly been able to recycle the master switch and avoided the situation. I believe that the only way to have prevented this problem would have been to have better assessed the situation I was presented with. I was too quick to accept my first conclusion of radio failure and did not look at the 'big picture.' if I had expected the worst, a total electrical failure, I would have been able to take the necessary steps to have prevented landing in an air traffic area without contacting tower. Also, a better understanding of the aircraft system would have prevented me from entering the pattern without light signals when I noticed the fuel at '0.'

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Original NASA ASRS Text

Title: STUDENT PLT EXERCISES THE LOST COM PROC. ERROR ADMITTED.

Narrative: WHILE IN CRUISE FLT, RETURNING TO NASHUA (ASH) FROM BRIDGEPORT, CT, THE RADIOS BEGAN TO BLINK ON AND OFF AND FINALLY WENT BLANK. THE DME WAS STILL WORKING BUT THE VORS WERE DISPLAYING AN OFF FLAG. I ASSUMED AT THAT POINT THAT THE RADIOS WERE MY ONLY PROB SO I CHKED THE AMMETER BUT IT SHOWED NO DISCHARGE AND THEN CHKED THE CIRCUIT BREAKERS BUT ALL WERE CHKED IN. I THEN SQUAWKED 7700 FOR 1 MIN AND 7600 FOR 15 MINS, ASSUMING THAT MANCHESTER WOULD RECEIVE ME ON THEIR RADAR AND CALL NASHUA. AT THIS POINT THE DME HAD ALSO STOPPED WORKING. APPROX 5 MI AWAY FROM NASHUA I NOTICED THAT MY FUEL GAUGES READ '0.' I HAD PLANNED TO OVERFLY THE FIELD 500 FT ABOVE PATTERN ALT AND WAIT FOR LIGHT SIGNALS BUT UPON THIS DISCOVERY, I DECIDED TO ENTER THE PATTERN RIGHT AWAY. I NEXT ATTEMPTED TO USE MY FLAPS BUT THEY DID NOT WORK. I SAW NO LIGHT SIGNALS FROM THE TWR BUT DECIDED TO LAND ANYWAY. UPON SHUTDOWN OF THE ACFT, I NOTICED THE L SIDE OF THE MASTER SWITCH WAS OFF, MEANING THAT THE ALTERNATOR WAS TURNED OFF AT SOME POINT AND I HAD DRAINED THE BATTERY. I HAD NOT REALIZED UNTIL I WAS ON THE GND THAT I HAD A COMPLETE ELECTRICAL FAILURE. IF I HAD, I WOULD HAVE POSSIBLY BEEN ABLE TO RECYCLE THE MASTER SWITCH AND AVOIDED THE SIT. I BELIEVE THAT THE ONLY WAY TO HAVE PREVENTED THIS PROB WOULD HAVE BEEN TO HAVE BETTER ASSESSED THE SIT I WAS PRESENTED WITH. I WAS TOO QUICK TO ACCEPT MY FIRST CONCLUSION OF RADIO FAILURE AND DID NOT LOOK AT THE 'BIG PICTURE.' IF I HAD EXPECTED THE WORST, A TOTAL ELECTRICAL FAILURE, I WOULD HAVE BEEN ABLE TO TAKE THE NECESSARY STEPS TO HAVE PREVENTED LNDG IN AN ATA WITHOUT CONTACTING TWR. ALSO, A BETTER UNDERSTANDING OF THE ACFT SYS WOULD HAVE PREVENTED ME FROM ENTERING THE PATTERN WITHOUT LIGHT SIGNALS WHEN I NOTICED THE FUEL AT '0.'

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.