Narrative:

I was working in the tower by myself when an air taxi that had just parked at the terminal ramp asked on the frequency if I had talked to an small aircraft that had landed after them and just taxied by. I replied no and asked where the small aircraft parked. When I found out which FBO the small aircraft had taxied to, I called them and spoke to the pilot. The pilot advised me that he had experienced an electrical failure, and therefore had no navigation lights, no radio, non working transponder, etc. Luckily, he was able to land safely and had no impact on other traffic in the air traffic area.

Google
 

Original NASA ASRS Text

Title: SMA ACFT EQUIP PROB ELECTRICAL FAILURE POSSIBLY LANDED ON OCCUPIED RWY WITHOUT CLRNC.

Narrative: I WAS WORKING IN THE TWR BY MYSELF WHEN AN AIR TAXI THAT HAD JUST PARKED AT THE TERMINAL RAMP ASKED ON THE FREQ IF I HAD TALKED TO AN SMA THAT HAD LANDED AFTER THEM AND JUST TAXIED BY. I REPLIED NO AND ASKED WHERE THE SMA PARKED. WHEN I FOUND OUT WHICH FBO THE SMA HAD TAXIED TO, I CALLED THEM AND SPOKE TO THE PLT. THE PLT ADVISED ME THAT HE HAD EXPERIENCED AN ELECTRICAL FAILURE, AND THEREFORE HAD NO NAV LIGHTS, NO RADIO, NON WORKING XPONDER, ETC. LUCKILY, HE WAS ABLE TO LAND SAFELY AND HAD NO IMPACT ON OTHER TFC IN THE ATA.

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.