Narrative:

I received taxi clearance from ramp to intersection a via taxiway D. I held aircraft short of runway 18L and called tower on 118.1. I thought I heard a clear to take off from the tower. Right seat pilot (IFR rated) also thought we had been cleared for takeoff. Upon liftoff, we had a total (electrical power) failure. Landed ok using portable radio. After landing we were told the takeoff clearance was for another plane with a similar tail number. We think the electrical problem may have contributed to our misunderstanding.

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Original NASA ASRS Text

Title: PLT TAKES OFF WITH CLRNC GIVEN ACFT WITH SIMILAR CALL SIGN AND BLAMES IT ON AN ELECTRICAL FAILURE AFTER TKOF.

Narrative: I RECEIVED TAXI CLRNC FROM RAMP TO INTXN A VIA TXWY D. I HELD ACFT SHORT OF RWY 18L AND CALLED TWR ON 118.1. I THOUGHT I HEARD A CLR TO TAKE OFF FROM THE TWR. R SEAT PLT (IFR RATED) ALSO THOUGHT WE HAD BEEN CLRED FOR TKOF. UPON LIFTOFF, WE HAD A TOTAL (ELECTRICAL PWR) FAILURE. LANDED OK USING PORTABLE RADIO. AFTER LNDG WE WERE TOLD THE TKOF CLRNC WAS FOR ANOTHER PLANE WITH A SIMILAR TAIL NUMBER. WE THINK THE ELECTRICAL PROB MAY HAVE CONTRIBUTED TO OUR MISUNDERSTANDING.

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.