Narrative:

I have a 1946 piper J3 cub with a hand held radio. I taxied to the end of runway 3 for takeoff which is located about 1 mi from the tower. I called 'ready for takeoff' on tower frequency 126.7 and the tower's reply was unreadable. There was a mooney behind me on the taxiway running up. I switched to ground frequency 121.9 and asked the mooney pilot to relay to the tower that I was ready for takeoff. The mooney pilot answered, 'the tower said you're ready to go.' I then asked the mooney pilot 'does that mean I'm cleared for takeoff?' the mooney pilot answered 'yes, you are cleared for takeoff.' I then switched frequency back to 126.7, checked for traffic visually, and took off. On climb out, I called the tower controller (flying closer to the tower) thinking everything was ok and said 'clarksburg tower you can probably hear me better now, I am requesting a left downwind departure.' the tower controller answered 'cub xyz, you can proceed with a left downwind departure, and be advised that you just took off without a clearance.' shocked, I immediately answered 'the mooney relayed to me that I was cleared for takeoff.' the tower controller answered 'no, I was trying to establish 2-WAY communication and I had not done that.' I then apologized for the takeoff and told him that I really thought I had been cleared for takeoff through the relay. He acknowledged. When I asked for a frequency change I again apologized for the 'miscom.' he acknowledged it. End of incident. At no time were there any traffic conflicts that he made me aware of. Contributing factors: 1) use of handheld radio in a no electric J3 cub at a twred airport, 2) the radio wouldn't work well at the takeoff end of runway 3, 3) asking another pilot to relay communications (this has always worked well for 20 yrs). 4) believing the other pilot when he relayed to me from the tower that I was 'cleared for takeoff' using those exact words. Corrective actions in the future to avoid this incident again: 1) taxi only to an intersection short of the end of runway 3 where 2-WAY communications with a handheld radio are guaranteed. Then when cleared for takeoff by the tower only request to back taxi to the end or take off at the intersection, 2) only take off if the words 'cleared for takeoff' comes from the tower. I will not accept any more relay communications. If I can't communicate with the tower and I'm blocked on the end of the runway, then I'll wait for a light signal for back taxi to ramp or take off.

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Original NASA ASRS Text

Title: A J3 CUB PLT AT CKB ARPT WAS UNABLE TO CONTACT TWR FOR TKOF ON A HANDHELD RADIO AND ASKS A MOONEY PLT TO RELAY. THE MOONEY PLT ERRONEOUSLY TELLS THE J3 PLT HE WAS CLRED FOR TKOF.

Narrative: I HAVE A 1946 PIPER J3 CUB WITH A HAND HELD RADIO. I TAXIED TO THE END OF RWY 3 FOR TKOF WHICH IS LOCATED ABOUT 1 MI FROM THE TWR. I CALLED 'READY FOR TKOF' ON TWR FREQ 126.7 AND THE TWR'S REPLY WAS UNREADABLE. THERE WAS A MOONEY BEHIND ME ON THE TXWY RUNNING UP. I SWITCHED TO GND FREQ 121.9 AND ASKED THE MOONEY PLT TO RELAY TO THE TWR THAT I WAS READY FOR TKOF. THE MOONEY PLT ANSWERED, 'THE TWR SAID YOU'RE READY TO GO.' I THEN ASKED THE MOONEY PLT 'DOES THAT MEAN I'M CLRED FOR TKOF?' THE MOONEY PLT ANSWERED 'YES, YOU ARE CLRED FOR TKOF.' I THEN SWITCHED FREQ BACK TO 126.7, CHKED FOR TFC VISUALLY, AND TOOK OFF. ON CLBOUT, I CALLED THE TWR CTLR (FLYING CLOSER TO THE TWR) THINKING EVERYTHING WAS OK AND SAID 'CLARKSBURG TWR YOU CAN PROBABLY HEAR ME BETTER NOW, I AM REQUESTING A L DOWNWIND DEP.' THE TWR CTLR ANSWERED 'CUB XYZ, YOU CAN PROCEED WITH A L DOWNWIND DEP, AND BE ADVISED THAT YOU JUST TOOK OFF WITHOUT A CLRNC.' SHOCKED, I IMMEDIATELY ANSWERED 'THE MOONEY RELAYED TO ME THAT I WAS CLRED FOR TKOF.' THE TWR CTLR ANSWERED 'NO, I WAS TRYING TO ESTABLISH 2-WAY COM AND I HAD NOT DONE THAT.' I THEN APOLOGIZED FOR THE TKOF AND TOLD HIM THAT I REALLY THOUGHT I HAD BEEN CLRED FOR TKOF THROUGH THE RELAY. HE ACKNOWLEDGED. WHEN I ASKED FOR A FREQ CHANGE I AGAIN APOLOGIZED FOR THE 'MISCOM.' HE ACKNOWLEDGED IT. END OF INCIDENT. AT NO TIME WERE THERE ANY TFC CONFLICTS THAT HE MADE ME AWARE OF. CONTRIBUTING FACTORS: 1) USE OF HANDHELD RADIO IN A NO ELECTRIC J3 CUB AT A TWRED ARPT, 2) THE RADIO WOULDN'T WORK WELL AT THE TKOF END OF RWY 3, 3) ASKING ANOTHER PLT TO RELAY COMS (THIS HAS ALWAYS WORKED WELL FOR 20 YRS). 4) BELIEVING THE OTHER PLT WHEN HE RELAYED TO ME FROM THE TWR THAT I WAS 'CLRED FOR TKOF' USING THOSE EXACT WORDS. CORRECTIVE ACTIONS IN THE FUTURE TO AVOID THIS INCIDENT AGAIN: 1) TAXI ONLY TO AN INTXN SHORT OF THE END OF RWY 3 WHERE 2-WAY COMS WITH A HANDHELD RADIO ARE GUARANTEED. THEN WHEN CLRED FOR TKOF BY THE TWR ONLY REQUEST TO BACK TAXI TO THE END OR TAKE OFF AT THE INTXN, 2) ONLY TAKE OFF IF THE WORDS 'CLRED FOR TKOF' COMES FROM THE TWR. I WILL NOT ACCEPT ANY MORE RELAY COMS. IF I CAN'T COMMUNICATE WITH THE TWR AND I'M BLOCKED ON THE END OF THE RWY, THEN I'LL WAIT FOR A LIGHT SIGNAL FOR BACK TAXI TO RAMP OR TAKE OFF.

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.