Narrative:

On the night of nov/thu/01, at approximately XA00 local XA30Z) my copilot and myself were holding short of runway 22 at cdw awaiting a VFR clearance for our flight to orh, ma, where we were to pick up 1 passenger. We were monitoring tower on our #1 communication radio and heard the faint voice of cdw tower tell us what we thought was our takeoff clearance. I was unable to hear tower adequately. To the best of my knowledge I read back our takeoff clearance on communication #1 and advised the tower that we were switching radios because we could not hear them adequately. Upon switching radios and positioning on runway 22 myself and my copilot began our takeoff roll. At approximately 1000 ft down the runway tower came over the radio informing us that we had not been cleared for takeoff and had only been cleared to hold in position. We exited on taxiway D to reposition for another takeoff while awaiting a 'release' from ny TRACON for our VFR departure. The safety of this flight was severely jeopardized because our takeoff roll took us across the centerline of runway 9/27 at cdw. This factor in a busy environment could have caused a runway incursion. The principle factor for us beginning the takeoff roll prematurely was a lack of quality communication between flight crew and tower. It is not known why our #1 communication radio appeared to malfunction, however, previous complaints were issued about the radio with ground checks unable to verify a malfunction.

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Original NASA ASRS Text

Title: C310 CREW BEGAN TKOF WITHOUT THE CLR UNDERSTANDING THEY WERE CLRED FOR TKOF.

Narrative: ON THE NIGHT OF NOV/THU/01, AT APPROX XA00 LCL XA30Z) MY COPLT AND MYSELF WERE HOLDING SHORT OF RWY 22 AT CDW AWAITING A VFR CLRNC FOR OUR FLT TO ORH, MA, WHERE WE WERE TO PICK UP 1 PAX. WE WERE MONITORING TWR ON OUR #1 COM RADIO AND HEARD THE FAINT VOICE OF CDW TWR TELL US WHAT WE THOUGHT WAS OUR TKOF CLRNC. I WAS UNABLE TO HEAR TWR ADEQUATELY. TO THE BEST OF MY KNOWLEDGE I READ BACK OUR TKOF CLRNC ON COM #1 AND ADVISED THE TWR THAT WE WERE SWITCHING RADIOS BECAUSE WE COULD NOT HEAR THEM ADEQUATELY. UPON SWITCHING RADIOS AND POSITIONING ON RWY 22 MYSELF AND MY COPLT BEGAN OUR TKOF ROLL. AT APPROX 1000 FT DOWN THE RWY TWR CAME OVER THE RADIO INFORMING US THAT WE HAD NOT BEEN CLRED FOR TKOF AND HAD ONLY BEEN CLRED TO HOLD IN POS. WE EXITED ON TXWY D TO REPOSITION FOR ANOTHER TKOF WHILE AWAITING A 'RELEASE' FROM NY TRACON FOR OUR VFR DEP. THE SAFETY OF THIS FLT WAS SEVERELY JEOPARDIZED BECAUSE OUR TKOF ROLL TOOK US ACROSS THE CTRLINE OF RWY 9/27 AT CDW. THIS FACTOR IN A BUSY ENVIRONMENT COULD HAVE CAUSED A RWY INCURSION. THE PRINCIPLE FACTOR FOR US BEGINNING THE TKOF ROLL PREMATURELY WAS A LACK OF QUALITY COM BTWN FLC AND TWR. IT IS NOT KNOWN WHY OUR #1 COM RADIO APPEARED TO MALFUNCTION, HOWEVER, PREVIOUS COMPLAINTS WERE ISSUED ABOUT THE RADIO WITH GND CHKS UNABLE TO VERIFY A MALFUNCTION.

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.