Narrative:

Preparing for a pleasure flight, I had asked for a right turn sbound from runway 2. At the run-up area for runway 2 at hfd I was directed to position and hold, which I acknowledged and proceeded to do. There was an aircraft on final and a helicopter on the grass runway just east of runway 2/20. The tower controller's xmissions had been garbled and indistinct with pilots asking for repeats. When I heard a directive to take off, I acknowledged by announcing with my tail number that I was rolling on runway 2 and applied power to take off. When I was abeam the rising helicopter, at about 50 ft AGL, I was told I had not been cleared to take off and was asked if I had the traffic to my right in sight and I think I was told to report traffic in sight before my right turn. Since I was past the helicopter at this point, and could not see it, I asked if a left turn would be approved. The left turn was approved and I proceeded with my flight. This event could have been avoided by: 1) clear and distinct communication from the tower controller. 2) increased attention on my part. 3) not putting an aircraft in position and hold with both an aircraft on final and a helicopter on the sod awaiting takeoff. 4) the controller immediately informing me that I had not been cleared to take off while I was still on the ground, rather than waiting until I was airborne and nearing conflicting traffic.

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Original NASA ASRS Text

Title: A PA28 PLT HAS AN NMAC AFTER TAKING OFF WITHOUT A CLRNC AT HFD.

Narrative: PREPARING FOR A PLEASURE FLT, I HAD ASKED FOR A R TURN SBOUND FROM RWY 2. AT THE RUN-UP AREA FOR RWY 2 AT HFD I WAS DIRECTED TO POS AND HOLD, WHICH I ACKNOWLEDGED AND PROCEEDED TO DO. THERE WAS AN ACFT ON FINAL AND A HELI ON THE GRASS RWY JUST E OF RWY 2/20. THE TWR CTLR'S XMISSIONS HAD BEEN GARBLED AND INDISTINCT WITH PLTS ASKING FOR REPEATS. WHEN I HEARD A DIRECTIVE TO TAKE OFF, I ACKNOWLEDGED BY ANNOUNCING WITH MY TAIL NUMBER THAT I WAS ROLLING ON RWY 2 AND APPLIED PWR TO TAKE OFF. WHEN I WAS ABEAM THE RISING HELI, AT ABOUT 50 FT AGL, I WAS TOLD I HAD NOT BEEN CLRED TO TAKE OFF AND WAS ASKED IF I HAD THE TFC TO MY R IN SIGHT AND I THINK I WAS TOLD TO RPT TFC IN SIGHT BEFORE MY R TURN. SINCE I WAS PAST THE HELI AT THIS POINT, AND COULD NOT SEE IT, I ASKED IF A L TURN WOULD BE APPROVED. THE L TURN WAS APPROVED AND I PROCEEDED WITH MY FLT. THIS EVENT COULD HAVE BEEN AVOIDED BY: 1) CLR AND DISTINCT COM FROM THE TWR CTLR. 2) INCREASED ATTN ON MY PART. 3) NOT PUTTING AN ACFT IN POS AND HOLD WITH BOTH AN ACFT ON FINAL AND A HELI ON THE SOD AWAITING TKOF. 4) THE CTLR IMMEDIATELY INFORMING ME THAT I HAD NOT BEEN CLRED TO TAKE OFF WHILE I WAS STILL ON THE GND, RATHER THAN WAITING UNTIL I WAS AIRBORNE AND NEARING CONFLICTING TFC.

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.