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.