HPN CLRS ACR FOR TKOF THAT CONFLICTS WITH DEPARTING HELI.

Narrative

OUR FLT (ACR X) WAS NEXT FOR DEP FROM RWY 16 AT HPN. LNDG TFC WAS ON FINAL FOR RWY 16 AS WELL. HPN TWR ADVISED OF THE LNDG TFC ON FINAL AND CLRED OUR FLT FOR TKOF; AND TO EXPEDITE THE TKOF ROLL FOR THAT TFC. CLBING THROUGH ABOUT 600 FT MSL (APPROX 200 FT AGL) A HELI AT APPROX 2 O'CLOCK POS AND PARALLELING OUR COURSE APPEARED TO ME. AT THAT TIME; OUR ALT WAS INCREASING TOWARD THEIRS AND OUR SPD APPEARED SOMEWHAT FASTER THAN THE HELI. TWR THEN ASKED IF WE HAD THE HELI IN SIGHT. I WAS PNF AND RESPONDED YES; BUT THAT IT WOULD SEEM NECESSARY TO PASS OUTSIDE OF THE HELI. THIS APPEARED NECESSARY AT THE TIME BECAUSE OUR ALTS AND HDGS WERE APPROX EQUAL; AND OUR SPD WAS HIGHER RELATIVE TO THEIRS; AS IT APPEARED. HOWEVER; AT THIS TIME; WE REACHED 800 FT MSL; WHERE THE SID CALLS FOR A R TURN FROM RWY HDG 162 DEGS TO 320 DEGS. WE MAINTAINED 190 KTS AS PER THE SID. TWR HANDED US OFF TO NEW YORK DEP AND TOLD US TO ADVISE NEW YORK THAT WE HAD HELI IN SIGHT. WE DID SO; AND WERE TOLD TO MAINTAIN VISUAL SEPARATION WITH HELI -- WHICH WE DID. THE TCASII FIRST CALLED 'TFC' AND THEN THE RA COMMANDED 'MONITOR VERT SPD' TO KEEP US CLBING ABOVE THE HELI. THE CAPT REALIZED THAT THE BEST WAY TO COMPLY WITH THE SID AND MAINTAIN VISUAL SEPARATION WAS TO MAKE A R TURN TO PASS BEHIND AND ABOVE THE HELI; WHICH WAS ACCOMPLISHED BY USING A SOMEWHAT MORE AGGRESSIVE TURN AND CLB. WE WRE CLR OF CONFLICT BY APPROX 2000 FT MSL. THIS CONFLICT COULD HAVE BEEN AVOIDED BY HPN TWR DELAYING THE TKOF AND DEP OF EITHER OUR FLT OR THE HELI; EVEN BY AS LITTLE AS 1 MIN. THIS CONFLICT SEEMS TO HAVE BEEN CAUSED BY HPN TWR'S ATTEMPT TO DEPART 2 ACFT INTO A CERTAIN CONFLICT; BASED UPON ADHERENCE TO A PUBLISHED SID. THE TFC BEHIND US ON FINAL FOR RWY 16 SEEMS TO HAVE CONTRIBUTED TO HPN TWR'S DESIRE TO HURRY OUR DEP.