TFC WATCH ACFT HAS NMAC WITH HELI ALONG HUDSON RIVER CORRIDOR.

Narrative

I WAS CONDUCTING A ROUTINE TFC WATCH FLT WHEN THE SIT OCCURRED. AS ALWAYS WHEN FLYING THIS PARTICULAR RTE; MS A; THE TFC RPTR; WHO ALSO HAPPENS TO BE A STUDENT PLT; WAS ASSISTING ME WITH LOOKING FOR OTHER TFC. WE WERE ABOUT HALFWAY THROUGH THE 2 HR FLT WHEN WE WERE APCHING THE TOWN OF TARRYTOWN FROM THE E; HEADING TOWARDS THE HUDSON RIVER. IT IS A COMMON ROUTINE FOR ALL TFC WATCH PLTS TO BE RPTING POSITIONS ON A JOINT FREQ UNLESS OPERATING IN AIRSPACE WHERE AIR TFC CTL COM IS REQUIRED. I HAD JUST RPTED MY POS ON THIS FREQ; WHEN I NOTICED A HELI COMING MY DIRECTION AND AT MY ALT; AT MY 1-2 O'CLOCK POS. I ESTIMATE THE DISTANCE TO HAVE BEEN 1-1 1/2 MI. MS. A POINTED OUT THE TFC SIMULTANEOUSLY. BECAUSE OF MY POS RELATIVE TO THE HELI; I IMMEDIATELY STARTED A L TURN; WHILE THE HELI; WHOSE PLT APPARENTLY HAD YET NOT SEEN ME; PROCEEDED WITH NO CHANGE IN COURSE. AFTER PASSING THE HELI WITH A SAFE DISTANCE TO HIS R; I SWITCHED TO THE HUDSON RIVER UNICOM; WHICH ALL VFR TFC IS ADVISED TO USE WHEN OPERATING IN THE HUDSON RIVER CORRIDOR. THIS IS ALSO THE FREQ MOST COMMONLY USED BY HELI PLTS; EVEN WHEN NOT OPERATING DIRECTLY OVER THE HUDSON RIVER. ONCE ON THE NEW FREQ; I RPTED MY POS AGAIN; AND ADVISED I WOULD BE XING THE RIVER ON A WESTERLY COURSE. THE HELI PLT THEN FURIOUSLY STATED THAT I HAD ALMOST CAUSED A MID AIR COLLISION. IN THE BRIEF DISCUSSION THAT FOLLOWED; I ASSURED HIM THAT AN ACCIDENT WAS NOWHERE NEAR TO HAVE HAPPENED; AND ADDED WE HAD FOLLOWED THE RECOMMENDED RADIO PROCS. AFTERWARDS; I DISCUSSED THE INCIDENT WITH MS A WHO AGREED THAT IF ANYONE HAD BEEN AT FAULT; IT WAS THE HELI PLT. HE HAD OBVIOUSLY NOT COMPLIED WITH THE BASIC RULE OF SEEING AND AVOIDING. IF HE HAD; HE WOULD UNDOUBTEDLY HAVE CHANGED HIS COURSE OF FLT. I BELIEVE THE FACTORS CONTRIBUTING TO THIS SIT PRIMARILY ARE AS FOLLOWS: THE HIGH DENSITY OF VFR TFC OPERATING IN THE NEW YORK METROPOLITAN AREA; THE FACT THAT HELI PLTS; FULLY AWARE OF THE RADIO PROCS CONDUCTED BY FIXED WING TFC RPTR PLTS AS WELL AS THEIR FREQUENCIES; ARE FAILING TO CHANGE FREQS ONCE OUTSIDE THE HUDSON RIVER CORRIDOR.