Narrative:

I was flying north along the hudson on the west side of manhattan, ny. Traditionally, aircraft flying north stay on the east side of the hudson (which I was doing) and sbound aircraft stay on the west side. (Ie, stay to the right). A helicopter was heading sbound in 'my side' at my altitude. I was waiting to see whether he would move to the right. I couldn't move to the right for fear of hitting a building (since I was low) and didn't want to enter controled airspace. About .5 mi away from the helicopter, I veered left and descended. The helicopter looked like a department helicopter because of its blue color. A best solution would be to make the VFR terminal chart depicting this unwritten rule. I also didn't want to turn left because I thought he might turn to his right, therefore we would collide. Also I would then be going in 'the wrong direction,' although I didn't see any other oncoming traffic. (Didn't want to turn left because I might have missed some traffic).

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Original NASA ASRS Text

Title: NMAC BTWN A SMA SEL AND A GOV HELI ALONG HUDSON RIVER CORRIDOR.

Narrative: I WAS FLYING N ALONG THE HUDSON ON THE W SIDE OF MANHATTAN, NY. TRADITIONALLY, ACFT FLYING N STAY ON THE E SIDE OF THE HUDSON (WHICH I WAS DOING) AND SBOUND ACFT STAY ON THE W SIDE. (IE, STAY TO THE R). A HELI WAS HDG SBOUND IN 'MY SIDE' AT MY ALT. I WAS WAITING TO SEE WHETHER HE WOULD MOVE TO THE R. I COULDN'T MOVE TO THE R FOR FEAR OF HITTING A BUILDING (SINCE I WAS LOW) AND DIDN'T WANT TO ENTER CTLED AIRSPACE. ABOUT .5 MI AWAY FROM THE HELI, I VEERED L AND DSNDED. THE HELI LOOKED LIKE A DEPT HELI BECAUSE OF ITS BLUE COLOR. A BEST SOLUTION WOULD BE TO MAKE THE VFR TERMINAL CHART DEPICTING THIS UNWRITTEN RULE. I ALSO DIDN'T WANT TO TURN L BECAUSE I THOUGHT HE MIGHT TURN TO HIS R, THEREFORE WE WOULD COLLIDE. ALSO I WOULD THEN BE GOING IN 'THE WRONG DIRECTION,' ALTHOUGH I DIDN'T SEE ANY OTHER ONCOMING TFC. (DIDN'T WANT TO TURN L BECAUSE I MIGHT HAVE MISSED SOME 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.