Narrative:

Firstly, a student and I were working on pilotage skills and attempting to find our way to hwv, on long island, while under the floor of class C isp at 1200 ft, and nearly wandered into the surface area surrounding isp after we confused some radio towers marked on the sectional for towers that were actually farther east. A look at our GPS told us a 130 degree heading would take us to hwv, which was unexpected and, therefore, a bit unnerving. Nevertheless, we quickly spotted hwv now that we were looking in the right direction, called in for TA's at about 5 mi northwest and started setting up for a left downwind entry for runway 6, when it was announced there would be a switch to left traffic for runway 15. No problem, my student quickly made the necessary adjustments, and we went in for a touch-and-go. As we were taking off and approaching 300 ft, I saw a helicopter at 500 ft directly in front of us (maybe 1/4 mi). I was not sure exactly what to do as this was my first time to hwv. We had no more runway in front of us to land, I didn't want to go below the helicopter, fearing its vortices, but that was my only option at the moment. I then looked right and saw no obstacles, made a steep turn -- not my favorite thing to do less than 200 ft above the trees, but at least it would take me on a course behind the helicopter and not back into traffic that was on the left downwind. And I don't think I actually had to turn too far off course before it was clear the helicopter was no longer a factor. I then made a radio call to warn the other aircraft in the pattern about the helicopter. Thinking back on it, I should have mentioned that it was transitioning to the north, to warn anyone in the left downwind, but I didn't. Anyway, it seems clear that the helicopter heard runway 6 was in use and flew at 500 ft parallel to and south of the runway (a safe move as traffic was flying left turns at 1000 ft). However, it must not have been monitoring CTAF, and did not hear about the change to runway 15, which then put it right over the departure end of the runway. Hope this is helpful.

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Original NASA ASRS Text

Title: DA20 FLC HAS NMAC AT HWV.

Narrative: FIRSTLY, A STUDENT AND I WERE WORKING ON PILOTAGE SKILLS AND ATTEMPTING TO FIND OUR WAY TO HWV, ON LONG ISLAND, WHILE UNDER THE FLOOR OF CLASS C ISP AT 1200 FT, AND NEARLY WANDERED INTO THE SURFACE AREA SURROUNDING ISP AFTER WE CONFUSED SOME RADIO TWRS MARKED ON THE SECTIONAL FOR TWRS THAT WERE ACTUALLY FARTHER E. A LOOK AT OUR GPS TOLD US A 130 DEG HDG WOULD TAKE US TO HWV, WHICH WAS UNEXPECTED AND, THEREFORE, A BIT UNNERVING. NEVERTHELESS, WE QUICKLY SPOTTED HWV NOW THAT WE WERE LOOKING IN THE RIGHT DIRECTION, CALLED IN FOR TA'S AT ABOUT 5 MI NW AND STARTED SETTING UP FOR A L DOWNWIND ENTRY FOR RWY 6, WHEN IT WAS ANNOUNCED THERE WOULD BE A SWITCH TO L TFC FOR RWY 15. NO PROB, MY STUDENT QUICKLY MADE THE NECESSARY ADJUSTMENTS, AND WE WENT IN FOR A TOUCH-AND-GO. AS WE WERE TAKING OFF AND APCHING 300 FT, I SAW A HELI AT 500 FT DIRECTLY IN FRONT OF US (MAYBE 1/4 MI). I WAS NOT SURE EXACTLY WHAT TO DO AS THIS WAS MY FIRST TIME TO HWV. WE HAD NO MORE RWY IN FRONT OF US TO LAND, I DIDN'T WANT TO GO BELOW THE HELI, FEARING ITS VORTICES, BUT THAT WAS MY ONLY OPTION AT THE MOMENT. I THEN LOOKED R AND SAW NO OBSTACLES, MADE A STEEP TURN -- NOT MY FAVORITE THING TO DO LESS THAN 200 FT ABOVE THE TREES, BUT AT LEAST IT WOULD TAKE ME ON A COURSE BEHIND THE HELI AND NOT BACK INTO TFC THAT WAS ON THE L DOWNWIND. AND I DON'T THINK I ACTUALLY HAD TO TURN TOO FAR OFF COURSE BEFORE IT WAS CLR THE HELI WAS NO LONGER A FACTOR. I THEN MADE A RADIO CALL TO WARN THE OTHER ACFT IN THE PATTERN ABOUT THE HELI. THINKING BACK ON IT, I SHOULD HAVE MENTIONED THAT IT WAS TRANSITIONING TO THE N, TO WARN ANYONE IN THE L DOWNWIND, BUT I DIDN'T. ANYWAY, IT SEEMS CLR THAT THE HELI HEARD RWY 6 WAS IN USE AND FLEW AT 500 FT PARALLEL TO AND S OF THE RWY (A SAFE MOVE AS TFC WAS FLYING L TURNS AT 1000 FT). HOWEVER, IT MUST NOT HAVE BEEN MONITORING CTAF, AND DID NOT HEAR ABOUT THE CHANGE TO RWY 15, WHICH THEN PUT IT RIGHT OVER THE DEP END OF THE RWY. HOPE THIS IS HELPFUL.

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.