Narrative:

I had arrived over a scene in ZZZ and was talking to the ground unit and in a r-hand turn conducting my high reconnaissance. My tis activated indicating a possible conflict 300 ft below. I momentarily looked up and around; but saw nothing at that time. I reset the tis but immediately received another alert. At this time I saw a light twin; fixed wing; in a climb out of a small uncontrolled airport; just to the north of my location. The airplane appeared to be headed directly towards me. I made a hard left descending turn; attempting to keep the other aircraft in my sight. It is estimated the airplane passed less than 300 ft away and 50 ft below. It is unknown to me whether this aircraft ever saw me or not. No evasive action was noted.

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Original NASA ASRS Text

Title: WHILE COVERING AN EVENT ON THE GROUND; HELI PLT REPORTS NMAC WITH ACFT DEPARTING AN ARPT NEAR HIS LOCATION.

Narrative: I HAD ARRIVED OVER A SCENE IN ZZZ AND WAS TALKING TO THE GND UNIT AND IN A R-HAND TURN CONDUCTING MY HIGH RECONNAISSANCE. MY TIS ACTIVATED INDICATING A POSSIBLE CONFLICT 300 FT BELOW. I MOMENTARILY LOOKED UP AND AROUND; BUT SAW NOTHING AT THAT TIME. I RESET THE TIS BUT IMMEDIATELY RECEIVED ANOTHER ALERT. AT THIS TIME I SAW A LIGHT TWIN; FIXED WING; IN A CLB OUT OF A SMALL UNCTLED ARPT; JUST TO THE N OF MY LOCATION. THE AIRPLANE APPEARED TO BE HEADED DIRECTLY TOWARDS ME. I MADE A HARD L DSNDING TURN; ATTEMPTING TO KEEP THE OTHER ACFT IN MY SIGHT. IT IS ESTIMATED THE AIRPLANE PASSED LESS THAN 300 FT AWAY AND 50 FT BELOW. IT IS UNKNOWN TO ME WHETHER THIS ACFT EVER SAW ME OR NOT. NO EVASIVE ACTION WAS NOTED.

Data retrieved from NASA's ASRS site as of May 2009 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.