Narrative:

I was assigned to the above police helicopter and responding to a crime scene to assist officers with a homicide perimeter. I was communicating on frequency 123.025 with other helicopters at the scene, and at a higher altitude than myself. I was established in a left orbit, approximately 20 degrees of bank, at 60 KTS, and at an altitude of 2200 ft MSL. At the southeast corner of the perimeter orbit, in a bank, my partner (the observer) suddenly yelled at me, 'watch out!' he was pointing to my 2 O'clock position and slightly low. I immediately looked in that direction, and observed an AS350, at my 2 O'clock position, approximately 250 ft laterally, and approximately 100 ft low, passing that position to my front. At a higher speed than my own, it passed us and immediately began an orbit in front of us and slightly outside of our orbit. I had monitored no radio xmissions from him to indicate his intended actions, nor did I receive any xmissions by him at this time to indicate that he had observed me. I idented myself, and told him to take vertical and lateral separation. I idented his aircraft as a tv news helicopter.

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Original NASA ASRS Text

Title: POLICE HELI ORBITING OVER A CRIME SCENE HAS NMAC WITH TV NEWS HELI ARRIVING ON THE SCENE TO ORBIT.

Narrative: I WAS ASSIGNED TO THE ABOVE POLICE HELI AND RESPONDING TO A CRIME SCENE TO ASSIST OFFICERS WITH A HOMICIDE PERIMETER. I WAS COMMUNICATING ON FREQ 123.025 WITH OTHER HELIS AT THE SCENE, AND AT A HIGHER ALT THAN MYSELF. I WAS ESTABLISHED IN A L ORBIT, APPROX 20 DEGS OF BANK, AT 60 KTS, AND AT AN ALT OF 2200 FT MSL. AT THE SE CORNER OF THE PERIMETER ORBIT, IN A BANK, MY PARTNER (THE OBSERVER) SUDDENLY YELLED AT ME, 'WATCH OUT!' HE WAS POINTING TO MY 2 O'CLOCK POS AND SLIGHTLY LOW. I IMMEDIATELY LOOKED IN THAT DIRECTION, AND OBSERVED AN AS350, AT MY 2 O'CLOCK POS, APPROX 250 FT LATERALLY, AND APPROX 100 FT LOW, PASSING THAT POS TO MY FRONT. AT A HIGHER SPD THAN MY OWN, IT PASSED US AND IMMEDIATELY BEGAN AN ORBIT IN FRONT OF US AND SLIGHTLY OUTSIDE OF OUR ORBIT. I HAD MONITORED NO RADIO XMISSIONS FROM HIM TO INDICATE HIS INTENDED ACTIONS, NOR DID I RECEIVE ANY XMISSIONS BY HIM AT THIS TIME TO INDICATE THAT HE HAD OBSERVED ME. I IDENTED MYSELF, AND TOLD HIM TO TAKE VERT AND LATERAL SEPARATION. I IDENTED HIS ACFT AS A TV NEWS HELI.

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.