Narrative:

We witnessed the following, but potentially could have been involved. The ramp at ito is not controled by ATC. Acrs operate adjacent to a commuter ramp that is primarily used by tour helicopter operations. 2 tour helicopters departed simultaneously as we began to pull out of our spot at the gate. We called for a taxi clearance (while still in the uncontrolled area). Tower did not have a chance to respond to us as helicopter 'a' came on the frequency and inquired where helicopter 'B' was going. They appeared to be on a converging course and both heading in our direction. This is normal departure flow and they are usually instructed to not overfly us -- though I have not seen 2 depart at the same time before. Helicopter 'B' proceeded in and helicopter 'a' took the diversionary action. We didn't hear the communications to tower prior to our own movement, so we don't know how these 2 simultaneous departures came about, but this confined area probably ought to be a controled movement area. We came to a stop when tower didn't answer, but didn't have any option out of this if helicopter 'a' had not turned away.

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Original NASA ASRS Text

Title: AN ACR DC9 CAPT RPTS WITNESSING AN NMAC BTWN 2 SIGHTSEEING HELIS WHO WERE DEPARTING AT THE SAME TIME TOWARD THE ACR TERMINAL.

Narrative: WE WITNESSED THE FOLLOWING, BUT POTENTIALLY COULD HAVE BEEN INVOLVED. THE RAMP AT ITO IS NOT CTLED BY ATC. ACRS OPERATE ADJACENT TO A COMMUTER RAMP THAT IS PRIMARILY USED BY TOUR HELI OPS. 2 TOUR HELIS DEPARTED SIMULTANEOUSLY AS WE BEGAN TO PULL OUT OF OUR SPOT AT THE GATE. WE CALLED FOR A TAXI CLRNC (WHILE STILL IN THE UNCTLED AREA). TWR DID NOT HAVE A CHANCE TO RESPOND TO US AS HELI 'A' CAME ON THE FREQ AND INQUIRED WHERE HELI 'B' WAS GOING. THEY APPEARED TO BE ON A CONVERGING COURSE AND BOTH HDG IN OUR DIRECTION. THIS IS NORMAL DEP FLOW AND THEY ARE USUALLY INSTRUCTED TO NOT OVERFLY US -- THOUGH I HAVE NOT SEEN 2 DEPART AT THE SAME TIME BEFORE. HELI 'B' PROCEEDED IN AND HELI 'A' TOOK THE DIVERSIONARY ACTION. WE DIDN'T HEAR THE COMS TO TWR PRIOR TO OUR OWN MOVEMENT, SO WE DON'T KNOW HOW THESE 2 SIMULTANEOUS DEPS CAME ABOUT, BUT THIS CONFINED AREA PROBABLY OUGHT TO BE A CTLED MOVEMENT AREA. WE CAME TO A STOP WHEN TWR DIDN'T ANSWER, BUT DIDN'T HAVE ANY OPTION OUT OF THIS IF HELI 'A' HAD NOT TURNED AWAY.

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.