Narrative:

These 2 helicopter's called inbound to my airspace 1 NM in-trail over the same visual reporting point. This company has their aircraft fly together. So, I assume these aircraft have each other in sight. In this case, that was not so. The rear copter was surprised I didn't issue TA's.

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Original NASA ASRS Text

Title: HTO CTLR FAILS TO ISSUE TA TO CLOSELY SPACED ARR HELI'S ASSUMING THEY HAD EACH OTHER IN SIGHT.

Narrative: THESE 2 HELI'S CALLED INBOUND TO MY AIRSPACE 1 NM IN-TRAIL OVER THE SAME VISUAL RPTING POINT. THIS COMPANY HAS THEIR ACFT FLY TOGETHER. SO, I ASSUME THESE ACFT HAVE EACH OTHER IN SIGHT. IN THIS CASE, THAT WAS NOT SO. THE REAR COPTER WAS SURPRISED I DIDN'T ISSUE TA'S.

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.