Originally Posted by
ATC Watcher
Which safety assessment was made and validated ( and by who) which allowed visual separation for an helicopter at 200ft to pass below the approach path of an aircraft at 3 or 400 feet ?, resulting in a 100-200ft separation ?
None. That would obviously be unsafe, so the helicopter would be expected to use lateral separation. (e.g. "Pass behind the CRJ.")
The 200 ft altitude restriction seems to have given some the impression that helicopters were routinely passing directly below the approach traffic, but that's not the case. And even if it was, it wouldn't really be relevant to this accident. The Blackhawk pilots weren't trying to duck underneath the plane, they never even saw it.