Both planes were turning away from each other at the point where they "lost required separation as the 747 was approaching JFK and shortly after the E170 had taken off from LaGuardia
At their closest, the planes were separated by half a mile horizontally and about 200 feet vertically. FAA regulations state that the planes are required to be at least three miles apart horizontally or 1,000 feet apart vertically.
Phil Demer, the founder of the site NYCAviation.com stated that "New York has a very, very tight airspace." "You're talking about three major, packed airports that are trying to act in unison. It can be very unforgiving."
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