If one assumes a worst case scenario of 250 knot traffic, six seconds
works out to 4,167'/second, or 25,000' (greater than 4 nautical
miles).

This sounds like orbital speed.

250 knots is 250 (nautical) miles per HOUR, about 250*6000 feet per
hour, or about 250*100 feet per minute. 25000 feet every sixty seconds,
or 2500 feet every six seconds. Half a mile in six seconds. Opposite
direction traffic at the same speed and your relative change is a mile
in six seconds.

Jose
--
The price of freedom is... well... freedom.
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