Originally Posted by
Luc Lion
Adding an additional slice of cheese in the sandwich is very easy: just state that when 2 tracking routes provide less than 500 ft of separation, then they are mutually exclusive.
This is the really puzzling part. Looking at the expected altitude of an approaching Airliner with a 3° G/S at the expected crossing point it would be at 250 ft +/-50 That leaves a mere 0-100ft to the helicopter route (and that is assuming the Helo path along the East side of the Potomac, if it deviates somewhat to the West the default altitude of the Airliner will drop below 200ft at the crossing). This is simply insane. You could count the number of bolts in the rotor head if everything goes according to plan. If not -well we saw that last night. How can this be allowed? What was the plan? Did ATC assume the Helo would duck under? At night over water? And visual separation in case of a circle to land -not a straight in- at night? Courageous. Note to self: Never take a flight into DCA.