Gonzo:
Can you expand your thinking on that one?
Sure.
Aircraft on finals to the left outer, and one ready for take off on the left inner. Once the inbound is within 5nm the outbound cannot take off, as there will be a less-than-5nm conflict if the inbound goes around instead of landing. nb ... The left outbound will have a SID that includes a left turn, because it will need that for separation from the right runway. If there is no turn in SID, then the two runways cannot do simmultaneous departures.
But if the inbound is bound for the left inner, the aircraft ready for take off on left outer can depart if its SID has an immediate turn away from the centerline. So if the inbound goes around (straight ahead), they will be on diverging tracks.
Geffen has said this difference in track has to be 30 degrees, but I am sure I have done SID departures where the stipulation was a 15 degrees turn. Anyone know differently?
And you might ask about sites like LGW, where the guy in front takes off only 2nm in front of you. But as I understand it, this is ok because if you go around ATC will give you an immediate turn away from the aircraft just airborne. But ATC cannot do that at a multi-runway airport, when there are aircraft opperating simultaneously on the right runway.
I hope this sort of makes sense.
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