Mon Jan 11, 2021 9:02 am
Well... let's see.
How many arrivals do you get? What's your ideal AAR?
Are these runways parallel? Where is each intersection of crossing runways?
If these runways are parallel, what sort of approaches do you need? Are we talking simultaneous instruments (many), or trips (DFW), or quads (ORD), or just one instrument and the rest tied visual (BOS)?
If you've got parallels, how far apart are they? Can you comfortably work your volume with that under 2500ft same runway separation rule, or do you need to build a new runway 2501ft away from your existing one (DFW)? Or maybe you need a third parallel. That's the ticket (SEA). Let's build a frickin' island and stick that sucker on there.
Do you need an offset due to departure procedures and missed approach procedures (JFK)?
What's the noise situation? Is one runway entirely useless for departures because of De Blasio (I'm kidding)?
Or, do you just hang on to vestigial runways because they're sentimental and remind you of a different, simpler time (MSP, DTW, LGW)?
Perhaps you have runways going in every single direction because YOLO and we're on a manmade island (BOS)?
There is no answer to your question.