Quote:
Originally Posted by bilbao58
All of the runways at LAX are parallel. SFO has crossing runways, which necessarily uses more land area.
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Actually no. With two runways you can use some of the runway area twice. More practically, a cross-runway system doesn't have to worry about parallel traffic streams in low-visibility, so they don't have the factor that drives a lot of the wider spacing elsewhere.
Parallel runways can operate together on instruments if they're 2,500' apart as a baseline, thought that can vary based on other considerations. With visual landings the difference only needs to be 700', again with some added complexities. Any airport with hub ambitions will try for the larger standard.
It looks like the LAX pairs are about 700' and 800' apart btw. The two pairs are more like 4,600 apart, a common feature of "terminal in the middle" design.
As for SFO, on Google Earth I get about 2,100 acres or 3.3. square miles...less than half of the stat in the OP. But they do use the larger figure per Wikipedia. (Edit: per the
map on Page 3 here, the majority of the property is water.)