Jabird:
I can't get a scale plan of the Foster proposals, but the general format for a midfield terminal between parallel runways seems to be to go for around 1km.
This is one of the big problems with Foster, which I have been trying to tell them about for months. The minimum requirement for simultaneous opps is 1.5 km between the runways, and this is why Heathrow has a problem, being only 1.4 km between the runways.
So Foster is not only proposing an airport that cannot run simultaneous opps, he is also inviting the same huge LHR problems of narrow taxiways and not enough stands. Not sure if you are all aware, but B747s were not allowed to taxi on the LHR inner until 1995, because there was no room. And even after the amended the layout to allow it, I always got the feeling that someone not on the centerline would take our tail off.
If we are designing an airport for the next century, we need as much room as possible, which is why I had the 5-6 runway layout, and an airport at least 4 km across (three groups of runways with 2km between each group).
Plus, of course, this layout will allow separation of domestic short-haul mediums and long-haul heavies - for greater traffic flow. And also for overcoming this mad idea that someone coming in international, and going out international has to clear customs and immigration. Why? Nobody has explained to me why so many countries do this. With a fully international terminal, someone coming in from the States and going out to the Middle East could stay airside with no checks (apart, perhaps, from a security screen.)
Foster is simply not looking ahead enough. Simply moving LHR to the Isle of Grain, while retaining all the limitations and restrictions that LHR has, will not help anyone.
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