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And here it is. Instead of Fosters Folly, we now have
Silver's Superhub.
Note the two commuter runways to the north have a separate terminal, to speed the flow of domestic/shengen traffic from the smaller aircraft - so large aircraft do not have to mix with smaller on the same approach. An underground metro would connect the two.
I see no reason for not doing triple simultaneous approaches, as long as the middle stream joins the furthest out, maximising the inbound traffic. Thus, on the commuter runways, the outer runway would be used for arrivals to allow simultaneous approaches, with the inner being for departures.
Note that all the departures (red lines) are over unpopulated areas, to the north, west and south. The blue arrow near Gillingham is the 10nm / 3,000 ft point for arrivals during N.E. landings. This altitude would cause minimal noise nuisance for the Rochester/Gillingham locale.
As to the rail links, the Chunnel line currently goes through Ebbsfleet, just west of Gravesend. A spur would be needed to link to the Silver Superhub Airport, or better still a whole new 'eastern route' that skirts the NE of London to connect to the north.
Links to the west would be via Crossrail. In a fit of planning stupidity, Crossrail ends at Abbey Wood, which is just 12 km short of the Chunnel line at Ebbsfleet. Why??? That is like ending the M6 a couple of miles short of the M1 !! The planners should be introduced to a long rope and a high lamppost. Linking these two lines together, and thence to the TGV spur from Ebbsfleet to the Silver Superhub Airport, would give instant access to the west.
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