Gonzo:
If the routes of successive departuresfrom the same runway do not diverge 45 degrees then you must leave 2 minutes between them. From the same runway.
And dolphins swim....
This would happen to any airfield anywhere, and is not a specific problem to a Thames airport.
Gozo:
Then I suggest you should never fly into a capacity constrained airport in CATIII. To give you a landing clearance at 4nm, then we'd have to apply spacing of 8-9nm between lanbdings, not 6nm, in CATIII. LHR's CATIII capacity would go down even more.
And a better explanation for why LHR should be closed down would be harder to find.
Just because capacity restraints have influenced a legal administrator to write a paragraph declaring a 1nm clearance to land on a Cat III approach to be 'legal', does not make it 'right' nor 'safe'. Likewise with LGW clearing you to land an allowing you to land with another aircraft sitting on the runway.
These are merely signs and warnings that we should be designing a new airport with much greater capacity, and now.
Man7:
Something to consider that I dont think has been mentioned yet is where is all the rock and cement going to come from to create the island ?
Jabird:
Yes, good point. SS had obviously been listening to the Shamen's 'Move any Mountain' - yet he denies there are any mountains, or any kind of contours in the Thames Estuary!
They would use sand, of which there is plenty in the region. The Dutch use sand to build new land, as they are doing around Amsterdam right now. The only problem being that the sand takes 10 years to settle (using water wicks), and so you need to build the island NOW, if you want construction to start in early 2020. I think the vibrational method is quicker, but the water wick is certainly the cheapest.
Actually, this is not a good point, Jabird. Sand is one of the strongest and most stable foundations you can have, if you compact it and stabilise it well enough. Just in case you are unaware, this thing is built upon sand - yes, sand:
Fairdeal:
(1) There are already FOUR airports east of London: London (LCY), Manston, Southend, and Stansted. Why do we need a fifth? What would be the implications for air traffic control with five airports so close to each other?
(3) If an airport so far away from London is really acceptable, it's better to use Farnborough, Hurn (Bournemouth) or Manston. These airports already have runways capable of taking the largest jets.
Please read the thread, before jumping in, most of your points have already been answered.
Expansion of other small airports is not what is needed. LHR expansion is about capturing the international traffic and funnelling them efficiently into London or onto interlining flights and TGV trains to the rest of Europe. Only a large and well-connected airport can do that, and not an enlarged Bournemouth.
I can just imagine the South American passenger stuck in Bournemouth looking for his connection to Denmark, the Baltics, or even Scotland - via a 19th century train line to Gatwick or Manston. Yep, that will reeaaly bring in the dollars to UK PLC.
Fairfrank:
The facts are simple: Heathrow needs two more runways, and it needs them yesterday, there is no getting way from it, and it will happen, probably later rather than sooner regretably.
Quite.
In other words you agree with me that we need a new Thames airport. There is absolutely no room for another two runways at LHR; and even if you destroyed much of W London to squeeze them in, you would still have the same old LHR problems. ie:
All inbounds over central London (noise, safety)
All outbounds over central London (noise, safety)
Long night curfew
Poor rail links to the rest of the country
Road congestion in the whole area
Cramped taxiway space.
Jabird:
(Silver-Foster Isle of Grain - is also much closer to established transport links).
Exactly the comparison I made yesterday between Foster's Island and Silver Island!
The population of Gravesend is around 50,000 - so if you wanted to move houses and commercial premises, I suggest a figure of £100k per head, or £5bn would be closer.
I have nothing against the Silver-Foster airport (on the Isle of Grain) being chosen in preference to the Silver-Boris Island proposal (in the estuary) - as long as it is pointing into wind; away from an over-London approach; and with sufficient runways and taxiways to accommodate the vast multitude of aircraft that will eventually use it.
But such a proposal does not come without compromises - and noise being one of them, both for Gravesend and also Southend (along with those darn newts and snails).
Ok, so Gravesend has about 12,000 homes. At £20k per household compensation, this equates to £240 million. (Your £5 bn figure is from the days of New Labour, when they thought money grew on trees. I think £20k compensation would satisfy most residents).
And please bear in mind, this is only for the revised Silver-Foster location (to keep the Foster supporters happy). The Silver-Boris Island estuary location would incur no such additional costs.
Jabird:
Looking at your island, you are also doubling the width to get these 'domestic' runways, yet wouldn't one of the aims of such a new airport be to consolidate all passengers under one very large roof - or a series of linked terminals?
If you can think of a better way, then propose it.
The problem is that aircraft taxying across runways is both time-consuming and dangerous. Thus three runways either side of a large terminal is not the optimum solution - two separate terminals linked by a rapid transit subway is more efficient.
This is doubly so, when you take customs and immigration into account. If you can separate off all the domestic/shengen traffic from the international passengers, the passenger handling is much more efficient. Likewise, if you can keep all the international transit passengers 'offshore' in one terminal, the immigration checks are again reduced.
Finally:
For the Silver-Foster concept to work, the airfield would need to be moved slightly further NW - to miss the Halstow Ridge, which conveniently runs to the SW in the same line as the take-off and approach path. But this revised location does mean even more noise nuisance for Gravesend.
.