frb, some thoughts for you, yes its possible, though highly unlikely, make sure they will pay you before you go overboard for them!. Firstly if it were that easy it would have been done by now or would be being considered! Recent looks by various men in suits have looked at Heathrow, runway to north, Gatwick, runway to north west, and Stansted runway to South East.
Location:
Assuming its in the Wisley area, this would tie in with your general description. Yes there was an airfield there, even bits of it left as far as I know, check the aerial picture on multimap.com for recent status. It would have approx 2000m-2500m of runway, that would work for B737's/75's and I expect most minibi for shorthaul and certainly as far as greece, maybe Canaries, in term of range for those types, with no significant performance penalties. Assuming this space is found you have to persuade south west/west london that another airport on their doorstep is a good idea!. Next you need ground communications, all above airports obviously have those extant. Most people travel to airports by car, therefore you are looking to place a significant amount of traffic into the M40-M3 quadrant of the M25, already the worst congested area of the M25. Also for a punter, why drive past heathrow from the north/west and gatwick from the south/east to get to an airport in between them?
Rail connections, poor from north, east and south, as the area is on the south western and western rail links to london, neither of which currently connect well enough for fast links to this general area.
ATC: I will assume its Wisley for this. Most airports in the south east have a bias of 70% westerly operations per annum. So using your westerly runway, and LHR/LGW using theirs:
Northbound departures clash with heathrow northerly, westerly, southern departures, as they will have to cross the heathrow departure routes. In very broad terms uk northerly traffic flies east of the M1, and southerly flies west of the M1, therfore you need to go to Brecon before you can agin head north!. Your southerly/westerly departures will cross LGW northbounds. Whilst speaking in very simple terms bear in mind the current traffic levels, your project assuming greenfield site, will be a minimum of 5 years away so air traffic growth etc etc..... Easterly departures will have similar clashes in reverse, not to mention if your northbound, going round or over London and the conflicting traffic filtering onto the LHR approach if they are still on westerlies!. Swanick will probably have the capacity, but it would be the local co-ordination of traffic so close to LHR and LGW that would give real problems.
Noise: define significant conurbation! Many noise complaints come from well over 5 miles from an airport!. You will be looking at big trouble here, you have to look at the big picture: noise, air quality, water etc in an already sensitive area, we have only just had the T5 enquiry that took 5 years I think, just for a terminal, think how long a new airfield will take!. Whilst having used Wisley as the centre for these comments much the same can be made for the M40/M3 area. To make this work from start up and to return investors outlay I feel is unrealistic, to give you an idea it sounds like you would be looking at trying to place todays Luton airport in that location. Environmentally and in practical terms the argument would be to displace 'your' traffic to the existing airports, in the region, long before any serious consideration would be given to a new airport in that general area. Also Redhill, just north of LGW was considered for a feeder airport for LGW and LHR a couple of years back, that was given a big thumbs down on both ATC and environmental issues if memory serves me correctly.
Hope the above is food for thought that'll be 25 quid please!
