Its on another thread but I will refloat my suggestion here that there is ample land just west of LHR-a bit undualting but earthmovers can fix that. Hardly any houses and they are all owned by the same Family so only one small group to deal with Also very convenient for Legoland and a popular castle, I cannot think why no one has looked at this option before.
I also made the point that by the time UK has made its mind up all the interline trafic will have gone elsewhere, AMS,CDG,FRA and a two runway LHR will be able to handle whats left of demand anyway.
Just build a third runway but give the good peopel of Sipson a fair and attractive settlement, I doubt many are that opposed to moving but frightened that as always the Government will spend a fortune to try and cheat the people who have to move to the greatest possible degree
PB