Originally Posted by
marcusnugg
As good as the idea sounds, it will be expensive, cause major disruption and take at least several years to complete. With all the additional work going on on the airfield (T5C which is nearing completion and LHR East) the project, if any, would have to wait. It would probably be much easier (and cheaper!) to build a new airport and have a system like this installed.
I think you've hit it without realizing it. Let's say BAA convinces people this is a good idea. When they mention the difficulty in upgrading the existing facilities, BAA says "you know, this would be soooo much easier if we got our third runway...."