briefly:
In the late 1960s, the problem of LHR being built around and limiting expansion was recognised and later ...
In 1971, the Report of the Roskill Commission on the London Airport expansion selected Cublington as the location of a proposed third airport for London on the basis of Cost Benefit Analysis. One Commission member, planner Colin Buchanan, produced a dissenting report rejecting the proposal to build on Cublington as "an environmental disaster." The government later rejected the Roskill recommendation on environmental grounds, in favour of a site at Maplin Sands, Foulness. Entry on Cublington in Wikipedia
Cublington, Maplin Sands (and sundry other locations) were all defeated by:
- NIMBY
- Environment
- The 1970s Oil Crisis
When the West had recovered from the hike in oil prices Stansted, which was already operational, was picked for expansion. LGW continued to serve it's corner of England and the leisure market. This changed later as LHR filled up and LGW became known as the 'Waiting Room'. LTN and LCY also picked up the expansion as LHR could not give space to all the short and medium haul demand. This pertains today.
The main advantage of a Hub airport is that the connection pax make certain routes viable. It might be that LHR to 'Go Jump In The Lake' would not be a viable route but, with connecting pax from various places, the route becomes viable. So the airport gains a service it would not otherwise have had. Further, a route that might have supported x3 rotations a week might now support x7 and so on.
Others will point you at the other posts, here is one thread that was active in the debate:
http://www.pprune.org/airlines-airpo...-heathrow.html
I sit to be corrected on all of the above.