quotes this news item.
BBC News - Heathrow expansion won't happen, says Vince Cable
They also mention getting higher utilization out of the existing airport, but how?
I would have thought an investment in customs and immigration would be a major step. Security, obviously. Also, innovative ideas like remote baggage collection the day before departure - hubs all over the UK. Imagine not having to lug baggage. I'd pay extra for that. Furthermore, it would give more time for scanning the cases.
It's not bad as it is, given human nature, but it could flow much more . . . fluidly. That only leaves air traffic.