On Sat, 16 Nov 2013 09:01:49 +0000, Roland Perry
wrote:

In message

, at 16:24:21 on Fri, 15 Nov 2013, Recliner
remarked:

Of course, they will have to stop giving "free" rides from T123 to T4 (etc)

The latter won't work, as it's a fundamental requirement for Heathrow in
the modern age to be able to move passengers from one terminal to another free of charge.

But not necessarily by underground train -- lots of airports use
inter-terminal buses, as does Heathrow for air-side movements.

Indeed, but Heathrow's layout means that using buses is extremely
inefficient and slow. It would be a major new fleet and an expensive
operation to run. Far simpler just to let the passengers use the trains,
given that the trains are already there.

Are the buses actually slower to get between T4 and T5? You'd need
two Heathrow trains to do it, and they're only 4tpi. The bus route is
fairly direct using the tunnel.