Originally Posted by
peterrabbit
Build 5D, take over T3 and extend (and improve!) the train between them and make an IAG uber-terminal between T3 and T5.
They really need to finish building T5B and C first; both were unusually truncated to save money and will be cramped once A380 services start from those terminals (not even certain B is equipped for A380 ops, which is scandalous).
Have a look how short they are compared to T5A when you're next taxiing.
T5 and T3 will eventually be essentially one terminal linked by the underground shuttle.
You'll see the toast rack plan outlined below, note that T5B and C are NOT the scale set out in the "current" scheme: