Originally Posted by henners

And here in London we sometimes have an odd situation when there is a changeable or short term light wind.

Clearly a runway change at LHR is a royal pain, and the runways are long enough for a slight tailwind to be acceptable - so you could have operations using the 27 runways despite a modest easterly wind if it was expected to change back or drop to still before much longer.

At LCY, changing the runway in use is much easier, and the runway being much shorter having any tailwind is quite a bad idea. So, in the same situation, the airfield would always change to using runway 09.

So - you can sometimes see the planes for LCY and LHR simultaneously coming in over London...