A ans C raises an interesting point about the paint stripping qualities of Skydrol for all those who use the staff car park at LHR.
To save a walk, I always used to park near the northerly bus stop, the one the bus loiters at under the fligt path to 27R. This was until I discoverd the paint on my car blistering in small spots on the roof - I suspect from a Skydrol leak from a landing aircraft. I now park well to the south, no furhter north that the H block.