Originally Posted by
Mad (Flt) Scientist
There's also an obstacle at one end I believe (the new-ish bridge at Dartford?)
The obstacle when on easterlies to runway 09 is Canary Wharf tower, about 3 miles out. There are other obstacles nearer in that come close to the resulting glide path, the old flour mill by the Victoria Dock and the somewhat elevated Connaught Bridge right at the 09 threshhold.
The obstacle when on westerlies to 27 is the Thames Gateway bridge (not the Dartford one, which is about 10 miles away). If you can't find the Thames Gateway bridge on a map you are correct, it hasn't been built yet, but the airport has to take it into account. It will be an arch bridge which will cross the Thames at the same point that you also cross the Thames on short finals for 27.