Superpilot - spot on. But to take it a little further, we now need to decide what to do with the landing distance we have come up with.
Let's take a 66T A320 with GRN+YLO failure on a dry, still 26L at LGW (LDA 2831m)
By my reckoning, you need 910 x 2.8 = 2548m. Loads of room - provided you get everything absolutely spot on with the landing. But we are advised to add a factor of 15% which takes the figure up to 2930m - oops!
If you are lucky enough to have the benefit of the new FOVE, you can extract an OLD which should come out roughly the same as our increased figure.
Food for thought.
Cheers,
mcdhu