Overun
Apologies if I misled, but thanks for picking me up on it.
What I was trying to say applies only to the UK and referred to the current perceptions of the increase in grip grooving adds to UK asphalts.
In fact your table of effects quite neatly highlights this when comparing the UK in general to the others. There are plenty of runways that have not been resurfaced recently so the half worn figures are more relevant. Stansted was done last year I recall.
I think taking your post in total it just about answers all the questions and as such should be required reading for all.
Would it be fair to say that aircraft operators seeking performance credits should in fact be looking at micro/macro texture values as opposed to whether the surface is grooved?
Sir George Cayley