That's the same thing like in Bagram, Kabul and some other areas. It is not a secret for many many years, because it is designed exactly to lower chances being shot with RPG. The certain radius from runway is supposed to be "clean" and carefully watched by militaries, so the only thing you need is to be out of PRG range in terms of altitude when you out of this radius. Pilots operating into and guys with RPGs around these areas know it perfectly.