But surely this issue will not go away, because most jets fly mostly on autopilot and navigation with modern kit is now so accurate that one jet could fly into the back of another one, if timed procedural separation (as over e.g. Africa) failed.
I thought someone would pick up on the converse and say that surely if these procedures are so accurate, then surely that means the noise can be concentrated in the (maybe uninhabited) other areas. Swings and roundabouts, I guess.
http://images.ibsrv.net/ibsrv/res/sr...s/embarass.gif
You are of course correct on both points: it will not go away and also, yes your other point is correct too, although it doesn't necessarily need a failure of procedural separation. See
http://www.pprune.org/rumours-news/2...er-brasil.html, GOL 737 vs Legacy over Brazil. Head-on rather than into the back of the other but you will understand my point.
I say again, though: this is all very entertaining but apart from M609's considered opinion, we don't seem to be unearthing the underlying benefits of PRNAV and how it is going to unlock capacity. I have added 'point merge' to that question now as well.
The rest of the discussion is interesting but does not really answer the question, "What's it for Mister?"