Thanks Aus ATC,
That is the point I am making. I have seen this 5mb difference regularly.
But I wonder if it has been considered in the design in the operating rules of the system?
We are told that to increase safety using GPS we can offset to the right "just in case". But we have always had level flight separation odds/evens etc..
And even with RVSM, stringent airworthiness and operations rules are applied to ensure that the high altitude "miss distance" is maintained.
It seems, unless I am missing th point, the same philosophy i.e "miss distance is not being applied in the E/C airspace area.
Perhaps it doesn't matter, after all there is also the "big sky" principle.
Regards