Thanks airac. The crux of the matter is that at present the new system would not be workable in my location. I cannot see any control measure that could be applied to a risk analysis that would ensure safety. It seems reasonable for the instrument approach traffic to expect to be separated from local IFR traffic as at present; the new system allows IFR/IMC traffic to plough through, unseparated, on a basic service. As we will only be able to separate the traffic participating in a procedural service safety will be degraded. I'm quite happy to put together a risk analysis, but I'm going to have my work cut out to come up with a control measure to make it safe, orderly and ex...etc etc.