Rustle, as you say, my issue is a bit academic but I was just concerned that my meaurment of a radial differed by up to 4 deg from that as is published in the "current" Pooley and CAA maps. Needless to say I haven't gone through every one but those that I looked at differed to what was published, so I was wondering if I was missing something, i.e., could I trust myself to measure a VOR radial in the air if I was trying to pinpoint my position.
Look at the link that I posted earlier. The link is to the current CAA chart for Londonderry airport (EGAD). Dungiven is a VRP to the south east and it is also used for an instrument app. The radial is shown as R312 from BEL but if you measure it you'll find that it's actually 308. This isn't a "one off" as I've come across it in Pooleys where it gives you the position of an airfield referenced to a nearby VOR and again there's a difference of up to 4 deg for all the references, no matter what the airfield is.
