My understanding is the UK has a different process than everyone else for VFR flightplans. Most countries have process that says 'no news is bad news'. So if you have activated a plan (by the departure airport sending a departure message, or you calling up a service and asking for your plan to be activated), the 'system' expects an arrival message within 30 minutes of ETA and if they do not get it, over due action is commenced.
The UK operates on the system 'no news is good news', so unless the system has a reason to think there is bad news over due action will not be commenced.
If flying from an ATC field to an ATC field, during opening hours, with VFR flightplan and the arrival field has received a departure message but you don't show up, that, in all likelihood , would cause them to commence over due action.
I have never quite understood how this works for a VFR flightplan from say France to a private strip. Clearly the French won't receive an arrival message unless you call some local atsu and get them to send it (which no one seems to do) the French won't know if you have arrived. I have never heard of an issue with the French searching for planes returning to the UK so assume they must ignore unclosed plans to Brittain.
The bottom line is the UK is very different from everywhere else on this subject and a VFR plan is not particularly useful for raising the alarm (except the specific case of arriving to a field with an active ATSU). However, once the alarm is raised it does help them project you last known position to where you reasonably might have gone down.
Last edited by mm_flynn; 19th Aug 2012 at 22:02.