What I read is that refusals of CAS transits are logged (and need to be justified), but a refusal to provide e.g. a traffic service on a CAVOK Sunday? It would be an awfully long log.
It is quite impossible to provide a watertight traffic service.
For a start, you would have to mandate Mode C (or Mode S, which includes C unless the pilot specifically disables the C) or mandate ADS-B OUT. Looking at the UK Mode S wars, that would be a fun task 
Many many people fly non-TXP or Mode A (for varying reasons, sometimes deliberately) and they make a traffic service worthless. As an extreme example, the other day I was with Wattisham, doing a flight test to FL195, and they were passing me “altitude unknown” contacts even then. Prob99 they were below 1500ft…
Then you would need to spend money on ATC desks, at about a million quid a year per H24 radar desk. I don’t even know if it could be done because there can be so much traffic that it could not be served on a single frequency, but how would you know which one of several to call up?
The best way to minimise airproxes is to fly higher, etc, as I suggested above. The slightly perverse UK PPL training works in your favour then
But then why do “everyone” fly that low?
I guess because it is more fun. I know a 3000hr homebuilt pilot who has never been above 3000ft (and cannot read tafs/metars).
It is quite impossible to provide a watertight traffic service.
Indeed and traffic information over FIS can only be provided on an as-far-as-practical basis – same all over the world.
The only way one is going to really get a better service is to file and fly IFR within controlled airspace, and be subject to CFMU slot times where need be.
Honestly I don’t bother in the UK. Last year we flew non-stop from Essex to inverness, Scotland (3.5 hours). A fair potion of the route was off the east coast of England and over the Scottish Highlands. I climbed up to 8,500 and didn’t talk to a soul until Inverness Approach. Didn’t see a single plane.
However, last year we also flew across to Wales, tracking north of Stansted and Luton at I seem to recall at ~ 4000 or 5000ft (below CAS). I thought as well we wouldn’t see any traffic up that high and we almost hit two gliders! They were everywhere; it was like a hornets nest of gliders. It scared the hell out of us and put me off flying through the central UK on a Saturday in good weather.
Eurocontrol slots are very rare, for the FL100-190 altitude range. I haven’t had one for about a year now. They used to happen mostly in the Dover area.
The biggest hurdle with Eurocontrol IFR is that you need the full IR, and a suitably capable aircraft. And practically speaking oxygen too, etc, etc. Also Eurocontrol IFR (as opposed to informal IFR in Class G) doesn’t work well within the UK for the shorter trips, because the routes can get silly – see many threads here on this topic e.g. Biggin to Jersey goes all the way over to Lydd first (with a hack involving a VFR dep from Biggin to the west, but then you are in the real traffic dodging tunnel N of Gatwick for a while, at 2400ft).
However I would not want to over-cook this issue. The moment you are out of the south east UK, traffic density plummets, and most of Europe has almost nothing, relatively speaking. Much of Europe has truly almost nothing flying.
The south east UK can be dealt with with a fairly simple strategy, as I suggested.
I keep hearing about UK pilots equipped with Mode C or S but choosing not to turn it on (I’ve never met such a pilot, though). I’ve got Mode C and it goes on at the start of every flight.
When getting basic service outside of Ronaldsway’s CAS, they’ve been pretty good at pointing out any traffic they’ve seen or know about.
It’s probably borne out of doing most of my flying hours in south east Texas where it’s hotter than hell and the altitude was required to stay out of the worst of the turbulence and heat, but I almost always fly at 3000 or above if it’s possible to do so. In fact Scottish Info actually chuckled when I called them up prior to coasting out at St Bees Head when I was at something like FL80 (I don’t think they are used to fabric taildraggers being up that high). Unfortunately I’m not very good at thinking up witty retorts on the fly (something about being afraid of water would have probably been the one).
I understand all of the above and agree – mostly. However would it not be far more appropriate to simply say there is no radar service available, do not give a discrete squawk and let the flying community then be certain that they are entirely responsible for their own separation etc. OCAS. Instead we have this entirely stupid system in the UK of “pretence”!!!!
I understand all of the above and agree – mostly. However would it not be far more appropriate to simply say there is no radar service available, do not give a discrete squawk and let the flying community then be certain that they are entirely responsible for their own separation etc. OCAS. Instead we have this entirely stupid system in the UK of “pretence”!!!!
Yep, understand you’re sentiment. For me, its a case of make the best of it when you can, or get an IR or EIR. I have an IMCr (IR and it will be interesting to see if I do the EIR whether suddenly all the doors open to CAS, and I get a pleasant flight to wherever with a radar service all the way. The reality is probably not, and by the time it comes round it will probably be back to icing conditions / stay away from clouds season :-(
I think possibly the biggest thing in all this is that no matter how much technology or money you throw at it, and no matter how many “Mk 1 eyeballs” (the UK Royal Air Force term) you have in the cockpit looking out, something like 90% of traffic will never be seen. And with a radar service, that might go down to perhaps 50%.
You don’t need too much in the way of technology to realise this. A few flights in a TCAS equipped plane will do the job nicely 
And that shows only the transponding ones! The rest you can’t see, except you glimpse a bit of it visually here and there
All that is totally contrary to what everybody tells you in PPL training.
