Peter wrote:
(GA could not exist if ATC could not deny a CAS clearance, and be able to do so without giving a reason).
I don’t think that is true. I’ve heard more than once that in the UK, ATC have to give you a reason for denying a clearance into class D – perhaps not on the radio (if they are busy there may not be time) but certainly to an enquiry later.
In the UK, they may have to file a report for a crossing refusal.
Peter wrote:
In the UK, they may have to file a report for a crossing refusal.
While this is true, and there is a CAA site to report refusals, I think that this is a completely different matter to someone taking off and not knowing what’s expected of them.
We haven’t been told exactly what happened in this case, but if someone were cleared to exit via a VRP to the south and instead turned north, or even kept going straight on while trying to fiddle with maps or GNSS navigator, potentially across the final approach or take-off segment of another runway, it could be very serious, and happen too fast for the controller to react.
Which is why it seems obvious to ask for vectors the moment you are uncertain.
Not sure that ATC would issue “vectors” to VFR traffic. What do the regulations say about that. Anybody knows?
Aviathor wrote:
Not sure that ATC would issue “vectors” to VFR traffic. What do the regulations say about that. Anybody knows?
They would suggest headings.
Dimme wrote:
Czech Republic and Germany (and a few more countries) have a special agreement.
…which, btw, is in accordance with the relevant part of SERA — SERA.4001(b)(5).
Yes, headings would be a better way to phrase it.
Airborne_Again wrote:
…which, btw, is in accordance with the relevant part of SERA — SERA.4001(b)(5).
I cannot find SERA.4001(b)(5).
I only find this:
The term ‘submit a flight plan’ refers to the action by the pilot or the operator to
provide ATS with flight plan information. The term ‘filed flight plan’ refers to the
flight plan as received and accepted by ATS whereas ‘transmit a flight plan’ refers
to the action by a pilot to submit the flight plan, or submit abbreviated flight plan
by radiotelephony to the ATS unit concerned.
which is SERA.4001(b).
Current (as of 12 October 2017) consolidated version of SERA
SECTION 4
Flight plans
SERA.4001 Submission of a flight plan
(a) ...
(b) A flight plan shall be submitted prior to operating:
(1) ...
....
(4) ...
(5) any flight across international borders, unless otherwise prescribed by the States concerned;
(6) ...
(c) ...
While I understand ATC can instruct the PIC of an aircraft on the ground at a controlled aerodrome not to take-off, can it instruct it to take-off or otherwise depart the facility (together with the aircraft under his command) ?
To provide some context, the PIC cousin of a friend’s relative’s uncle ( = perhaps me 
) , was once instructed to depart the airport to a different location when , on safety grounds, the PIC refused to accept the allocated tailwind parking position in a 30kt wind, while taxiing in after landing. Needless to say the PIC refused to accept such departure instruction, which was followed by subsequent unsuccessful and contentious enforcement action.
I have not seen any reference to such authority but would welcome illustration by the collective knowledge base herein.
This is also connected to another thread where I defended the need for light aircraft to sometimes be able to maintain heading into the wind while taxiing on the required spots, centrelines or otherwise ground-marked trajectories. That however belongs therein.
