First I must clear something up. I'm not officially even a Student PPL (at the moment), though I hope to start properly in 9 months time. At the current moment I'm more concentrating on the ground school aspect and do the odd flights (maybe once a month) here and there.
Anyway, awhile ago now I was departing EGFF, VFR routing to Wenvoe VRP via the published departure. On being handed off to LARS (126.625), I was given "G-SY, hello, FIS, no altitude restriction."
I turned to my FI, and asked how high we wanted to go initially. He replied that we might aswell go up to 3500'. I immeiadetly queried this as going that high, for our current position, would have meant we'd bust the CTA by 500'. He said that we were given "no altitude restriction" and so could enter anyway. It's true that I never remeber hearing "remain clear of CAS" at any point like we normally would. And why would a controller say "no altitude restriction" when we're OCAS unless he was basically saying we could enter? It doesn't matter what they'd like to restrict us to, we're OCAS.
However. I've tried searching CAP413 to any type of reference similar to this, and there is none in the context this was used. So my questions are:
1. Is this an official procedure / standard, or is this an unofficial, mutual agreement between ATCOs and pilots?
2. If it is unofficial, and there was the extremely rare occurence that we had an AIRPROX or collision with an aircraft. Would the ATCOs take any responsibility at all for it (even though final responsibility rests with the PIC)?
3. Does this official / unofficial clearace through CAS, only hold true to CAS at an altitude? I know that most of the time they just say "no altitude restriction" when they mean any level. Yet, officially "altitude" is just that, only a reference on QNH. So I'm assuming we couldn't climb above the TA in CAS with this type of instruction. Is that correct?
We did climb up to 3500', and were Mode C Alt reporting the entire time. Not once did we get told by LARS we had bust the CTA. And as far as I'm aware my flying school never got a letter from the CAA.
