Does a NAA have the authority to validate licences for world wide use in aircraft on their register - generally people assume this is true, however, the argument being made is that the CAA validation is only good in the UK (or where specifically accepted).
The UK is the only place where the CAA definitely has the power to do so. Elsewhere, the local airspace owner could object.
Is the UK CAA's process of validation ineffective globally because it is automatic and does not produce a validation document. As a follow on, does this ineffective process comply with their ICAO obligation to facilitate validation of other countries licences ( recall this obligation but don't have a reference to hand).
Yes, there is such an obligation in ICAO.
More generally, does the ANO apply to G-reg aircraft extraterritorially or not. The ANO says yes, the argument implies no. (Clearly, there are lots of regulations which I will call 'Airspace Regulation' which apply to all aircraft operating in a country).
The ANO clearly
can apply outside the UK. If you have under-age sex in say Thailand (or elsewhere but I gather Thailand is a popular destination for Westerners
) then you can get done for it when you come back to the UK.
However, for example, would one expect US law or UK law to apply to the maintenance of a G-reg aircraft in the US? - and generally (and famously with a 3 engine BA 747 out of SFO) the general consensus seems to be it is the law of the country of register that applies in these airframe/licencing issues).
That seems to be the universal principle on which ICAO is built.
The State of Registry determines what privileges (if any) any given license (theirs or anybody else's) has on a plane on their register, and everybody else is supposed to respect that.
I even got exactly this from the CAA, in ~ 2003, when I asked them whether (as far as they are concerned) the IMCR is valid in an N-reg. They said they have no objection but it is up to the FAA (which is IMHO 100% correct). The FAA had no objection. Got all this in writing, too.
The other thing is that this stuff is very old and myself, or anybody I have ever spoken to, has ever heard of any problem with the above. And I am sure that if there was an issue, we would have heard of it by now. Loads of people have got FAA PPLs and are flying G-reg planes. Maybe not many on the club/rental scene but that's not suprising given the revelations in this thread... And over the years there would have been many insurance claims. And your paperwork is the first thing the insurer checks.