Keygrip,
I'm confused by your claims that any airfield with a radio frequency has an ATZ. When we were flying in Florida, I can understand the logic behind using that assumption to simulate flying in the UK. After all, we were doing a UK test, and it's a close enough approximation to the UK to be able to work with.
But, as far as I'm aware, it's not actually true in the UK? I thought only licensed airfields have an ATZ? Good examples of airfields with radio frequencies but no ATZ would be Popham and North Weald - both reasonably busy, both have their own frequency, but neither is licensed, and therefore neither has an ATZ. The 1/2-million charts show all ATZs outside of controlled airspace, and it doesn't show an ATZ for either of these airfields.
For practical airmanship purposes, of course, you should give these fields a wide berth or else give them a call, and the ATZ dimensions are probably a good guideline. But I don't believe there's any legal requirement to do so.
Am I missing something?
FFF
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