As a complete aside, I once had a very interesting and unusual AR contact with a licensed amateur who was aboard a commercial flight and who was at that time a guest in the cockpit of the aircraft and who used the aircraft HF equipment to go onto the 20 metre amateur band. It was a long time ago, and obviously he had friends in high places. It would never happen today.
I've spoken to a number of Aeronautical Mobile stations, this Summer I worked an ex pat overhead Chile on his was to Dallas, he held a US and UK callsign, the latter having no provision for /AM, and there's a German chap I've spoken to a number of times who posts his flight schedule on Tw@tter so he can arrange scheds, usually 20m too
In the UK it is not illegal to own amateur equipment capable of transmiting outside the amateur bands, it's only illegal to use it in such a manner, and as far as I can recall I've never heard of amateur equipment that can transmit on VHF airband, HF only, however with the influx of Chinese tat on ebay that may not be the case any longer
