Exchange postings
In my Vulcan time (67-73 and 78-82) there were no exchange postings on the squadrons. There were, however, plenty of people who were Australians or New Zealanders, but all were members of the Royal Air Force, most of them naturalised Brits.
There was during my time always a USAF major as Chief Ground Instructor on 230 OCU. In 1967 it was Sam McClure, in 1970 Bill Heckendorm, in 1978 a major Goranewsky and, in 1979 to the end, the amazing John Harrington, with whom and with Bill Dart I once shared a snow hole for a night on Cairngorm.
I know that PN has in the past alluded to a USAF exchange officer at BCBS, but I do not recall that.