The airspace around Yeovilton is (I believe) relatively free airspace and as such a playground for ETPS @ Boscombe. I saw the AN22 recently climbing slowly out of either Liverpool or Manchester nr the Wrexham beacon and the sound she makes is very `distinctive` to the point that I was pretty certain what it was before I got a visual. The was a thread here on said machine that did help set the mindset. Perhaps the Russian Air Force have sold some hardware??