Don't be so quick to assume that this is a spyplane just because it is at a Russian airfield. This airport, UUS, serves the city of Yuzhno-Sakhalinsk, which has become an important destination for those in the oil and gas business. I think it is much more likely that this is a commercial passenger aircraft. There are at least four airlines, Asiana, TransAero, Aeroflot and one other whose name escapes me at the moment that fly into UUS. Two of them, Asiana and Transaero, fly western-made aircraft (Airbus and Boeing) into UUS. I know, because I have flown here several times. Visit this airport and you are quite likely to see large numbers of American and British citizens going to work for Shell, Exxon, etc.