Terry
To answer your question as to why so many KC135's it is possibly just a changing of the guard in Doha, Qatar as KC135's go and return via UK/Germany on tours of duty in the Middle East. There are usually up to 50 KC135's based in Doha at any one time and rotate regularly in batches and dependent on which USAF base they are flying and of course Atlantic weather will overfly over Scotland or Ireland.
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