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RAF Fylingdales is under the direct command of RAF Air Command. RAF Menwith Hill is made available to the United States Visiting Force (USVF) under the terms of the NATO Status of Forces Agreement (SOFA) 1951, and other arrangements which are appropriate to the relationship that exists between the UK and the US for the purpose of our common defence. The Secretary of State for Defence retains legal possession and control over all Ministry of Defence sites, including those made available to the USVF. The bases operate with the full knowledge and consent of the Secretary of State and in full accordance with UK law.