Modern strategists talk about "force multipliers," and, for air operations, air-to-air refueling is without doubt the greatest force multiplier of all. In-flight refueling has allowed not only the longest bombing missions in history but also persistence in air defense, transport reach and flexibility in ground-attack tasks. Covering a range of refuelers -- including the Boeing KC-97 and KC-135, Vickers Valiant, Handley Page Victor, Lockheed TriStar, Vickers VC10, McDonnell Douglas KC-10 and the Airbus MRTT Voyager -- this book details the history of air-to-air refueling and celebrates the key role played by tanker aircraft in the application of air power around the world.