The original U-2s provided yeoman service for almost ten years before the Air Force and CIA admitted they needed to find a functional replacement that did not require a huge infusion of development funds. By 1964 the U-2L ('L' probably stood for 'long' or 'lengthened' instead of being an official designation) that Kelly Johnson had been toying with finally began to gel. Two further years of refinement resulted in the Model CL-351, and in August 1966 Lockheed was awarded a development contract. Internally, the aircraft was referred to as a U-2R for 'redesigned' or 'revised'; however the designation later became official. As near as can be determined, there were no official U-2 J-Q models. Also, the new U-2 would ultimately eliminate the practice of assigning new designations to each major modification, relying instead on a series of code words to describe the systems on each aircraft.
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