Book excerpt: The remarkable Lockheed Martin U-2 high-flying spyplane celebrates its 60th birthday in 2015. But today's U-2 is a fully modernized reconnaissance aircraft, capable of serving the U.S. and its allies for many years to come. Chris Pocock has followed the Dragon Lady for 30 years. He has flown in the jet, and talked to hundreds of U-2 pilots, maintainers, managers and commanders. His previous book, "50 Years of the U-2", is the standard reference on the aircraft's history. Now he updates the story, in a richly-illustrated book with 190 charts and photos, most of them previously unpublished.