This little known classic history of flight-testing the Xplanes is reborn, sweepingly revised and updated with new and recently released information. Aviation enthusiasts will savor the most detailed account available of record-setting aircraft like the X-1 and XZ-15, flown by Chuck Yeager and other legends, as well as all the cutting-edge NASA and Defense Department programs that perfected the aeronautical concepts and technology used in US military, space, and commercial craft. A completely updated and reinterpreted text, three new chapters, dozens of rare photographs, and the complete statistical record of nearly six decades of testing make this required reading for anyone interested in manned flight.