NASA have started to release the history of their aeronautical research as free eBooks. The Kindle, Kindle DX and Sony Readers are the only platforms listed, but the Sony Reader files are simple PDFs which can be comfortably read on virtually any machine. They are working on nook support.
The first book to be released is "X-15: Extending the Frontiers of Flight". The North American X-15 eventually reached 4,500 mph and an altitude of 67 miles (which qualifies as space flight) and this book packs a lot of techie detail, diagrams and photos about how this was achieved into its 644 pages. For example there is a detailed description of the pioneering work in computer-controlled simulators that supported the flight control development and pilot training. Digital computers were not fast enough at that time and so three EAI PACE 231R analog computers were used.
There is also a lot of fascinating information on the development of the engines, how problems with longevity and vibration were overcome to eventually reach 250,000 Newtons of thrust. It's an excellent read and I look forward to future releases from NASA.
