Two interesting helicopter books
Just read the following:
1. How the Helicopter Changed Modern Warfare by Walter J. Boyne. Author is a former USAF pilot and noted aviation historian.
2. Black Hawk: The Story of a World Class Helicopter by Ray Leoni. Author was a program manager for Black Hawk development; may be more technical than some want to know.
Both well written IMHO and highly recommended. Available at Amazon.com