As an aerospace engineer I have read many books on rotorcraft and I must admit that this is the most up to date and useful text on rotorcraft that I have had the pleasure to read. There are many aspects of the text that stand out, however the one I found most useful, especially as a graduate student, was that the equations are derived from engineering basics and are accompanied by clear explanations of the principles involved. The text and equations are also supplimented by clear diagrams that serve to enhance understanding of the more complex topics covered. All in all a great book and one that I would highly recommend to both rotorcraft students and practicing engineers alike.