During the past decade and a half, several noteworthy textbooks have been published in the previously neglected field of helicopter aerodynamics, spurred no doubt by a growing acceptance worldwide of the importance of the helicopter in modern society. One may cite in this context Bramwell's Helicopter Dynamics (1976), Johnson's Helicopter Theory (1980) and Rotary wing aerodynamics (1984) by Stepniewski and Keys. The appearance now of another book on the subject requires some explanation, therefore. I have three specific reasons for writing it.

The first reason is one of brevity. Bramwell's book runs to 400 pages, that of Stepniewski and Keys to 600 and Johnson's extremely comprehensive treatment to over 1000. The users I have principally in mind are University or Polytechnic students taking a short course of lectures — say one year — in the subject, probably as an 'optional' or 'elective' in the final undergraduate or early postgraduate year. The object in that time is to provide them with a grounding while hopefully stimulating an interest which may carry them further in the subject at a later date. The amount of teaching material required for this purpose is only a fraction of that contained in the standard textbooks and a monograph of around 150 pages is more than sufficient to contain what is needed and hopefully may be produced at a price not beyond the individual student's pocket. 

J. Seddon Basic Helicopter Aerodynamics 1990