**Title:-
Flight
Dynamics**

**Author:- **Robert F. Stengel

**Publisher:-** Princeton
University Press

**Publication
date:-** 2004

**ISBN:- ** 0-691-11407-2

**Retail
Price:-** $99.50
(£65.00)

**Reviewer:-** M.V.Cook,
School of Engineering, Cranfield University.

The eminence of Professor Robert Stengel will be well known
to most engineers, scientists and academics working in the field of flight
dynamics. His universally acknowledged position as a leading academic in the
field derives from his Òreal worldÓ experience which includes involvement in
the design of the Apollo Lunar Module and the direction of many flight
experiments in the modified Navion light aircraft at Princeton. Over a period
of many years the results of his research have been published in countless
papers. Since he is an undisputed authority in the field of flight dynamics it
came as no surprise to learn that he has published a new book on the subject and
an opportunity to review this text was eagerly awaited.

First impressions were that this is a substantial book (845
pages) and that it is extremely well researched, having a very large number of
references and a useful bibliography of NASA reports related to aircraft
configuration aerodynamics. The content of the book is a little unusual in that
it really is totally focused on the topics we understand to comprise modern
Flight Dynamics, the author having resisted the temptation to stray into the
closely related field of flight control. However, flight control system topics
are included appropriately where it is relevant to do so. It is pleasing to see
that the subject treatment is securely founded on aerodynamics and flight
physics, and that subsequent topic development makes extensive use of the
mathematics and tools of modern systems analysis. This, of course, is entirely
consistent with the computer age in which we now live and work and it helps to
make the material readily accessible.

The style of the book also differs a little from the norm.
It reflects the unmistakable enthusiasm of the author for the subject, his
considerable application experience and his ability to make the most complex
topic easy to assimilate – a skill no doubt refined over many years of
teaching students. His approach is to take each topic, to reduce to its most
basic foundations and then to develop it step by step until the desired
objective is reached. This means, for example, that the reader is taken through
a mathematical development from its most elementary starting point. In
comparison, most authors of similar texts omit the most basic steps on the
basis that it is assumed prior knowledge. The dangers of this approach in a
teaching context are well known. Consequently, it seems at first sight that
some of the material in the book is pedantically comprehensive. However, this
opinion is short lived when it is appreciated just how accessible the material
becomes as a result of this approach. The style must therefore greatly enhance
the book as a learning resource for students and it also makes it an especially
valuable reference for those already familiar with the subject area. This
reviewer found the book so useful in this respect that the review process was
temporarily overlooked!

In spite of its considerable volume, the book has only
seven main chapters, which reflects the thorough and comprehensive treatment of
the material. The introductory material reviews a variety of modern aircraft
ÒshapesÓ and comments very briefly on their principal characteristics in
context. No doubt with the student in mind, the introduction concludes with a
Matlab example showing how the flight mechanics of a simple paper aeroplane can
be modelled and evaluated. The second chapter is called *Exploring the flight
envelope*, and serves to
introduce all the foundation flight mechanics. This covers atmosphere physics,
axes systems, kinematics, aerodynamics, powerplants and performance. The
objective here is to assemble the basic mathematical models on which all flight
dynamics depends. The third chapter, *Dynamics of aircraft motion*, builds an extremely complete mathematical
model of the aircraft with reference to both linear and non-linear solutions. A
substantial part of this chapter includes an in-depth discussion of the
aerodynamic contributions to the equations of motion. Chapter four deals with *Methods
of analysis and design*, and
unusually it deals with both the familiar and the less familiar. Topics include
linearization, solution of linear differential equations, stability, time and
frequency domain analysis, parameter uncertainty, aeroelasticity and flying
qualities and flight control. Chapters five and six deal with *Longitudinal
motions* and *Lateral-directional
motions* respectively. The
approach is similar in both chapters and most of the topics are familiar.
However, the depth of the analytical discussion is considerably greater than is
usual in books on the subject and the detail affords a powerful insight into
aircraft dynamics. Chapter seven deals with *Coupled longitudinal and lateral-directional
motions*. Topics include small
amplitude motions, inertial coupling, ÒsystemsÓ exhibiting dynamic bifurcation
and some of the most recent advances relating to flight at very high angles of
attack.

Clearly, the book has been written with the student market
in mind as it includes many worked examples to illustrate application of the
material. Further, much of the example material is structured around a suite of
Matlab programs which are available from the author and I am sure that the interest
in this material will extend well beyond the student market. Summaries of the
software tools and tutorial example aircraft models are given in the
appendices. However, the reader can download the programs from the authorsÕ web
site - http://www.pupress.princeton.edu/stengel.

This is a terrific book which should appeal to students and
practitioners alike. It is most comprehensive, thorough in its detail and the
style of writing makes the subject easily accessible to all. Students and
teachers will find in it a resource that is complete and compatible with the
requirements of the industry and research organisations. Practising engineers
and researchers will find the book an invaluable reference, especially as it is
comprehensive and starts from first principles which makes it easier to deal
with unconventional configurations. All that is required of the reader is a
reasonable graduate level ability in engineering mathematics, but such is the
thoroughness of the treatment that much of the mathematics is explained as
well. I recommend this book without hesitation to those engaged in, or aspiring
to become engaged in, flight dynamics, flight test, flight control and related
flight sciences. Priced at £65 it represents very good value for money, and for
that it is hardbound as well!