The airflow round an aircraft is a phenomenon of high complexity. To
study it, in the present state of our knowledge, demands simplifying assump-
assumptions. These must be largely based on experimental observation of what
actually happens; that is one aspect of the practical side of aerodynamics.
To make mathematical deductions and predictions belong to the theoretical
side and it is the theoretical* side with which this book is concerned.
The aim is therefore.to lay bare the assumptions, to bring them to explicit
statement so that the reader may be consciously aware of what is assumed,
and then to examine what can be deduced from the assumptions as a first
approximation.
The treatment is based on my lectures to junior members of the Royal
Corps of Na.val Constructors at the Royal Naval College during the past ten
years. ^
The mathematical equipment of the reader is presumed not to extend
beyond the elements of the differential and integral calculus. What further
is needed is mostly developed in the course of the exposition, which is thus
reasonably self-contained. It is therefore hoped that the book will provide a
solid introduction to the theory which is the indispensable basis of practical
applications.