Progress in Aeronautical Sciences, Volume 9 presents the vibrational characteristics of certain aircraft. This book supplements the comprehensive account of matrix methods of structural analysis. Organized into five chapters, this volume begins with an overview of the different schemes of the numerical method of characteristics for calculating three-dimensional steady supersonic gas flow about bodies moving at incidence. This text then examines the flow of a perfect gas and provides the generalization for the case of equilibrium and non-equilibrium flow of real gas. Other chapters consider the various aspects of the aerodynamic design of aircraft and discuss the application of modern computer methods to fluid mechanics. This book discusses as well the prospects for further development of the existing types and for the establishment of the as yet hypothetical types of aircraft. The final chapter shows how the evolution of the aerodynamic shape leads to a complete spectrum of major types of aircraft. This book is a valuable resource for engineers.