Longitudinal aerodynamic characteristics—part 1

In the preceding chapters we have presented the general analytical foundations for solving problems concerning the motion of flight vehicles in the atmosphere. As was emphasized, however, the details of the problems and the character of the results obtained are dominated by the aerodynamic characteristics of the vehicle. It is essential therefore to explore the aero­dynamic aspect of the subject in some depth before proceeding to particular studies of vehicle dynamics. To this end, this and the following two chapters are devoted to a discussion of the main aerodynamic features of flight vehicles that are of concern for vehicle motion. Included is a body of material, traditionally referred to as “static stability and control” that relates to the control displacements and forces required to maintain steady rectilinear flight, or to maintain a steady “pull-up.” These are important items, both in relation to handling qualities and to their use as stability criteria. Clearly the spectrum of vehicle types and operating conditions of interest is extremely broad—from air-cushion vehicles and helicopters on the one hand to hyper­sonic aircraft and entry vehicles on the other. It is obviously not practical to present a comprehensive coverage of the aerodynamics of all these types within the scope of this text. The items selected for treatment are those considered to be particularly instructive and of rather broad application. With this basis it is hoped that the reader should be able to extrapolate the methods and approaches presented to other situations with which he may be
concerned. One topic completely excluded, because it requires an extensive treatment to be meaningful at all, is the aerodynamic characteristics of rotorcraft. References 6.1 to 6.4 give considerable information on this and other relevant topics in aerodynamics.