ABSTRACT
Nonlinear behavior arises out of the interaction between the air and the surfaces of the projectile. It is a rather complicated mechanism that can arise (many times in a discontinuous manner) from boundary layer separation, fin masking, vortex shedding, etc. This is and continues to be a challenging area of aeroballistic research, where experimental, theoretical, and computational techniques are pushed to the limit of their usefulness. Sections 13.1 and 13.2 looks at this behavior to some degree of detail. However, because of space constraints, the reader is encouraged to consult the literature for more detailed mathematical and theoretical treatment.
