Prediction of airplane steady spin conditions by a parameter optimization scheme

Abstract

To aid in the modeling of a steady state spin, the equations of motion of an airplane are formulated in a cylindrical coordinate reference frame. The derivation of the equations is presented and the resulting equations are simplified for the equilibrium spin condition. These simplified equations are used in an unconstrained computer parameter optimization technique that algebraically solves the differential equations for the equilibrium state. The results of the computer work are presented and compared with previous prediction schemes. The potential of the method is demonstrated by application to a study of the effects of density variation.