Rotor Dynamics and Helicopter Stability: Development of a Unified Mathematical Theory of the Steady and Disturbed Motion of a Helicopter with Particular Emphasis on the Dynamical Aspects of the Problem

Abstract

The purpose of the present work is to develop a unified mathematical theory of the steady and disturbed motion of a helicopter with particular emphasis on the dynamical aspects of the problem. The helicopter is assumed to undergo arbitrary small disturbances in velocity and angular velocity from a steady rectilinear flight condition, and the rotor forces are calculated as generalized functions of the initial and disturbed velocities. A high degree of accuracy is maintained both in the retention, where necessary, of products of small quantities and in the retention of high powers of µ in the solution of the trim equations. The steady motion of the helicopter is discussed at length as a preliminary to a study of its dynamic stability. Part I deals with the general features underlying helicopter motion. The importance is emphasized of a three‐dimensional approach to the problem, and it is shown that a complete description of steady rectilinear motion demands the use of fifteen equations in eighteen parameters, the solution of which presents no real difficulty. A start is made on the analysis of rotor blade motion, and the geometrical aspects are discussed by means of a system of rotating vectors.

Citation

Price, H.L. (1963), "Rotor Dynamics and Helicopter Stability: Development of a Unified Mathematical Theory of the Steady and Disturbed Motion of a Helicopter with Particular Emphasis on the Dynamical Aspects of the Problem", Aircraft Engineering and Aerospace Technology, Vol. 35 No. 3, pp. 68-72. https://doi.org/10.1108/eb033697