An Analytical Method To Predict Ideal H-V Boundary And C.D.P. Of Rotorcraft With Special Attention To The Application Of Optimalizing Techniques

An analytical method utilizing the optimalizing techniques to estimate the ideal height-velocity (H-V) diagram and the critical decision point (CDP) height is proposed. It is pointed out that the control inputs of pilot to the system equations describing rotorcraft dynamics are obtained as the solution of adequately stated optimalizing problem in which final rotor rpm is maximized, or equivalently, height loss is minimized or maximized. Also shown is that the degree of optimality of controls can be evaluated by means of influence functions associated with the optimal trajectories thus obtained. In order to show the applicability of this approach, sample calculations are presented for high hover point and knee point of H-V boundary, and for height loss along a partial power climb-out and rejected takeoff from CDP, while state equations which are linearized with respect to acceleration factors are used. for simplicity. A comparison with FAA flight test data as to the high hover point is included.