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An analysis of a novel semianalytical method indicates that linear and nonlinear contributions are responsible for the sensitivity of the characteristic exponents of a linearized system to variations in the system parameters. Semianalytical derivatives, instead of finite difference approximations, are used to detect the linear and nonlinear contributions. Calculation of the linear contribution is possible at a low cost, but the the cost of the characteristics over which nonlinear contribution are linearized is significant.

A new sensitivity analysis method that employs a chain rule differentiation approach helps compute the sensitivities of hub loads and rotating blade root loads to variations in blade design parameters. The algorithm in the new method utilizes the features of fuselage equations of motion, blade formulations and solution technique to determine the sensitivities. Elucidation of the fuselage by nonlinear Euler equations and inclusion of nonlinearities in the mathematical model for blade yield a model that is suitable for turning and straight flight.