Wake vortices generated by an aircraft might cause severe structural dynamic response of an aircraft that encounters the wake while its strength is still high. Realistic wake-encounter cases might adversely affect the mission of the crossing aircraft or yield critical structural design loads cases. A numerical scheme for calculating the response of aeroelastic systems in such cases is presented. The new scheme is utilized in the Dynresp code for industrial dynamic loads calculations, taking advantage of its computational efficiency, feedback-loop capabilities and applicability with most general gust inputs, local aerodynamic outputs and control-system architecture. The WESDE preprocessor that calculates the wake-induced incidence angles at the aerodynamic panels in arbitrary crossing parameters is also presented. The response formulation with new gust inputs is shown to be significantly different than that of standard gust-response schemes. Frequency-domain solutions and FFT schemes are combined for an efficient, robust and adequately accurate numerical process for massive industrial applications. Propeller-engine IP load effects are included. Unsteady aerodynamic lag effects are shown to be especially important in fast wake encounter, and well represented by feedback filters that approximate Kuessner's sharp-edge gust function by rational functions in the Laplace domain. Numerical examples with a generic transport aircraft and with the A400M military transport show well-behaved a-symmetric modal solutions. Very good comparisons are shown between numerical and A400M flight-test results.
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