Aeroelastic analysis of twin turboprop utility aircraft

Abstract

This article deals with aeroelastic certification analyses of the new-generation Czech twin turboprop utility aircraft. The article is focused on the first phase of analyses before the ground vibration test (GVT) of the prototype. It describes the analytical model as well as the used tools and methods. The description of specific blocks of analyses follows afterwards. It includes the preliminary flutter analyses, static aeroelastic analyses (control reversal and divergence), modal analyses, and large parametric flutter analyses (surface, control surfaces, and tab flutter). The flutter characteristics of the structure with respect to changes of the selected parameters are presented. Furthermore, the preparation of the GVT (i.e. the optimization of the exciter and accelerometer positions based on the analytical results, and the whirl flutter analyses by means of an optimization-based approach to find the critical stability boundaries are explained). Finally, the performed activities are summarized and the next phase of aeroelastic certification (GVT, final analyses, and flight flutter tests) and the aircraft development are outlined.