Flight Characteristics of Iced Aircraft

An evaluation of the effects of airframe icing on flight characteristics of fixed-wing aircraft is presented. The analysis is based on high-quality simulation models for different aircraft with distinct wing ice configurations (leading-edge and run-back ice), which are validated with flight test data and CFD results. A comparison of the distinct aerodynamic degradations leads to a general assessment of the icing influences. The icing-induced changes of the flight performance characteristics are revealed due to the interpretation of several parameters like thrust-to-weight ratio, specific excess power or lift-to-drag ratio for each ice configuration and aircraft. The change of aircraft eigenmodes is investigated by analyzing the system matrix of the linearized models at a specific trim point. Furthermore, ice-induced changes of the handling qualities are evaluated using numerical criteria of "MIL-STD-1797 A".