Prediction of icing effects on the lateral/directional stability and control of light airplanes

The accumulation of ice on an airplane in flight is one of the leading contributing factors to general aviation accidents, and to date only relatively sophisticated methods based on detailed empirical data and flight data exist for its analysis. This paper develops a methodology and simulation tool for a preliminary yet accurate evaluation of airplane dynamical response and stability and control characteristics due to icing. It uses only basic mass properties, configuration, and propulsion data, together with known icing data obtained for similar configurations. Existing icing data for a light airplane is suitably modified and applied to a non-real-time, six degree-of-freedom simulation model of a different but similar light airplane, developed from empirical data and Data Compendium methods. The component build-up method is used to implement icing effects on the wing alone, horizontal tail alone, and various unequal distributions of combined wing and horizontal tail icing as well as ice accretion on only one half of the wing. Results presented in the paper are limited to the roll axis and yaw axis maneuvers with various levels and distributions of ice accretion show that the methodology captures the basic detrimental effects of ice accretion on roll and yaw response and lateral stability, in addition to the sensitivity of pilot control response.