The effect of ice accretion was modeled on the performance and control of an aircraft. A simple method was presented to alter the aircraft stability and control parameters to model the effect of ice accretion. A six degree-of-freedom computational flight dynamics model was used to study the effect of the ice accretion on the aircraft dynamics including the effect of atmospheric turbulence and sensor noise. This study is part of a larger research program to developsmart icing system technology. The goal of the study reported here was to develop techniques to sense the effect of ice accretion on the aircraft performance and control during quasi-steady-state flight. A simple model to relate ice accretion effects to icing and flight parameters is proposed. The computational model showed large changes in V, a, and d_e as the ice accretes for a constant power and altitude case. Atmospheric turbulence and sensor noise are modeled and a filter is shown to remove most of these effects. Aircraft operated at constant velocity show smaller effects and aerodynamic sensors are proposed to aid in the characterization of these cases.