Aircraft equipment is operated in a wide range of external conditions, which, with a certain combination of environmental parameters, can lead to icing of the engine internal elements. Due to icing, the engine components performance characteristics change what leads to decrease in thrust, gas dynamic stability, durability, etc. Safe aircraft operation and its desired performance may be lost as a result of such external influence. Therefore, it is relevant to study the possibilities of reducing the icing effect with the help of a special engine control. The focus of this paper is to determine control methods of an aircraft gas turbine engine addressing this problem. The object of the study is a modern commercial turbofan with a bypass ratio of about 9. In this paper analysis of the effect of ice crystal icing on the engine components performance is conducted. To perform simulation of the engine performance under such impact, degraded components characteristics was introduced into physics-based turbofan model. Control algorithms for this model were developed applied to various regulated variables used in the setpoint controllers of modern engines (fan speed, engine pressure ratio, etc.). It allowed to evaluate an engine operation in ice crystal condition with each kind of controller. Additionally, the engine control method using a thrust value provided by the on-board engine model is considered. Simulation showed the ability to maintain baseline thrust with degraded engine components performance. According to calculation results, an optimal engine control method which allow compensating the negative effect of ice crystal icing is determined.