The architecture of the autopilot control unit for the UAV is given. The possibility of using additional on-board microcomputer for collaboration with the autopilot to increase functionality of UAV is considered. The microcomputer TRIK is used. The dynamic and kinematic of flight process are described. Several coordinate systems for describe the dynamic behaviors of UAV are given. The method of partly implement the autopilot systems control modules to microcomputer is proposed. Simulation results of motion’s model in Simulink are described. Testing the proposed module on the real UAV is planned.