Abstract: As the control center of aerocraft, it is necessary to ensure the high reliability of controller design. Redundancy design is an effective way to improve the system security and mission reliability of the flight control systems. The comparison on the dualhot redundancy with the triple-hot redundancy is performed. And then, the redundancy design structure, design idea, implementation method, reliability analysis and so on are proposed. The simulations show that the performance of instrument is stable and reliable, which meet the design requirement of system reliability.