A dual-redundant flight control computer system is proposed to ensure the stability and reliability of flight. A multiplexing structure suitable for a dual-redundant flight control computer system is presented. And, minimized flight control computer was designed considering the size of the system. It is difficult to determine which one is a faulty system, unlike with triple-redundancy systems, because it has only two signal inputs. We propose using the model predictive voting algorithm to isolate the fault system in a dual-redundancy system. This algorithm consists of a built-in test, signal slope test, and analytic redundancy test. The simulation was performed by receiving the Pulse-Width Modulation obtained by the controller as an input in the same way as the real-time conditions. And, simulation is performed to analyze the performance of the voting algorithm