The traditional fault redundancy process method is delayed excision, which causes degradation of flight control computer subsystem. If the residual redundancy fails again, the flight safety may be compromised. Some redundant channel faults can be restored to normal operation by restarting the redundant channel By analyzing the normal startup process of the redundancy channel and the restart process of the redundancy control application software in the flight control computer subsystem, the restart process in the dual-CPU command-monitor mode and the dual-command mode was studied. Finally, the simulation equipment node fault, flight control node fault and flight control redundancy fault were verified by experiments, and all 84 fault verification items passed the verification test.