Four-redundancy processing method for signal source of automatic flight control system of airplane

The invention discloses a signal source four-redundancy processing technology for an automatic flight control system of an airplane, and the technology comprises the steps: employing a self-monitoring capability of a signal source system on the basis of the conventional typical four-redundancy processing technology; carrying out the comparison and confirmation of the signal source through employing the self-redundancy of the automatic flight control system; considering and analyzing the impact on the performances of the automatic flight control system from an engineering error, and determining an engineering threshold value C; setting signal source equipment with the known stable performances for preferential use; and improving a signal screening method to select a usable signal source, thereby further improving the usability of the avionic signal source for the automatic flight control system.