For the pilot-aircraft system with pilot model concerning human factors, traditional control methods on specific models cannot totally satisfy flight trajectory precision.An unfalsified PI controller design method based on fading memory and linearly increasing cost level algorithm is introduced for such pilot-in-loop system.Unfalsified adaptive control theory is a non-model data-driven control theory, which only uses model input and output data.In the unfalsified control theory, the supervisor selects the best controller and the controller switching algorithm switches controllers when necessary.Fading memory method decreases the impact on switching algorithm which is caused by old data.Monte Carlo simulation is made in designed flight scenario.The result indicates that the designed controller improves the flight performance.