With the rapid development of electronic technology, facing the conflict that the annual calibrating period of the test system parameters with flight test, we should prolong calibrating period、change the calibrating mode and improve the calibrating efficiency in order to better meet the demand of model test mission. This paper analyses the causes of the conflict, and proposes online calibrating and oncondition calibrating for the flight parameters test system calibration. The same time, raise a grey prediction method as the optimal management policy of calibrating period, then assesses and controls the risks. Through the optimization for the calibrating period of flight test system，prolong different test parameters calibrating period properly、shorten the test preparation cycle greatly and improve the test efficiency.