Abstract: A flush air data sensing (FADS) system was designed to measure the aerosphere parameters at the launch vehicle fairing. The measurement plan and precision were investigated for the launch vehicle FADS. Wind tunnel test was used to demarcate the measurement error and shape-pressure coefficient. The results show that the FADS has good reliability and precision to identify the aerosphere parameters at Mach number of 0.4~5.0. Both errors of the angle of attack and the angle of sideslip are less than 0.5°, the error of Mach number is less than 0.1, the error of the static pressure is less than 5%. The FADS system can be universally applied to the flight control, wind correction and load control of the launch vehicle.