DESIGN AND DEVELOPMENT OF FLUSH AIR DATA SENSING (FADS) SYSTEM FOR WINGED ROCKET.

The primary goal of the Single-Stage-to-Orbit technology is radially to reduce the cost of access to Space. The Winged rocket developed by Kyushu Institute of Technology, Japan is the test bed and technology demonstrator for this effort. To successfully complete these missions, estimation of air data parameters are vital. FADS (Flush Air Data System) is utilized for the winged rocket. The flight control system requires indispensable air data acquisition with high precision and high reliability. However, under severe thermal environment of re-entry, the failure risk of pressure ports is high and there is as possibility that acquisition of the air data accuracy may not be reliable, which adversely affects the flight control. In this paper, the improved design of Flush Air Data Sensing (FADS) system is proposed for estimation of air data parameters for wide flight range. Wind tunnels tests have been performed for the calibration and calculating the algorithm of FADS. However, the measured and estimated values had little discrepancy in accuracy. Statistical accuracy of the calibration is evaluated by comparing the wind tunnel reference conditions to the air data parameters estimated. This comparison is accomplished by applying the calibrated FADS algorithm to the sensed wind tunnel pressures.