| An air data system is required in all modern military and commercial aircraft. In simple terms it provides a pilot and/or flight control computers with the air vehicle orientation, airspeed, altitude, and temperature. A novel system for determining these parameters is presented in this thesis. The proposed method uses microelectromechanical system (MEMS) based flow, pressure, and temperature sensors. Advantages of this system, over current air data systems, are its ability to operate at extremely low airspeeds and the direct correlation between the flow sensors' outputs and the airspeed. Other advantages are that it is completely flush mounted, and it has low weight, size, and electrical power requirements.; This thesis describes a proof-of-concept phase for the proposed air data system. The system was tested on a flat plate and on an aircraft model in a low speed wind tunnel. The most novel element of the proposed system was the MEMS flow (anemometer) sensors. These sensors were thermally calibrated and tested in environments of variable temperature, pressure, humidity, vibration, magnetic and EMI fields, and thermal radiation. Variable air viscosity, thermal conductivity, and density were also considered. System accuracy, particle impact force, and signal frequency analyses were performed. The result of the work presented in this thesis is proof the proposed air data system could be used to provide the required air data system parameters. |
