Failure management scheme for use in a flush air data system

This paper concerns the development of a failure management software for use in a Flush Air Data System (FADS). FADS is used for the online computation of air data parameters namely, Mach number, angle of attack and angle of side slip. Failure management, an essential requirement for FADS, especially in the context of aircraft flight control applications, has been addressed using a novel concept called failure indicator vector. This new methodology ensures the selection of correct values out of a number of redundant values of a computed air data parameter. This method leads to symbolic processing techniques, which is found to be very effective in terms of programming efficiency and simple procedure for logical reasoning. The method and the software have been successfully tested using the wind tunnel data generated at NAL.