RELIABILITY CENTERED PREDICTION TECHNIQUE FOR DIAGNOSTIC MODELING ANDIMPROVEMENT

A diagnosability prediction metric is developed for system modeling of component failure rates and unjustified removals. The metric emphasiz es ambiguity of system component indications as well as system structu re. The metric is evaluated using historical data from the bleed air c ontrol system (BAGS) on the Boeing 737-300. Four design changes are su ggested bused on improving system diagnosability by changing component functions, modifying indications, and adding ol changing sensors. The resulting designs are compared via Boeing's life cycle cost mechanism , DEPCOST model, based on cost improvements. It is shown that system i mprovements based on this prediction technique will increase the quali ty of a product since increased diagnosability decreases life cycle co sts.