CORROSION DETECTION IN AGING AIRCRAFT

A CONCEPT FOR THE DETECTION OF CORROSION IN AGING AIRCRAFT USING ACOUSTIC EMISSION MONITORING IS PROPOSED. CORROSION WILL BE LOCATED THROUGH THE EFFECT THAT IT HAS ON AIRFRAME STRENGTH (10% THINNING RESULTS IN 50% FATIGUE LIFE REDUCTION). ACOUSTIC EMISSION TECHNOLOGY USED ON THE F-111 FIGHTER/BOMBER WILL BE ADAPTED FOR USE ON COMMERCIAL AIRCRAFT. PRELIMINARY CONCEPT TESTING ON A BOEING 720B HAS RESULTED IN THE DETECTION OF AN UNSUSPECTED, HIDDEN 0.5 INCHCRACK IN THE CO-PILOT'S WINDSHIELD POST, AS WELL AS THE DISCOVERY THAT CORRODED AREAS GENERATE MORE SIGNALS THAN UNCORRODED AREAS. THE END PRODUCT OF THE PHASE I RESEARCH WILL BE THE SPECIFICATION OF A METHOD FOR INSTRUMENTING, STRESSING, MONITORING AND ANALYZING AN ENTIRE AIRCRAFT USINGACOUSTIC EMISSION TO LOCATE STRUCTURAL DAMAGE CAUSED BY CORROSION.