What was found
WING SUPPORT STRUTS (P/N C6W1005-7 LEFT, C6W1005-8 RIGHT). FOUND EXFOLIATON CORROSION ON BEAM FLANGES 12 TO 18 INCHES FROM LOWER ATTACH POINTS WHILE PERFORMING INTERNAL STRUT BEAM INSPECTION IAW FAA AD 87-04-23. SUBMITTER SUGGESTS CORROSION CAUSED BY ELECTROLYTIC ACTION OF DISSIMILAR METAL CONTACT WITH SKIN ATTACHMENT STEEL SCREWS AND PRESENCE OF MOISTURE IN STRUTS. AIRCRAFT TOTAL TIME: 28,791.3 HOURS.