What was found
(B-18608) CORROSION WAS FOUND ON RT WING L/E FRONT SPAR LOWER ATTACH STRAP APPROXIMATE AT OSS 210. MFG TEAM PROVIDE ON-SITE TECH ASSISTANCE; SIMILAR CORROSIONS WERE ALSO REPORTED ON B-18605 AND B-18608 LT WING L/E LOWER ATTACH STRAP. ANALYSIS AND INVESTIGATION: CORRODED STRAP PN: 112A4402-4 IS MADE FROM 2324-T39 ALUMINUM PLATE. CORROSION TYPE IS IDENTIFIED AS "EXFOLIATION CORROSION", AND THIS CORROSION TYPICALLY RESULTS IN A "LEAFING" OR "DELAMINATING" EFFECT. AFTER THE OCCURRENCE OF B-18605 LT WING L/E LOWER STRAP CORROSION, IN ADDITION TO EXISTING MX INSPECTIONS, EO 738-57-20-0001 JUN. 07, 2012 WAS ISSUED TO ENHANCE THE INSP PROGRAM WITH DETAIL VISUAL INSP AT EACH AV CHECK (1-YEAR INTERVAL).