What was found
AIRCRAFT 9565, WHILE MAINTENANCE IN DTW WAS ACCOMPLISHING AA WORKCARD 5720-01103-01A, MTC DISCOVERED A CRACK COMMON TO THE LH WING LOWER SPAR CAP (P/N 5911301-507), COMMON TO THE LH WING REAR SPAR INSTL (P/N 9910010-511) AFT FLANGE NEAR XRS 164.000. CORRECTIVE ACTION: REPAIR STRAP TO BE INSTALLED ON AFT TANG UPPER SURFACE. FABRICATED ONE (1 QTY) TAPERED SHIM TO BE USED UNDER THE HORIZONTAL FLANGE OF THE 9957454-9 RIB CLIP. INSTALLED REPAIR PARTS AND FASTENERS PER 717 SRM 51-40-02 AND ER/A 626909-14AD. (LP 6588638)