What was found
DETECTED COMPRESSION CRACK AT TOP OF AFT SPAR ON THE OUTBOARD END OF LIFT STRUT DOUBLER PLATE. CRACK PROGRESSED DOWN AFT SIDE ABOUT 1 INCH. LONGITUDINAL CRACK WAS ALSO FOUND IN AFT SPAR LAST 12 INCHES NEAR TIP. CRACK WAS IN CENTER OF SPAR. WHEN THE WING WAS DISASSEMBLED FOR SPAR REPLACEMENT, LONGITUDINAL CRACKS WERE FOUND ON FRONT SPAR UNDER THE DOUBLER PLATES FOR THE FUSELAGE TO WING ATTACH FITTINGS. THESE CRACKS WERE NOT DETECTED UNTIL THE PLATE WAS REMOVED. CRACKS WERE BETWEEN THE BOLT HOLES FOR THE DOUBLER PLATE. THIS WING SUSTAINED A TIP STRIKE, AND WAS REPAIRED. SUBMITTER SPECULATES THAT COMPRESSION CRACK AND OTHER DAMAGE OCCURRED AT THIS TIME.