What was found
DURING AN ANNUAL INSP, NOTED CRACKS IN LT AND RT WING T/E RIBS AT FORWARD END AFT SPAR ATTACHMENT POINT AREAS. AFFECTED RIBS ARE FIRST RIBS IB OF SPOILER SYSTEM ACTUATOR ATTACH POINTS. ALSO FOUND CRACKED AREA IN WING OB T/E SKIN PANEL AT ATTACHMENT POINT TO WS 118.24 T/E RIB, ALSO ADJACENT TO THE RT SPOILER AREA. AIRCRAFT HAD A MFG ELECTRIC/HYDRAULIC SPOILER SYSTEM INSTALLED PREVIOUSLY IAW STC SA4755NM. SUSPECT IN-FLIGHT STRESSES FROM NORMAL OR HIGH-SPEED OPERATIONS CAN BE CAUSING ACCELERATED FATIGUE IN THESE AREAS. RECOMMEND ROUTINE CLOSE VISUAL INSPECTION OF THESE AREAS. (K)