What was found
FWD PIT, FWD CARGO DOOR CUTOUT, LOWER MAIN SILL AREA, STA 642, UPPER BEAM CHORD PLATE HAS CRACK INDICATIONS, RBL 60. [SUP 06-01-07] VERIFIED CRACK INDICATIONS PER HFEC INSPECTION. FOUND SILL CRACKED APPROX. 4.5 INCHES LONG. REMOVED LOWER DOOR SILL AND REPLACED WITH PN 451T1604-4 AND INSTALLED PER SRM 51-40-2. A/C OK FOR SERVICE. SUSPECT MULTIPLE IMPACTS FROM CARGO & LOADING EQUIP CAUSED INITIAL CRACK.