What was found
MCN - MAJOR REPAIR - DURING C-16 CHECK A 3/16" CRACK WAS FOUND ON THE UPPER EDGE OF EXTERNAL SKIN AT UPPER HINGE CUTOUT OF L-1 DOOR, BS 318, STR 10 L/H; CONFIRMED BY HFEC INSPECTION. MAINTENANCE CUTOUT CRACK ON UPPER EDGE OF EXTERNAL SKIN AT UPPER HINGE CUTOUT OF L-1 DOOR; FABRICATED A REPAIR DOUBLER; INSTALLED REPAIR PART IAW B737-300 SRM 52-00-01, FIG. 203, PG. 205-206.