What was found
CREW PREFLIGHT INSPECTION FOUND ONE RIVET HEAD BROKEN OFF IN FUSELAGE SKIN, LEFT HAND SIDE, FRAME NR 9, JUST BELOW CAPTAIN'S DV WINDOW. FURTHER INVESTIGATION REVEALED A CRACKED SKIN SUPPORT AT THAT LOCATION. THE SUPPORT WAS REPLACED PER AERODESIGN REPORT NR 660-1, IR, 2-16-93. AIRCRAFT RETURNED TO SERVICE.