What was found
LOWER SURFACE OF LT AND RT FORWARD WING SPARS AND LIFT STRUT ATTACH FITTINGS HAVE BEEN CHAFED BECAUSE OF CONTACT WITH THE LIFT STRUT UPPER FAIRING/COVER. WORST DAMAGE WAS LESS THEN .005 INCH IN DEPTH AND WAS EASILY BLENDED OUT. APPLIED VINYL CHAFE TAPE TO SPAR AND STRUT FITTINGS TO PREVENT REOCCURRENCE. CAB02-2 REV 1 ADDRESSES THIS CONDITION BUT DOES NOT INCLUDE THIS S/N AIRPLANE. IT APPEARS THAT MFG CHANGED THE RIVET PATTERN IN THIS FAIRING/COVER ASSEMBLY, P/N 2621012-54 AND 55 ON LATER S/N AIRPLANES TO AVOID DAMAGE CAUSED BY RIVET HEADS. BUT FURTHER REDESIGN MAY BE NECESSARY TO ELIMINATE THE PROBLEM. APPLICATION OF CHAFE TAPE EFFECTIVELY PREVENTS DAMAGE. (M)