What was found
PDX - C1 - TURTLE BACK PNL AFT SPAR ATTACH FLANGE HAS FRETTING ALONG ITS ENTIRE LENGTH. REPAIRED AFT TURTLEBACK PANEL, AFT SPAR ATTACH FLANGE ALONG ENTIRE LENGTH BY BLENDING IAW RD 8/4-53-451. MEASURED THICKNESS AND FOUND LOWEST POINT TO BE .90, FOUND FLANGE TO BE WITHIN LIMITS IAW RD 8/4-53-451. HFEC INSPECTED BLENDED AREAS FOR CRACKS IAW NDTM PART 6, 51-00-01-250-801. NO CRACKS NOTED. APPLIED ALODINE AND PRIMER IAW RD 8/4-53-451. INSTALLED TEFLON TAPE IN LIEU OF FAY SEAL ALONG AFT SPAR ATTACH FLANGE IAW RD 8/4-53-451 NR 7.