What was found
During C Check "discrepancy" as follows, #3 engine upper cowling gouged/chaffed on the #12 rib O/B section.Corrective action as follows,Cut-out damaged area on #3 engine cowl upper #12 rib I.A.W. B-727 SRM 54-10-2. Fabricated repair from 7075-T6 .050 P.O.# 9911388 size 2 3/8" X 6" I.A.W. B-727 SRM 54-10-3. Alodined and primed part I.A.W. B-727- SRM 51-10-2. Installed doubler angle I.A.W. B-727 SRM 51-30-2.1) Clean area #3 engine upper cowl on the #12 rib out of limits I.A.W. B-727 SRM 51-10-6, cut .005 area damage. Dim. 5/8" X 1/4" I.A.W. B-727 SRM 51-40-3 and 54-10-2 fig. #2.2) Fabricated repair angle Mat. 7075-T6 .050 P.O.# 9911388 size 2 3/8" X 6" I.A.W. B-727 SRM 54-10-3.3) Alodined and primed