What was found
CORROSION ON SKIN AT UPPER TCAS ANTENNA AT TWO LOCATIONS BETWEEN FS295 TO FS310. ***AIRCRAFT REMOVED FROM SERVICE*** BLENDED CORROSION AT TWO LOCATIONS ON SKIN AT UPPER TCAS ANTENNA LOCATION FS295 + 4Ï¿½, RH STR 0 + 2Ï¿½, DIMENSION L = 3.00Ï¿½ X W = 2.00Ï¿½ AND FS295 + 10Ï¿½, LH STR 0 + 2Ï¿½, DIMENSION L = 3.00Ï¿½ X W = 2.00Ï¿½. ORIGINAL THICKNESS OF 0.058Ï¿½ AND MATERIAL LOSS OF 0.002Ï¿½ REMAINING THICKNESS OF 0.056Ï¿½. PERFORMED HFEC WITH NO INDICATIONS. RESTORED SURFACE FINISH. ALL WORK WITHIN LIMITS WAS PERFORMED IAW AIR WISCONSIN SUPPLEMENT NO.: 20-135A REV A, DATE OF ISSUE 5/12/2021.