What was found
FLAPPERS PN 3170719-2 WERE MODIFIED AS PER INSTRUCTIONS IN SB 3202222-36-1888 IAW AD 2020-16-51 IN FEB 2021, AND WERE INSTALLED ON CUSTOMERS AIRCRAFT. UNIT WAS RETURNED TO REPAIR FACILITY IN 11 MONTHS WITH SIGNS OF EXCESSIVE CORROSION IN THE SLEEVE BEARINGS. SERVICE REQUEST SENT TO BOEING FOR ANY OTHER RECOMMENDED CORRECTIVE OR PREVENTATIVE ACTION. CORROSION AROUND THE SLEEVE BEARINGS. REPLACE ALL CORRODED PARTS AND UPDATE RECOMMENDED INSPECTION, CORRECTIVE AND PREVENTATIVE ACTIONS.