What was found
ER/A 634632-14; A220-100, MID FUSELAGE WING TO BODY FAIRING LONGERONS BTWN FR36-38, FR42-FR45, & FR48-FR52 CORRODED. SUBJECT REPAIR REQUIRES FOLLOW-ON ACTION. ACCOMPLISH 634632-14, SECTION II REPETITIVE INSPECTION WITHIN EVERY 1,000 FLIGHT HOURS FROM 14,712 TOTAL AIRCRAFT FLIGHT HOURS AS OF 10JUN26 UNTIL SECTION III IS ACCOMPLISHED. ACCOMPLISH SECTION III PERMANENT REPAIR WITHIN 10,000 FLIGHT HOURS FROM 14,712 TOTAL FLIGHT HOURS AS OF 10JUN26. ADDITIONAL ENGINEERING AUTHORIZATION (ER/A REVISION) IS REQUIRED FOR FLIGHT BEYOND THIS LIMIT. ASSOCIATED ER/A 00-634632 ADDED FOR AC 8137. (LP# 1639775; AIRCRAFT WAS GROUNDED)