What was found
THE PASSENGER DOOR SURROUND STRUCTURE'S SILL BACKUP, MOUNTED TO STRINGER 21L, BETWEEN FS 310 AND FS 333 HAS LARGE AMOUNTS OF CORROSION. (C-CHECK RO 4/22/2021) PAX DOOR SURROUND STRUCTURE BACKUP SILL PN: SH670-31822-1, COMMON TO STRG21L LOCATED BETWEEN FS310 & FS333 IS OUT OF LIMITS OF CRJ700 SRM 53-00-00-101-001-A01, REPLACED IAW CRJ700 SRM 51-42-06-001-001-A01, CRJ700 SRM 51-42--21-001-001-A01, & DWG SH670-31810 REV Y, COMPLIED WITH TASK CARD 51-900-1002-SKY,