What was found
FORWARD MAIN CABIN FLOOR SUPPORT STRUCTURE FOR DOOR BETWEEN -Y254 AND +Y254 AT FR 21 HAS CORROSION. REMOVED CORROSION IAW SRM 51-74-00, L=6 INCH, W=.5 INCH, D=.040 INCH ORIG MAT.= .055. NO ALLOWABLE DAMAGE ESTABLISHED ON SRM. REMOVED FLOOR SUPPORT PLATE IAW SRM 51-42-11 AND INSTALLED NEW SUPPORT PLATE IAW AA WORKCARD 5242-01006-01.