What was found
MAIN CABIN FLOOR BEAM AT STA. 947.5 LBL24 IS CORRODED. GROUNDED - YES. REMOVED DAMAGE & CHECKED LIMITS ORI MAT .180,REMOVED MAT .050,REMAINING MAT .130 FOUND TO BE OUT OF LIMITS. CUT OUT UPPER CHORD OF THE FLOOR BEAM STA 947.5 FROM RBL51 TO LBL51.FABRICATED,LOCATED DRILLED AND INSTALLED REPAIR PARTS T-CHORD,2EA ANGLES AND 2EA STRAPS,10EA FILLERS IAW B737-900ER SRM 53-70-51-2R-5 REPAIR 5 ALTERNATIVE 1,SRM 53-70-51-1A-1.