What was found
THE STATION 520 FLOORBEAM WAS FOUND CRACKED AT THE FOLLOWING LOCATIONS: RBL 45, RBL 25, LBL 25 AND LBL 45. THE CRACKS ARE TYPICAL OF THOSE FOUND IN BACO S/B 737-53-1120 REV 1. THE FLOOR BEAM IS FABRICATED FROM 7075-T6511 EXTRUSION TO BAC 1518-338. NOTE: THIS A/C IS A GRP 3 A/C PER S/B 737-53-1120 REV 1. AT THREE LOCATIONS (LBL 45, LBL 25, RBL 25) THE REQUIREMENTS OF THE S/B COULD NOT BE MET IN RESPECT TO DISTANCE OF THE STOP DRILL TO THE EXISTING FASTENER HOLES. AT THOSE LOCATIONS, THE DAMAGE WILL BE TRIMMED OUT AND A DOUBLER INSTALLED.