What was found
(UT) THICKNESS MEASUREMENT WAS ACCOMPLISHED ON FLOOR STRINGERS (ATTACH POINTS) 2.9, 7.55,RBL AND BTW BS 1320 TO BS 1340 OF FLOOR STRUCTURE AT AFT CARGO COMPARTMENT, AREA IT IS OUT LIMITS PER SRM 53-00-53-1A PROCEDURE 1, DETAIL III, NOTE C (DETAIL VII); AND B757 NDT-4-51-00-10 STEP 4. FLOOR STRINGERS (ATTACH POINTS) 2.9 AND 7.55 RBL BTW BS 1320 TO BS 1340 OF FLOOR STRUCTURE AT AFT CARGO COMPARTMENT WERE REPAIRED PER B757-300 SRM. 53-00-53-2R PROCEDURE 1 REPAIR 1. (1645420) AIRCRAFT WAS GROUNDED