What was found
AC RETURNED TO PLATFORM, DURING ENGINE ACCELERATION UP TO 1.4 EPR, STRONG NOISE IN THE RT ENG WAS HEARD. MAINT PERFORMED AN INSPECTION AND DETECTED ACOUSTIC LINER DELAMINATION OF THE DIFFUSER OUTER FAN DUCT, BUT WITHIN LIMITS TO OPERATE TEN HOURS IAW MM 72-00-00. AC, DURING OVERNIGHT CHECK, THE RT ENG WAS REPLACED AND TESTED IAW MM 71-00-02 AND MPCM 71-00-01, ALL CORRECT. (K)