Airworthiness Directives; Williams International, L.L.C. FJ44-1A Turbofan Engines

This amendment adopts a new airworthiness directive (AD), applicable to Williams International, L.L.C. FJ44-1A turbofan engines, that requires removing the high pressure turbine (HPT) disk from service prior to accumulating a reduced cyclic life limit of 1,900 cycles since new (CSN) and replacing with a serviceable disk. As an option, the HPT nozzle can be modified, thereby increasing the HPT disk cyclic life limit from the new reduced cyclic life limit. This amendment is prompted by a revised life analysis conducted by the manufacturer after the failure of a similarly designed HPT disk. The actions specified by this AD are intended to prevent HPT disk rim failure, which could result in an uncontained engine failure and damage to the aircraft.