Airworthiness Directive · Amendment 39-17323 · CFM International, S.A. Turbofan Engines Modified by Supplemental Type Certificate SE00034EN
CFM International, S.A. Turbofan Engines Modified by Supplemental Type Certificate SE00034EN
Superseded. A later AD replaced this one: AD 2016-14-10. Comply with the one in force.
This AD applies to CFM International, S.A. CFM56-3, CFM56-3B, and CFM56-3C turbofan engines, modified by Supplemental Type Certificate SE00034EN, with a high-pressure turbine (HPT) disk, part number (P/N) 880026, serial number (S/N) GLKBAA9307, GLKBAA9335, GLKBAA9404, GLKBAA9407, or GLKBAA9409, installed.
We are adopting a new airworthiness directive (AD) for CFM International, S.A. CFM56-3, CFM56-3B, and CFM56-3C turbofan engines. This AD requires removal from service of certain high-pressure turbine (HPT) disks manufactured by Global Material Solutions of Pratt & Whitney, at reduced maximum life limits. This AD was prompted by a report of a forging process error during manufacture of these HPT disks. We are issuing this AD to prevent uncontained release of multiple turbine blades, damage to the engine, and damage to the airplane.
(1) For CFM56-3, CFM56-3B, and CFM56-3C turbofan engines operating to 20,100 lbs maximum takeoff (MTO) thrust, remove the HPT disk from service on or before accumulating 8,000 cycles-since-new (CSN).
(2) For CFM56-3B and CFM56-3C turbofan engines operating to 22,100 lbs MTO thrust, remove the HPT disk from service on or before accumulating 8,000 CSN.
(3) For CFM56-3C turbofan engines operating to 23,500 lbs MTO thrust, remove the HPT disk from service on or before accumulating 4,000 CSN.
(4) For HPT disks that have been used in multiple models or thrust installations, the formula in the ADDED DATA section of Pratt & Whitney Special Instruction 6F-12 dated December 21, 2012 must be used to calculate the remaining life on the disk.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
