Comment from Hirotaka Takashima
Hirotaka TakashimaOtherOther
Summary: The commenter is seeking clarification on a discrepancy between the proposed Airworthiness Directive's definition of "part eligible for installation" and the service criteria provided by Woodward, Inc. regarding thrust bearing screws. They are asking for confirmation on which method of determination will take precedence once the AD becomes effective.
In this NPRM, one of the definitions of "part eligible for installation" includes the following:
(iv) A main fuel pump that has a part number identified in table 1 to paragraph (c) of this AD that has been overhauled after January 1, 2023, and confirmed to have all thrust bearing screws replaced.
There is a description following in GEnx-1B SB73-0117R1,
“Contact Woodward, Inc. (refer to the attached Woodward Service Bulletin 82933-73-0006, paragraph 2.B., Industry Support Information) to confirm if thrust bearing screws were already replaced as told in the attached Woodward Service Bulletin 82933-73-0006, paragraph 3., ACCOMPLISHMENT INSTRUCTIONS prior to the release of this Service Bulletin.”
Following this instruction, we communicated with Woodward and received the following criteria regarding the applicability of the SB:
Situation / Action
A, If overhauled before August 2022/ Needs serviced
B, If overhauled after August 2022/ No need to be serviced
C, All units overhauled at LHT or any other site than Eaton before January 2025/ Needs serviced
D, All units overhauled at LHT or any other site than Eaton after January 2025/ No need to be serviced
Therefore, there is a discrepancy between the description in the NPRM and the criteria provided by Woodward.
Is our understanding correct that, after the AD becomes effective, the applicability of the SB must be determined according to the method described in this NPRM?