Airworthiness Directive · Amendment 39-21949 · Fuel controlling system
General Electric Company Turbofan Engines
This AD applies to all General Electric Company (GE) GEnx-1B64, GEnx-1B64/P1, GEnx-1B64/P2, GEnx-1B67, GEnx-1B67/P1, GEnx-1B67/P2, GEnx-1B70, GEnx-1B70/75/P1, GEnx-1B70/75/P2, GEnx-1B70/P1, GEnx-1B70/P2, GEnx-1B70C/P1, GEnx-1B70C/P2, GEnx-1B74/75/P1, GEnx-1B74/75/P2, GEnx-1B76/P2, GEnx-1B76A/P2, GEnx-2B67, GEnx-2B67B, and GEnx-2B67/P model turbofan engines with:
(1) A fuel metering unit (FMU) VIN 8062-1094 part number (P/N) 2122M20P07, VIN 8062-1176 P/N 2122M20P08, VIN 8062-1106 P/N 2459M17P01, or VIN 8062-1177 P/N 2459M17P02, installed; and
(2) An FMU having a serial number (S/N) identified in Paragraph 4, Appendix A, Table 1, of either GE GEnx-1B Service Bulletin (SB) 73-0100 R00, dated December 3, 2021 (GEnx-1B SB 73-0100), or GE GEnx-2B SB 73-0092 R00, dated December 3, 2021 (GEnx-2B SB 73-0092).
The FAA is adopting a new airworthiness directive (AD) for certain General Electric Company (GE) GEnx-1B64, -1B64/P1, -1B64/P2, - 1B67, -1B67/P1, -1B67/P2, -1B70, -1B70/75/P1, -1B70/75/P2, -1B70/P1, - 1B70/P2, -1B70C/P1, -1B70C/P2, -1B74/75/P1, -1B74/75/P2, -1B76/P2, - 1B76A/P2, GEnx-2B67, -2B67B, and -2B67/P model turbofan engines. This AD was prompted by an in-flight shutdown (IFSD) of an engine and subsequent investigation by the manufacturer that revealed an improperly torqued fuel metering unit (FMU) bypass valve (BPV) plug. This AD requires a shim check inspection of the FMU BPV plug and, depending on the results of the inspection, replacement of the FMU. The FAA is issuing this AD to address the unsafe condition on these products.
(1) Within 150 flight cycles after the effective date of this AD, perform either an on-wing or off-wing shim check inspection using a 0.005 inch feeler gauge of the FMU BPV plug to verify the FMU BPV plug is properly installed using the Accomplishment Instructions, paragraph 3.A.(4) or paragraph 3.B.(3), of GEnx-1B SB 73-0100 (for GEnx-1B models) or the Accomplishment Instructions, paragraph 3.A.(4) or paragraph 3.B.(3), of GEnx-2B SB 73-0092 (for GEnx-2B models), as applicable. Perform the shim check inspection on any flat side of the FMU BPV plug.
(2) If, during the inspection required by paragraph (g)(1) of this AD, the 0.005 inch feeler gauge can fit between the FMU BPV plug and the FMU housing on the flat side, before further flight, remove the FMU and replace with an FMU eligible for installation.
For the purpose of this AD, an “FMU eligible for installation” is:
(1) An FMU having a S/N that is not identified in Paragraph 4, Appendix A, Table 1, of GEnx-1B SB 73-0100 or GEnx-2B SB 73-0092;
(2) An FMU having a S/N identified in Paragraph 4, Appendix A, Table 1, of GEnx-1B SB 73-0100 or GEnx-2B SB 73-0092 that passes the shim check inspection required by paragraph (g)(1) of this AD; or
(3) An FMU having a S/N identified in Paragraph 4, Appendix A, Table 1, of GEnx-1B SB 73-0100 or GEnx-2B SB 73-0092 that fails the shim check inspection required by paragraph (g)(1) of this AD but has had the packing of the FMU BPV plug replaced per the Accomplishment Instructions, paragraph 3.C. of GEnx-1B 73-0100 or GEnx-2B 73-0092.
