Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2023-1805; Project Identifier AD-2023-00019-T; Amendment 39-22695; AD 2024-05-04]</DEPDOC> <RIN>RIN 2120-AA64</RIN> <SUBJECT>Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Federal Aviation Administration (FAA), DOT. <HD SOURCE="HED">ACTION:</HD> Final rule. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The FAA is superseding Airworthiness Directive (AD) 2020-23-04, which applied to certain Gulfstream Aerospace Corporation Model GVII-G500 and GVII-G600 airplanes. AD 2020-23-04 required revising the existing airplane flight manual (AFM) and airplane maintenance manual (AMM) to include information pertaining to the fuel boost pump. This AD was prompted by a report of misassembled impellers on the shaft of the fuel boost pump during production. This AD retains the requirements of AD 2020-23-04 and requires inspecting affected fuel boost pumps for proper installation of the impeller shaft key, marking affected fuel boost pumps that pass that inspection, and replacing fuel boost pumps that fail. This AD also limits the installation of affected fuel boost pumps. The FAA is issuing this AD to address the unsafe condition on these products. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This AD is effective May 2, 2024. The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of May 2, 2024. The Director of the Federal Register approved the incorporation by reference of certain other publications listed in this AD as of November 24, 2020 (85 FR 71232, November 9, 2020). </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> <E T="03">AD Docket:</E> You may examine the AD docket at <E T="03">regulations.gov</E> under Docket No. FAA-2023-1805; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. <E T="03">Material Incorporated by Reference:</E> • For service information identified in this final rule, contact Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA 31402-2206; telephone 800-810-4853; email <E T="03">pubs@gulfstream.com;</E> website <E T="03">gulfstream.com/en/customer-support</E> . • You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available at <E T="03">regulations.gov</E> under Docket No. FAA-2023-1805. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Jared Meyer, Aviation Safety Engineer, FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: 404-474-5534; email: <E T="03">9-ASO-ATLACO-ADs@faa.gov</E> . </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Background</HD> The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2020-23-04, Amendment 39-21320 (85 FR 71232, November 9, 2020) (AD 2020-23-04). AD 2020-23-04 applied to certain Gulfstream Aerospace Corporation Model GVII-G500 and GVII-G600 airplanes. The NPRM published in the <E T="04">Federal Register</E> on September 5, 2023 (88 FR 60606). The NPRM was prompted by a report of misassembled impellers on the shaft of the fuel boost pump during production. In the NPRM, the FAA proposed to continue to require revising the existing AFM and AMM to include information pertaining to the fuel boost pump. The NPRM also proposed to require inspecting affected fuel boost pumps for proper installation of the impeller shaft key, marking affected fuel boost pumps that pass that inspection, and replacing fuel boost pumps that fail. The NPRM also proposed to limit installation of affected fuel boost pumps. The FAA is issuing this AD to prevent the ignition of flammable vapors in the fuel tank as a result of frictional heating or sparks caused by a missing, misplaced, or dislodged impeller shaft key inside the fuel boost pump. The unsafe condition, if not addressed, could result in a potential source of ignition in the fuel tank and consequent fire or explosion. <HD SOURCE="HD1">Discussion of Final Airworthiness Directive</HD> <HD SOURCE="HD1">Comments</HD> The FAA received a comment from an anonymous commenter who supported the NPRM without change. The FAA received additional comments from Gulfstream Aerospace Corporation (Gulfstream). The following presents the comments received on the NPRM and the FAA's response to each comment. <HD SOURCE="HD1">Request To Change the Maintenance Manual Version</HD> Gulfstream requested that the FAA change the maintenance manual revision dates specified in paragraph (g) of the proposed AD to refer to subsequent dates. Gulfstream stated that GVII-G600 Maintenance Manual 28-26-04 Fuel Boost Pump-Removal/Installation Procedure, dated August 31, 2020, was revised March 31, 2023, to include non-technical changes (including the use of puller tool to reduce risk of damage to Fuel Boost Pump (FBP) during removal with a caution note to avoid excess force when removing FBP and a step to record FBP serial number to determine serviceability). Gulfstream also stated that GVII-G500 Maintenance Manual 12-13-01 Defueling Procedure-Defuel, dated August 31, 2020, and GVII-G600 Maintenance Manual 12-13-01 Defueling Procedure-Defuel, dated August 31, 2020, were revised on September 30, 2023, due to an administrative error. The FAA agrees with the request. The revised defueling procedure requested by Gulfstream is acceptable because it instructs fuel boost pump maintenance to be performed in a way that addresses the unsafe condition and it prevents damage to the parts being removed/installed. The FAA has revised paragraphs (g)(1)(i), (ii), (iii), and (v) of this AD accordingly. <HD SOURCE="HD1">Request To Change Paragraph (i) of the Proposed AD</HD> Gulfstream requested that the compliance time in paragraph (i) of the proposed AD be revised from “replacing the pump before further flight” to “replacing the pump following the completion of the CB [customer bulletin] before further flight.” Gulfstream reported the statement “this AD requires replacing the pump before further flight in accordance with the requirements of paragraph (h) of this AD” in paragraph (i) of the proposed AD could be misleading. Gulfstream stated it believes this statement could be misunderstood by operators to mean that the AD immediately grounds their aircraft. The FAA agrees with the commenter that paragraph (i) of this AD should be revised to clarify the intent of this AD. Operators have 24 months to comply with all applicable actions required by paragraph (h) of this AD. The FAA has revised paragraph (i) of this AD by removing the reference to “before further flight” and specifying that where the service information says to return a pump, this AD requires that the pump must be replaced. <HD SOURCE="HD1">Request for Removing GVII-G500 AFM</HD> Gulfstream requested removing reference to “Gulfstream Aerospace GVII-G500 Airplane Flight Manual Supplement No. GVII-G500-2020-06, dated September 8, 2020,” from paragraph (g)(2)(ii) of the proposed AD; Gulfstream stated there are no GVII-G500 airplanes in this configuration, all aircraft have been updated to GVII Block 1 software configuration, therefore this reference to the airplane flight manual supplement is not applicable. The FAA has confirmed with Gulfstream that Gulfstream Aerospace GVII-G500 Airplane Flight Manual Supplement No. GVII-G500-2020-06, dated September 8, 2020, is no longer applicable to the existing fleet. However, Gulfstream Aerospace GVII-G500 Airplane Flight Manual Supplement No. GVII-G500-2020-06, dated September 8, 2020, is retained in this AD. Operators may have previously complied with paragraph (g)(2)(ii) of AD 2020-23-04 using GVII-G500 Airplane Flight Manual Supplement No. GVII-G500-2020-06, dated September 8, 2020. Therefore, to provide credit to operators who have already complied with the service information and reduce the need for alternative method of compliance (AMOC) requests, the FAA has determined that this AD should include reference to GVII-G500 Airplane Flight Manual Supplement No. GVII-G500-2020-06, dated September 8, 2020. No changes have been made to this AD in this regard. <HD SOURCE="HD1">Conclusion</HD> The FAA reviewed the relevant data, considered any comments received, and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for minor editorial changes, and any other changes described previously, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator. <HD SOURCE="HD1">Related Service Information Under 1 CFR Part 51</HD> The FAA reviewed Gulfstream GVII-G500 Customer Bulletin No. 069 and Gulfstream GVII-G600 Customer Bulletin No. 037, both Revision A, both dated February 2, 2023. This service information specifies procedures for inspecting affected fuel boost pumps for proper installation of the impeller shaft key, marking affected fuel boost pumps that pass that inspection, and replacing fuel boost pumps that fail. These documents are distinct since they apply to different airplane models. The FAA also reviewed the following AMM documents, which contain revised maintenance procedures pertaining to the fuel b ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 31k characters. 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