Airworthiness Directive · Amendment 39-22411 · Fuel
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 747-400 and 747-8 series airplanes, certificated in any category, equipped with an activated horizontal stabilizer fuel tank with Crane Aerospace Hydro-Aire horizontal stabilizer fuel transfer pump housings and transfer pump motor impellers.
The FAA is superseding Airworthiness Directive (AD) 2022-27- 07, which applied to certain The Boeing Company Model 747-400 and 747-8 series airplanes. AD 2022-27-07 required inspecting for wear of the transfer pump housing inlet check valves and transfer pump motor impeller inlet adapters for the horizontal stabilizer fuel tank and doing corrective actions, if necessary. This AD was prompted by the discovery that certain airplanes were incorrectly included in the applicability of AD 2022-27-07. This AD continues to require inspecting for wear of the transfer pump housing inlet check valves and transfer pump motor impeller inlet adapters for the horizontal stabilizer fuel tank and doing corrective actions, if necessary. This AD also removes certain airplanes from the applicability, redefines the definition of an "activated" horizontal stabilizer fuel tank, and limits the installation of affected parts. The FAA is issuing this AD to address the unsafe condition on these products.
This paragraph restates the definitions specified in paragraphs (g)(1) and (2) of AD 2022-27-07, with a revised definition.
(1) A “serviceable” transfer pump motor impeller inlet adapter is an inlet adapter of the motor impeller assembly for which any missing material does not exceed 0.20 inch in the pump axial direction.
(2) A “serviceable” transfer pump housing inlet check valve is an inlet check valve for which the hinge pin protrudes past the flapper arm on both sides and there is no metal disk gouging, missing material, corrosion, burrs, or raised material. Minor surface scratches, defects, or appearances of surface wear are acceptable.
(3) A horizontal stabilizer tank is considered to be “activated” if it is not deactivated in production or deactivated by an approved alteration.
This paragraph restates the requirements of paragraph (h) of AD 2022-27-07, with no changes. Within 90 days after January 13, 2023 (the effective date of AD 2022-27-07): Do a detailed visual inspection of the transfer pump housing inlet check valve in the left and right transfer pump housing for hinge pin protrusion, gouging, missing material, corrosion, burrs, and raised material, in accordance with paragraph C., Work Instructions, Attachment A, Boeing Multiple Operator Message MOM-MOM-22-0549-01B(R1), dated November 29, 2022.
(1) Condition 1: If the hinge pin does not protrude past the flapper arm on one side, or if any gouging, missing material, corrosion, burrs, or raised material is found on the transfer pump housing inlet check valve, do the actions required by paragraphs (h)(1)(i) and (ii) of this AD.
(i) Report inspection findings in accordance with paragraph (j) of this AD.
(ii) Prior to further flight, replace the transfer pump housing inlet check valve or transfer pump housing with a serviceable transfer pump housing inlet check valve or transfer pump housing containing a serviceable transfer pump housing inlet check valve, in accordance with paragraph C., Work Instructions, Attachment A, Boeing Multiple Operator Message MOM-MOM-22-0549-01B(R1), dated November 29, 2022.
(2) Condition 2: If the hinge pin does protrude past the flapper arm on both sides, and no gouging, missing material, corrosion, burrs, or raised material is found, report inspection findings in accordance with paragraph (j) of this AD.
This paragraph restates the requirements of paragraph (i) of AD 2022-27-07, with no changes. Within 90 days after January 13, 2023 (the effective date of AD 2022-27-07): Do a detailed visual inspection of the transfer pump motor impeller inlet adapter for wear (missing material), in accordance with paragraph D., Work Instructions, Attachment A, Boeing Multiple Operator Message MOM-MOM-22-0549-01B(R1), dated November 29, 2022.
(1) Condition 1: If any wear is found that is 0.20 inch or less, report inspection findings in accordance with paragraph (j) of this AD.
(2) Condition 2: If any wear is found that is greater than 0.20 inch, do the actions required by paragraphs (i)(2)(i) and (ii) of this AD.
(i) Report inspection findings in accordance with paragraph (j) of this AD.
(ii) Before further flight, replace the transfer pump motor impeller with a transfer pump motor impeller having a serviceable inlet adapter, in accordance with paragraph D., Work Instructions, Attachment A, Boeing Multiple Operator Message MOM-MOM-22-0549-01B(R1), dated November 29, 2022.
This paragraph restates the requirements of paragraph (j) of AD 2022-27-07, with no changes. At the applicable time specified in paragraph (j)(1) or (2) of this AD, submit a report of all findings of the inspections required by paragraphs (h) and (i) of this AD, in accordance with paragraph G. and Appendix A, Attachment A, Boeing Multiple Operator Message MOM-MOM-22-0549-01B(R1), dated November 29, 2022.
(1) If the inspection was done on or after January 13, 2023 (the effective date of AD 2022-27-07): Submit the report within 30 days after the inspection.
(2) If the inspection was done before January 13, 2023 (the effective date of AD 2022-27-07): Submit the report within 30 days after January 13, 2023.
This paragraph restates the requirements of paragraph (k) of AD 2022-27-07, with revised affected parts. As of January 13, 2023 (the effective date of AD 2022-27-07), no person may install, on any airplane, a Crane Aerospace Hydro-Aire horizontal stabilizer fuel transfer pump housing or transfer pump motor impeller, unless the transfer pump motor impeller inlet adaptor and transfer pump housing inlet check valve have been inspected as specified in paragraph (h) or (i) of this AD, as applicable, and been determined to be a serviceable part as defined in paragraph (g)(1) or (2) of this AD.
This paragraph restates the provisions of paragraph (l) of AD 2022-27-07, with no changes. This paragraph provides credit for actions required by paragraphs (h) and (i) of this AD, if those actions were performed before January 13, 2023 (the effective date of AD 2022-27-07) using Boeing Multiple Operator Message MOM-MOM-22-0549-01B, dated November 21, 2022.
