Airworthiness Directive · Amendment 39-18686 · Fuel boost pump
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 777-200, -200LR, -300, and -300ER series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 777-28-0061, Revision 2, dated May 4, 2015.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777-200, -200LR, -300, and -300ER series airplanes. This AD was prompted by a report indicating that the manufacturer discovered locations where the control components and wiring of the left and right engine fuel spar valves do not have adequate physical separation to meet the redundant system separation requirements. This AD requires modifying the wiring, and installing a new relay bracket and new location for the relay on the left and right engine fuel spar valves. This AD also requires an inspection to identify the part number of the motor operated valve (MOV) actuators for the left and right engine fuel spar valves; replacement of specified MOV actuators with new MOV actuators; certain bonding resistance measurements; and applicable corrective actions. We are issuing this AD to prevent loss of control of both the left and right engine fuel spar valves during a single event, such as local wire bundle damage or a wire bundle fire, which could cause both engines to shut down or result in the inability to control an engine fire.
Within 60 months after the effective date of this AD, modify the wiring and install new relay brackets in new locations to allow installation of new relays for the left and right engine fuel spar valves, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-28-0061, Revision 2, dated May 4, 2015, except as required by paragraph (h) of this AD.
(1) Where Boeing Special Attention Service Bulletin 777-28-0061, Revision 2, dated May 4, 2015, specifies to use Figure 22, Sheet 9, for the wiring installation of the right engine fuel spar valve, this AD requires using figure 1 to paragraph (h) of this AD.
(2) Boeing Special Attention Service Bulletin 777-28-0061, Revision 2, dated May 4, 2015, specifies to use Figure 11, Sheet 1, for the wiring change at E2-6—Shelf to Disconnect Panel and Splice Area. The figure shows the capping and stowing of an existing wire, W4255-1002-20, which is terminated at splice SP41201. The wire number is incorrect. The correct wire number to cap and stow is W6251-1002-20, which is terminated at splice SP41201.
(1) Prior to or concurrently with accomplishing the requirements of paragraph (g) of this AD: Do an inspection of the motor operated valve (MOV) actuators of the left and right engine fuel spar valves for part number (P/N) MA20A1001-1, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 777-28A0034, Revision 3, dated September 25, 2015. A review of airplane maintenance records is acceptable in lieu of this inspection if the part number can be conclusively determined from that review.
(2) If any MOV actuator having P/N MA20A1001-1 is found during the inspection required by paragraph (i)(1) of this AD, prior to or concurrently with accomplishing the requirements of paragraph (g) of this AD, replace the MOV actuator with either a new or serviceable MOV actuator having P/N MA30A1001, MA30A1017, MA20A2027, or an MOV actuator that meets the criteria specified in paragraphs (i)(2)(i) and (i)(2)(ii) of this AD; and, as applicable, measure the electrical resistance of the bond from the adapter plate to the airplane structure and, before further flight, do all applicable corrective actions. All actions specified in this paragraph for the left and right engine fuel spar valves must be done in accordance with the Accomplishment Instructions of Boeing Service Bulletin 777-28A0034, Revision 3, dated September 25, 2015.
(i) The replacement MOV actuator must be a Boeing part that is approved after the issuance of Boeing Service Bulletin 777-28A0034, Revision 3, dated September 25, 2015, by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO, to approve the part.
(ii) The replacement MOV actuator must be fully interchangeable with the part specified in Boeing Service Bulletin 777-28A0034, Revision 3, dated September 25, 2015.
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.
