Airworthiness Directive · Amendment 39-18414 · Fuel
The Boeing Company Airplanes
This AD applies to all The Boeing Company airplanes identified in paragraphs (c)(1) through (c)(4) of this AD, certificated in any category.
(1) Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes.
(2) Model 757-200, -200PF, -200CB, and -300 series airplanes.
(3) Model 767-200, -300, -300F, and -400ER series airplanes.
(4) Model 777-200, -200LR, -300, -300ER, and -777F series airplanes.
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, Model 757 airplanes, Model 767 airplanes, and Model 777 airplanes. This AD results from fuel system reviews conducted by the manufacturer. This AD requires an inspection to determine if certain motor-operated valve (MOV) actuators for the fuel valves are installed, and replacement of any affected actuators. Previous ADs addressed this Special Federal Aviation Regulation No. 88 (SFAR 88) issue for the majority of the airplanes delivered with these actuators. Since those ADs did not cover all of the airplanes, and for some airplanes delivered with improved actuators, there was no restriction on installation of replacement actuators with the unsafe condition, this additional rulemaking action is required. As with the related ADs, we are issuing this AD to prevent electrical energy from lightning, hot shorts, or fault current from entering the fuel tank through the fuel valve actuator shaft, which could result in fuel tank explosions and consequent loss of the airplane.
For Model 767-300 series airplanes having line numbers 939 and 940; and Model 777-200, -200LR, -300, -300ER, and -777F series airplanes, except airplanes having line numbers 454 through 551 inclusive, and 563 and subsequent: Within 60 months after the effective date of this AD, do an inspection to determine whether any motor-operated shutoff valve (MOV) actuators having P/N MA20A1001-1 (S343T003-39) for the fuel tanks or fuel feed system are installed on the airplane. A review of airplane maintenance records is acceptable in lieu of this inspection if the part number of the actuator at each location can be conclusively determined from that review.
(1) For Model 767 airplanes, there are several affected actuator locations: the fuel shutoff valves, the fuel crossfeed valves, the defueling valves, the jettison nozzle valves, the jettison transfer valves, the auxiliary power unit (APU) fuel shutoff valve and the APU fuel isolation valve.
(2) For Model 777 airplanes, there are several affected actuator locations: the fuel shutoff valves, the fuel crossfeed valves, the defueling valves, the jettison nozzle valves, the jettison isolation valves, the APU fuel shutoff valve, the APU fuel isolation valve, the auxiliary tank isolation valve, the auxiliary tank refuel valve, the auxiliary tank fuel transfer valve, the auxiliary tank vent valve, and the auxiliary tank Number 2 refuel isolation valve.
If, during the inspection required by paragraph (g) of this AD, any MOV actuator having P/N MA20A1001-1 (S343T003-39) for the fuel tanks is installed: Within 60 months after the effective date of this AD, replace the affected MOV actuator with a serviceable, FAA-approved MOV actuator other than one having P/N MA20A1001-1 (S343T003-39).
Note 1 to paragraph (h) of this AD: Guidance on replacing the affected MOV actuator may be found in the Boeing 767 Aircraft Maintenance Manual or the Boeing 777 Aircraft Maintenance Manual, as applicable.
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.
