Airworthiness Directive · Amendment 39-11814 · Boeing Model 777 Series Airplanes
Boeing Model 777 Series Airplanes
Model 777 series airplanes as listed in Boeing Alert Service Bulletin 777-28A0019, dated April 27, 2000; certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 777 series airplanes. This action requires a one-time measurement of the electrical bonding resistance between the wing spar connectors of the fuel quantity indicating system (FQIS) and the spar structure, installation of bonding jumpers, a one- time operational check of the FQIS system, and corrective action, if necessary. This action is necessary to ensure adequate electrical bonding between the wing spar connectors of the FQIS and the spar structure. Inadequate electrical bonding, in the event of a lightning strike, could cause electrical arcing and ignition of fuel vapor in the main or center fuel tank, which could result in a fuel tank explosion. This action is intended to address the identified unsafe condition.
To ensure adequate electrical bonding between the wing spar connectors of the fuel quantity indicating system (FQIS) and the spar structure in the event of a lightning strike, accomplish the following:
(a) Within 90 days after the effective date of this AD: Perform a one-time measurement of the electrical bonding resistance between the wing spar connectors of the FQIS and the spar structure, record the measurements, and install bonding jumpers, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777-28A0019, dated April 27, 2000.
(b) Prior to further flight after accomplishment of the installation required by paragraph (a) of this AD: Perform an operational check in accordance with Boeing Alert Service Bulletin 777-28A0019, dated April 27, 2000, and correct any discrepancy detected.
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.
Aircraft
