Airworthiness Directive · Amendment 39-18346 · Fuselage
The Boeing Company Airplanes
This AD applies to all The Boeing Company Model 777-200, -200LR, -300, -300ER, and 777F series airplanes, certificated in any category.
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 777 airplanes. This AD was prompted by an evaluation by the design approval holder (DAH) indicating that the lap splices of the aft pressure bulkhead webs are subject to widespread fatigue damage (WFD) on aging Model 777 airplanes that have accumulated at least 38,000 total flight cycles. This AD requires repetitive inspections for any crack in the aft webs of the radial lap splices of the aft pressure bulkhead, and, if necessary, corrective actions. We are issuing this AD to detect and correct fatigue cracking in the aft webs of the radial lap splices of the aft pressure bulkhead; such cracking could result in reduced structural integrity of the airplane, decompression of the cabin, and collapse of the floor structure.
Except as required by paragraph (h) of this AD: At the times specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 777-53A0078, dated December 5, 2014, do a medium frequency eddy current inspection for any cracking in the aft webs of the radial lap splices of the aft pressure bulkhead, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777-53A0078, dated December 5, 2014. Repeat the inspection thereafter at intervals not to exceed 8,400 flight cycles from the previous inspection. If any crack is found during any inspection required by this AD, do the applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777-53A0078, dated December 5, 2014. If a corrective action described in Boeing Alert Service Bulletin 777-53A0078, dated December 5, 2014, specifies to contact Boeing for appropriate action: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (i) of this AD.
Where Boeing Alert Service Bulletin 777-53A0078, dated December 5, 2014, specifies a compliance time “after the original issue date of this service bulletin,” this AD requires compliance within the specified compliance time after the effective date of this AD.
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
