Airworthiness Directive · Amendment 39-18709 · Nacelles/pylons
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 777-200, -200LR, -300, -300ER, and 777F series airplanes, certified in any category, as identified in Boeing Special Attention Service Bulletin 777-54-0038, dated March 6, 2015; except for line number 940.
We are superseding Airworthiness Directive (AD) 2006-19-12 for certain The Boeing Company Model 777-200 and -300 series airplanes. AD 2006-19-12 required inspecting the lower web of the aft fairing of the engine struts for any discoloration, and doing related investigative and corrective actions if necessary; inspecting the heat shield castings for any damage and doing corrective action if necessary; installing gap cover strips; and replacing insulation blankets with new insulation blankets. This new AD retains those requirements and also requires, depending on airplane configuration, one-time or repetitive detailed inspections for cracking and deformation, as applicable, of the aft fairing lower structure, and one-time or repetitive conductivity inspections of the aft fairing lower structure, and related investigative and corrective actions if necessary. This new AD also adds airplanes to the applicability. This AD was prompted by a report that an aft fairing lower spar web exceeded the allowable conductivity limits. We are issuing this AD to address the unsafe condition on these products.
This paragraph restates the actions required by paragraph (f) of AD 2006-19-12, with no changes. For Model 777-200 and -300 series airplanes identified in Boeing Special Attention Service Bulletin 777-54-0021, Revision 1, dated March 16, 2006: Except as provided by paragraph (h) of this AD, within 12 months after October 30, 2006 (the effective date of AD 2006-19-12), do the actions specified in paragraphs (g)(1), (g)(2), (g)(3), and (g)(4) of this AD, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-54-0021, Revision 1, dated March 16, 2006.
(1) Do a general visual inspection of the lower web of the aft fairing for any discoloration and do any related investigative action.
(2) Do a general visual inspection of the heat shield castings for any damage (crack(s), dent(s), gouge(s), warpage, fretting, or missing/loose nutplates).
(3) Install gap cover strips on the heat shield pans.
(4) Replace insulation blankets on the heat shield pans with new insulation blankets.
This paragraph restates the actions required by paragraph (g) of AD 2006-19-12, with no changes. If any damage, discoloration, heat damage, or crack is found during any inspection required by paragraph (g) of this AD: Before further flight, do all applicable corrective actions, in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, or in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-54-0021, Revision 1, dated March 16, 2006.
This paragraph restates the credit provided by paragraph (h) of AD 2006-19-12, with a revised format. This paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before October 30, 2006 (the effective date of AD 2006-19-12), using Boeing Special Attention Service Bulletin 777-54-0021, dated June 23, 2005, except where Boeing Special Attention Service Bulletin 777-54-0021, dated June 23, 2005, does not provide an international annealed copper standard (IACS) value for determining the results of the inspection for heat damage, the maximum acceptable IACS value is 42 percent.
(1) For Group 1, Configurations 1, 2, 3, and 4, airplanes; and Group 2, Configurations 1 and 2, airplanes; identified in Boeing Special Attention Service Bulletin 777-54-0038, dated March 6, 2015: Within 24 months after the effective date of this AD, do a detailed inspection of the aft fairing lower structure for any cracking and deformation, and do a conductivity inspection of the aft fairing lower structure for the IACS value (thermal degradation indication), as applicable, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-54-0038, dated March 6, 2015. Do all applicable related investigative and corrective actions before further flight.
(2) For Group 1, Configurations 1 and 3, airplanes, and Group 2, Configuration 1, airplanes, identified in Boeing Special Attention Service Bulletin 777-54-0038, dated March 6, 2015: Repeat the inspections specified in paragraph (j)(1) of this AD thereafter at intervals not to exceed 24 months until the terminating action specified in paragraph (k) of this AD is done.
Accomplishing a detailed inspection of the gap cover strips and heat shield pan castings for damage and applicable corrective actions, and installation of new gap cover strip fillers, new Velcro strips, and improved aft fairing insulation blankets with new batting material, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 777-54-0026, Revision 2, dated January 5, 2012, prior to or concurrently with accomplishing detailed and conductivity inspections and all applicable related investigative and corrective actions required by paragraph (j)(1) of this AD, terminates the repetitive inspections specified in paragraph (j)(2) of this AD; except, where Boeing Service Bulletin 777-54-0026, Revision 2, dated January 5, 2012, specifies to contact the manufacturer, repair using a method approved in accordance with the procedures specified in paragraph (m) 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
