Airworthiness Directive · Amendment 39-18513 · Nacelles/pylons
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 777-200 and -300 series airplanes equipped with Rolls-Royce Trent 800 series engines, certificated in any category, as identified in Boeing Service Bulletin 777-54A0031, Revision 1, dated May 9, 2014.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777-200 and -300 series airplanes equipped with Rolls-Royce Trent 800 series engines. This AD was prompted by reports of heat damage to the strut aft fairing heat shield primary seal, as well as heat and wear damage to the heat shield insulation blankets. This AD requires repetitive inspections for cracks and heat damage to the strut aft fairing lower spar web structure (a flammable fluid zone barrier), for wear to the heat shield primary seal, and, as applicable, for heat and wear damage to heat shield insulation blankets; and related investigative and corrective actions if necessary. This AD also provides optional terminating action for the repetitive inspections. We are issuing this AD to detect and correct cracks and heat damage to the strut aft fairing lower spar web structure (a flammable fluid zone barrier), wear to the heat shield primary seal, and heat and wear damage to heat shield insulation blankets, which could lead to through-cracks in the aft fairing lower web structure and heating of the aft fairing lower web structure, and consequent uncontrolled fire in the aft fairing, fuel tank ignition or possible departure of the engine.
At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 777-54A0031, Revision 1, dated May 9, 2014, except as required by paragraph (i) of this AD: Do the inspections specified in paragraphs (g)(1), (g)(2), and (g)(3) of this AD, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 777-54A0031, Revision 1, dated May 9, 2014. Do all applicable related investigative and corrective actions before further flight. Repeat the inspections specified in paragraphs (g)(1), (g)(2), and (g)(3) of this AD at the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 777-54A0031, Revision 1, dated May 9, 2014.
(1) Do a detailed inspection for cracks and heat damage of the aft fairing lower spar upper surface.
(2) Do a conductivity inspection for heat damage of the aft fairing lower spar upper surface.
(3) Do a detailed inspection for wear of the heat shield primary seal.
The concurrent accomplishment of the actions specified in paragraphs (h)(1) and (h)(2) of this AD terminates the requirements of paragraph (g) of this AD.
(1) Replacement of all heat shield insulation blankets (rub strips, heat shield pan casting, Velcro strips, aft fairing web drain sump, drain screen, and drain tubes, as applicable) in accordance with the Accomplishment Instructions of Boeing Service Bulletin 777-54-0030, Revision 1, dated September 30, 2015.
(2) A one-time detailed inspection for cracks and heat damage of the aft fairing lower spar upper surface, conductivity inspection for heat damage of the aft fairing lower spar upper surface, and detailed inspection for wear of heat shield primary seal, and all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 777-54A0031, Revision 1, dated May 9, 2014, provided all applicable related investigative and corrective actions are done before further flight.
Where Boeing Service Bulletin 777-54A0031, Revision 1, dated May 9, 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
