Airworthiness Directive · Amendment 39-18520 · Powerplant
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 787-8 and 787-9 airplanes, certificated in any category, equipped with General Electric GEnx-1B engines, as identified in Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 787-8 and 787-9 airplanes equipped with General Electric engines. This AD was prompted by reports of cracking in barrel nuts on a forward engine mount of Model 747-8 airplanes, which shares a similar design to the forward engine mount of Model 787- 8 and 787-9 airplanes. This AD requires, for certain airplanes, replacement of the four barrel nuts of the forward engine mount on each engine. For certain other airplanes, this AD requires an inspection to determine if any forward engine mount barrel nut having a certain part number is installed; and related investigative and corrective actions if necessary. We are issuing this AD to detect and correct cracking of the forward engine mount barrel nuts. Such cracking could result in reduced load capacity of the forward engine mount and could result in separation of an engine from the airplane and consequent loss of control of the airplane.
For Group 1 airplanes as identified in Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015: Except as provided by paragraph (i)(1) of this AD, at the time specified in paragraph 5., “Compliance,” of Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015, replace the existing forward engine mount barrel nuts on each engine, in accordance with the Accomplishment Instructions of Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015.
For Group 2 airplanes as identified in Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015: Except as provided by paragraph (i)(1) of this AD, at the time specified in paragraph 5. “Compliance,” of Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015, review the aircraft maintenance records to determine if the airplane engine has been removed, installed, or replaced, in accordance with the Accomplishment Instructions of Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015. If the maintenance records indicate that a barrel nut having part number SL4081C14SP1 is installed, or if the part number of an installed barrel nut cannot be determined, before further flight, do the related investigative and applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015.
(1) Where Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015, specifies a compliance time “after the Issue 001 date on this service bulletin,” this AD requires compliance within the specified compliance time after the effective date of this AD.
(2) Where Boeing Service Bulletin B787-81205-SB710026-00, Issue 001, dated June 10, 2015, specifies to contact Boeing for repair instructions: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (j) 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
