Airworthiness Directive · Amendment 39-18479 · Wings
The Boeing Company Airplanes
This AD applies to all The Boeing Company Model 777-200, -200LR, -300, and -300ER series airplanes, certificated in any category.
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 777-200, -200LR, -300, and -300ER series airplanes. This AD was prompted by reports of fractured forward attach fittings of the inboard flap outboard aft flap track. The fractured fittings were determined to be the result of corrosion pits forming on the inside diameter of the fittings. This AD requires an inspection for the affected part number and serial number of the main flap; various additional repetitive inspections of the fitting, if necessary; and replacement of the fitting or nested bushing installation, if necessary, which would terminate the inspections. This AD also provides an optional terminating action for the repetitive inspections. We are issuing this AD to detect and correct fracture of the fitting, which could result in the loss of the inboard aft flap and could lead to a punctured fuselage, causing injury to the flightcrew and passengers, and damage to the airplane.
At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, except as provided by paragraph (l) of this AD: Do an inspection of the main flap of the inboard flap assembly for affected part and serial numbers, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014. A review of airplane maintenance records is acceptable in lieu of this inspection if the part number and serial number of the inboard flap can be conclusively determined from that review.
If any main flap of the inboard flap assembly having an affected part number and serial number is found during the inspection required by paragraph (g) of this AD: Except as provided by paragraph (l) of this AD, at the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, do the terminating action specified in paragraph (k)(1), (k)(2), or (k)(3) of this AD, or do the inspections specified in paragraph (h)(1) or (h)(2) of this AD, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014. Repeat the inspections thereafter at the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, until a terminating action in paragraph (k)(1), (k)(2), or (k)(3) of this AD is done. Accomplishing a terminating action specified in paragraph (k)(1), (k)(2), or (k)(3) of this AD terminates the inspections required by this paragraph for that fitting only.
(1) At the forward attach fitting of the aft flap track of the inboard flap: Do a detailed inspection for cracking and bushing migration, and a high frequency eddy current inspection for cracking, in accordance with Part 2 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
(2) At the forward attach fitting of the aft flap track of the inboard flap: Do a detailed inspection for cracking and bushing migration, and an ultrasound inspection for cracking, in accordance with Part 3 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
If any bushing migration but no cracking is found during any inspection required by paragraph (h) of this AD: At the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, do the actions specified in paragraphs (i)(1) through (i)(3) of this AD. Accomplishment of a terminating action specified in paragraph (i)(3) or (k) of this AD terminates the actions required by this paragraph for that fitting only.
(1) Apply corrosion inhibiting compound BMS 3-23, Type II, around the bushing flanges on each side of the fitting, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014. Re-apply the corrosion inhibiting compound at the time specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
(2) Repeat the inspections specified in paragraph (h)(1) or (h)(2) of this AD, except inspect for cracking only.
(3) Do a terminating action specified in paragraph (i)(3)(i), (i)(3)(ii), or (i)(3)(iii) of this AD.
(i) Install a nested bushing to the forward attach fitting of the aft flap track of the inboard flap, including doing all applicable related investigative actions, in accordance with Part 4 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
(ii) Replace the forward attach fitting of the aft flap track of the inboard flap with an aluminum fitting, including doing all applicable related investigative actions, in accordance with Part 5 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
(iii) Replace the forward attach fitting of the aft flap track of the inboard flap with a titanium fitting, including doing all applicable related investigative actions, in accordance with Part 6 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
If any cracking is found during any inspection required by paragraph (h) or (i)(3) of this AD: At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, do a terminating action specified in paragraph (j)(1) or (j)(2) of this AD. Replacement of the forward attach fitting as specified in paragraph (j)(1) or (j)(2) of this AD terminates the actions in this AD for that fitting only.
(1) Replace the forward attach fitting of the aft flap track of the inboard flap with an aluminum fitting, including doing all applicable related investigative and corrective actions, in accordance with Part 5 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
(2) Replace the forward attach fitting of the aft flap track of the inboard flap with a titanium fitting, including doing all applicable related investigative and corrective actions, in accordance with Part 6 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
(1) Installation of the nested bushing to the forward attach fitting of the aft flap track of the inboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, terminates the requirements of this AD for that fitting only, provided no cracking is found during any inspection specified in Part 4 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, and all corrosion has been removed.
(2) Replacement of the forward attach fitting of the aft flap track of the inboard flap with an aluminum fitting, in accordance with Part 5 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, terminates the requirements of this AD for that fitting only.
(3) Replacement of the forward attach fitting of the aft flap track of the inboard flap with a titanium fitting, in accordance with Part 6 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, terminates the requirements of this AD for that fitting only.
Where Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, dated November 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
