Airworthiness Directive · Amendment 39-18341 · Wings
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747SR series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
We are superseding Airworthiness Directive (AD) 2013-23-03, which applies to certain The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747SR series airplanes. AD 2013-23-03 required a detailed inspection of certain attach fittings for a cylindrical defect, and replacement if necessary. For certain airplanes, this new AD requires new inspections of the inboard actuator attach fittings for machining defects, and overhaul or replacement if necessary. This new AD also limits the compliance time for doing the replacement for certain other airplanes. This AD was prompted by a report that a machining defect was also found on some of the actuator assemblies inspected during manufacture. This defect could lead to fatigue cracking and subsequent fracture. We are issuing this AD to detect and correct defective inboard actuator attach fittings which, combined with loss of the outboard actuator load path, could result in uncontrolled retraction of the outboard flap, damage to flight control systems, and consequent reduced controllability of the airplane.
This paragraph restates the requirements of paragraph (g) of AD 2013-23-03, Amendment 39-17658 (78 FR 68345, November 14, 2013), with revised service information. Within 90 days after November 29, 2013 (the effective date of AD 2013-23-03): Inspect to determine the part number of the inboard actuator attach fittings of the outboard flaps, in accordance with Part 1 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, dated September 12, 2013; or Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014. As of the effective date of this AD, only Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014, may be used.
This paragraph restates the requirements of paragraph (h) of AD 2013-23-03, Amendment 39-17658 (78 FR 68345, November 14, 2013), with revised service information. If, during the inspection required by paragraph (g) of this AD, any inboard actuator attach fitting having part number (P/N) 65B08564-7 is found, before further flight, do the actions specified in paragraph (h)(1) or (h)(2) of this AD.
(1) Do a detailed inspection of the inboard actuator attach fitting for a cylindrical defect, in accordance with Part 2 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, dated September 12, 2013; or Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014. As of the effective date of this AD, only Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014, may be used. For airplanes on which the detailed inspection is done before the effective date of this AD: If any cylindrical defect is found, before further flight, do the actions specified in paragraph (h)(1)(i) or (h)(1)(ii) of this AD.
(i) Do a minimum thickness inspection of the inboard actuator attach fitting to determine minimum wall thickness of the actuator fitting assembly, in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, dated September 12, 2013; or Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014. If the minimum thickness of the wall is less than 0.130 inch: Before further flight, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, dated September 12, 2013.
(ii) Replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, dated September 12, 2013.
(2) Replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, dated September 12, 2013; or Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014. As of the effective date of this AD, only Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014, may be used.
For airplanes on which the detailed inspection required by paragraph (h)(1) of this AD is done on or after the effective date of this AD: If any cylindrical defect is found during any inspection required by paragraph (h)(1) of this AD, before further flight, do the actions specified in paragraph (i)(1) or (i)(2) of this AD.
(1) Determine the minimum wall thickness of the actuator attach fitting either by doing an ultrasonic inspection or by mechanically measuring the thickness and do a detailed inspection of the inner conical section to determine if the machining defect is present, in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(i) If the minimum thickness of the wall is less than 0.130 inch: Before further flight, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(ii) If the minimum thickness of the wall is 0.140 inch or greater and the machining defect is present, before further flight, do the actions specified in paragraph (i)(1)(ii)(A) or (i)(1)(ii)(B) of this AD.
(A) Overhaul the inboard actuator attach fitting of the outboard flap, in accordance with Part 5 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(B) Replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(iii) If the minimum thickness of the wall is 0.130 inch or greater and less than 0.140 inch and the machining defect is not present, within 48 months or 3,000 flight cycles after the effective date of this AD, whichever occurs first, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(iv) If the minimum thickness of the wall is 0.130 inch or greater and less than 0.140 inch and the machining defect is present, before further flight, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(2) Replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
If no cylindrical defect is found during any inspection required by paragraph (h)(1) of this AD, within 24 months after the effective date of this AD, do the actions specified in paragraph (j)(1) or (j)(2) of this AD.
(1) Determine the minimum wall thickness of the actuator attach fitting either by doing an ultrasonic inspection or by mechanically measuring the thickness and do a detailed inspection of the inner conical section to determine if the machining defect is present, in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(i) If the minimum thickness of the wall is less than 0.130 inch: Before further flight, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747 57A2443, Revision 1, dated June 23, 2014.
(ii) If the minimum thickness of the wall is 0.140 inch or greater and the machining defect is present, before further flight, do the actions specified in paragraph (j)(1)(ii)(A) or (j)(1)(ii)(B) of this AD.
(A) Overhaul the inboard actuator attach fitting of the outboard flap, in accordance with Part 5 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(B) Replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(iii) If the minimum thickness of the wall is 0.130 inch or greater and less than 0.140 inch and the machining defect is not present, within 48 months or 3,000 flight cycles after the effective date of this AD, whichever occurs first, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(iv) If the minimum thickness of the wall is 0.130 inch or greater and less than 0.140 inch and the machining defect is present, before further flight, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014
(2) Replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
For airplanes on which the detailed inspection required by paragraph (h)(1) of this AD is done before the effective date of this AD, except as required by paragraph (m) of this AD: If any cylindrical defect is found during any inspection required by paragraph (h)(1) of this AD and the replacement of the inboard actuator attach fitting of the outboard flap was not done as specified in Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, within 24 months after the effective date of this AD, do the actions specified in paragraph (k)(1) or (k)(2) of this AD.
(1) Do a detailed inspection of the inner conical section for machining defects and do an ultrasonic inspection to determine the minimum thickness or mechanically determine the minimum thickness, in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014. A review of airplane maintenance records, if available, is acceptable to determine the wall thickness and to determine if there are machining defects, provided wall thickness and machining defects can be positively determined from the records review.
(i) If any machining defect is found and the minimum thickness of the wall is 0.140 inch or greater: Before further flight, do the actions specified in paragraph (k)(1)(i)(A) or (k)(1)(i)(B) of this AD.
(A) Overhaul the inboard actuator attach fitting of the outboard flap, in accordance with Part 5 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(B) Replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(ii) If any machining defect is found and the minimum thickness of the wall is 0.130 inch or greater and less than 0.140 inch: Before further flight, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(iii) If no machining defect is found and the minimum thickness of the wall is 0.130 inch or greater and less than 0.140 inch: Within 48 months or 3,000 flight cycles after the effective date of this AD, whichever occurs first, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(iv) If a machining defect is or is not found and the minimum thickness of the wall is less than 0.130 inch: Before further flight, replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
(2) Replace the inboard actuator attach fitting of the outboard flap, in accordance with Part 4 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2443, Revision 1, dated June 23, 2014.
As of the effective date of this AD, no actuator attach fitting having P/N 65B08564-7 may be installed on any airplane unless the inspection specified in paragraph (h)(1) of this AD is done prior to installation and the applicable actions specified in paragraphs (i) and (j) of this AD are done within the applicable times specified in paragraphs (i) and (j) of this AD. A review of airplane maintenance records, if available, is acceptable to determine if the inspection and applicable actions have been done, provided the inspection and actions can be positively determined from the records review.
For airplanes on which the detailed inspection required by paragraph (h)(1) of this AD is done before the effective date of this AD and the inboard actuator attach fitting was replaced since that inspection: Within 90 days after the effective date of this AD, inspect to determine the part number of the inboard actuator attach fittings of the outboard flaps and, for inboard actuator attach fittings having P/N 65B08564-7, do the applicable actions specified in paragraphs (h), (i), and (j) of this AD within the applicable times specified in paragraphs (h), (i), and (j) of this AD. A review of airplane maintenance records, if available, is acceptable to determine the part number, provided the part number can be positively determined from the records review.
