Airworthiness Directive · Amendment 39-17658 · Wings
The Boeing Company Airplanes
Superseded. A later AD replaced this one: AD 2015-25-03. Comply with the one in force.
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 747-57A2343, dated September 12, 2013.
We are adopting a new airworthiness directive (AD) for 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. This AD requires inspecting to determine the part number of the inboard actuator attach fittings of the outboard flap. For affected attach fittings, this AD requires doing a detailed inspection of the attach fittings for a cylindrical defect and replacing if necessary. As an option to the detailed inspection, this AD allows replacement of affected attach fittings. This AD was prompted by a report of the fracture of an inboard actuator attach fitting of the outboard flap. An inspection of the attach fitting revealed that it was incorrectly machined with a cylindrical profile instead of a conical profile, resulting in reduced wall thickness. 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.
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, in accordance with Part 1 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2343, dated September 12, 2013.
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 747-57A2343, dated September 12, 2013. 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 747-57A2343, dated September 12, 2013. 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 57A2343, 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 747-57A2343, 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 747-57A2343, dated September 12, 2013.
