Airworthiness Directive · Amendment 39-15765 · Boeing 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
Boeing 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 applies to all Boeing 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.
We are adopting a new airworthiness directive (AD) for all Boeing 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 repetitive inspections for cracks or fractures of the forward end attachment and the forward lower flange of the flap tracks of the trailing edge flaps, and corrective actions if necessary. For certain airplanes, this AD would also require modifying the fail-safe links of the main carriage. This AD results from a detailed structural analysis of the flap attach structural and fail-safe components, accomplished as a result of a dynamic stability and control analysis, which could not demonstrate continued safe flight and landing of the airplane after the loss of a trailing edge flap. We are issuing this AD to detect and correct cracks or fractures of the primary structural and fail-safe load paths of the inboard and outboard trailing edge flaps, which could result in the loss of a flap during takeoff or landing, reducing flightcrew ability to maintain the safe flight and landing of the airplane.
Comply with this AD within the compliance times specified, unless already done.
For all airplanes: Except as provided by paragraph (h) of this AD, at the applicable times specified in paragraph 1.E. of Boeing Alert Service Bulletin 747-57A2323, dated February 21, 2008, inspect for cracks or fractures of the forward end attachment and the forward lower flange of the flap tracks of the trailing edge flaps, and do all applicable corrective actions, by doing all the actions specified in Parts 1 and 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2323, dated February 21, 2008, except as provided by paragraph (i) of this AD. Do all applicable corrective actions before further flight. Repeat the applicable inspection at the applicable time specified in paragraph 1.E. of Boeing Alert Service Bulletin 747-57A2323, dated February 21, 2008.
For Groups 1, 2, and 3 airplanes: Within 24 months after the effective date of this AD, replace the fail-safe links, pins, and attachment hardware in accordance with Part 2 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-57A2323, dated February 21, 2008.
Where Boeing Alert Service Bulletin 747-57A2323, dated February 21, 2008, specifies counting the compliance time from “* * * the date on this service bulletin,” this AD requires counting the compliance time from the effective date of this AD.
(i) If any fractured support fitting is found during any inspection required by this AD, and Boeing Alert Service Bulletin 747-57A2323, dated February 21, 2008, specifies to contact Boeing for appropriate action: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (j) of this AD.
