Airworthiness Directive · Amendment 39-14274 · Boeing Model 747 Airplanes
Boeing Model 747 Airplanes
This AD applies to Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes; certificated in any category; as identified in Boeing Service Bulletin 747-54A2218, Revision 1, dated February 24, 2005.
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 747 airplanes. This AD requires repetitive inspections of the dual side braces (DSBs), underwing midspar fittings, and associated parts; other specified actions; and corrective actions if necessary. This AD also provides an optional terminating action for the inspections and other specified actions. This AD is prompted by reports of corroded, migrated, and rotated bearings for the DSBs in the inboard and outboard struts, a report of a fractured retainer for the eccentric bushing for one of the side links of a DSB, and reports of wear and damage to the underwing midspar fitting on the outboard strut. We are issuing this AD to prevent the loss of a DSB or underwing midspar fitting load path, which could result in the transfer of loads and motion to other areas of a strut, and possible separation of a strut and engine from the airplane during flight.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
At the times specified in Figure 1 of Boeing Service Bulletin 747-54A2218, Revision 1, dated February 24, 2005, except as provided by paragraph (g) of this AD: Do the various inspections and other specified actions in the figure to detect discrepancies of the DSBs, underwing midspar fittings, and associated parts, by doing all of the actions specified in Parts 1, 2, and 4; and the applicable corrective actions specified in Parts 3, 5, 6, and 7; of the Accomplishment Instructions of the service bulletin, except as provided by paragraph (h) of this AD. Repeat the inspections and other specified actions thereafter at the intervals specified in Figure 1 of the service bulletin. Accomplishment of any terminating action specified in Figure 1 of the service bulletin terminates the inspections and other specified actions for the affected strut.
(g) Where Boeing Service Bulletin 747-54A2218, Revision 1, dated February 24, 2005, recommends an initial compliance threshold of “within 24 months after the original issue date on this service bulletin” for Parts 1 and 4 of the service bulletin, and of “within 72 months after the original issue date on this service bulletin” for Part 2 of the service bulletin, this AD requires an initial compliance threshold of “within 24 months after the effective date of this AD” for Parts 1 and 4 of the service bulletin and of “within 72 months after the effective date of this AD” for Part 2 of the service bulletin.
If any damage or crack is found during any inspection or corrective action required by this AD, before further flight, repair in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-54A2218, Revision 1, dated February 24, 2005; except, where the service bulletin specifies to contact Boeing, before further flight, repair according to a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing Delegation Option Authorization Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.
(i) Inspections and other specified and corrective actions accomplished before the effective date of this AD in accordance with Boeing Alert Service Bulletin 747-54A2218, dated June 17, 2004, are considered acceptable for compliance with the corresponding actions specified in paragraph (f) of this AD.
