Airworthiness Directive · Amendment 39-16549 · Fuselage
The Boeing Company Model 747-200C, -200F, -400, -400D, and -400F Series Airplanes
Superseded. A later AD replaced this one: AD 2016-04-02. Comply with the one in force.
This AD applies to The Boeing Company Model 747-200C, -200F, -400, -400D, and -400F series airplanes, certificated in any category; as identified in Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010.
The FAA is superseding an existing airworthiness directive (AD), which applies to certain Model 747-200C, -200F, -400, -400D, and -400F series airplanes. That AD currently requires repetitive inspections for cracks in the overlapping (upper) skin of the upper fastener row of the lap joints of the fuselage skin in sections 41, 42, and 46; and related investigative and corrective actions, if necessary. This new AD expands the inspection area in the existing AD, and adds a modification of certain lap joints and certain post-repair inspections of the lap joints. Accomplishing the modification would end the repetitive inspections required by the existing AD for the length of lap joint that is modified. This AD results from a structural review of affected skin lap joints for widespread fatigue damage. We are issuing this AD to prevent fatigue cracking in certain lap joints, which could result in rapid depressurization of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
For airplanes identified in Boeing Alert Service Bulletin 747-53A2499, dated August 11, 2005: At the applicable time specified in Table 1 of this AD, do an external surface high frequency eddy current (HFEC), external low frequency eddy current (LFEC), and internal LFEC inspection, as applicable, for cracks in the overlapping (upper) skin of the upper fastener row of the lap joints of the fuselage skin in sections 41, 42, and 46, and any applicable related investigative and corrective actions by doing all of the actions in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2499, dated August 11, 2005; Revision 1, dated October 30, 2008; or Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010. Do any applicable related investigative and corrective actions before further flight. As of the effective date of this AD, only Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010, may be used.
| For airplanes on which Structural Significant Items (SSIs) F-25G, F-25H, and F-25I— | Inspect— |
|---|---|
| (1) Have not been inspected in accordance with paragraph (i) of AD 2004-07-22 R1, Amendment 39-15326, using the HFEC method | Before the accumulation of 22,000 total flight cycles, or within 1,000 flight cycles after April 13, 2006 (the effective date of AD 2006-05-09), whichever occurs later. |
| (2) Have been inspected in accordance with paragraph (i) of AD 2004-07-22 R1, using the HFEC method | Within 3,000 flight cycles after the most recent supplemental structural inspection document (SSID) inspection of each applicable structural significant item (as given in Boeing Document D6-35022, “SSID for Model 747 Airplanes,” Revision G, dated December 2000), or within 1,000 flight cycles after April 13, 2006, whichever occurs later. |
Repeat the applicable inspections required by paragraph (g) of this AD thereafter at intervals not to exceed those specified in paragraph 1.E., “Compliance,” (including the note) of Boeing Alert Service Bulletin 747-53A2499, dated August 11, 2005; Revision 1, dated October 30, 2008; or Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010. As of the effective date of this AD, only Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010, may be used.
(i) For all airplanes: Do an external HFEC inspection of the lap joints in Sections 41, 42, and 46 for cracks, by doing all the actions, including all applicable related investigative and corrective actions, specified in the Accomplishment Instructions of Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010. Do the inspection at the applicable time specified in paragraph 1.E. of Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010; except as required by paragraph (m) of this AD. Do all applicable related investigative and corrective actions before further flight. Repeat the inspection thereafter at the times specified in paragraph 1.E. of Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010. Accomplishment of the inspections required by this paragraph terminates the inspections required by paragraphs (g) and (h) of this AD.
(j) For areas on which a lap joint repair was installed and the repair doubler is greater than or equal to 40 inches long: Do initial and repetitive internal HFEC inspections for cracks by doing all the actions, including all applicable corrective actions, specified in the Accomplishment Instructions of Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010, except as required by paragraph (l) of this AD. Do the inspections and corrective actions at the times specified in paragraph 1.E. of Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010, except as required by paragraph (m) of this AD.
Modify the applicable lap joints in Sections 41 and 42 by doing all the applicable actions specified in the Accomplishment Instructions of Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010, at the time specified in paragraph 1.E. of Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010; except as required by paragraphs (l) and (m) of this AD. Accomplishing this modification terminates the repetitive inspections of the skin lap joints in Sections 41 and 42 required by paragraphs (i) and (j) of this AD for the length of lap joint that is modified.
Where Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010, specifies to contact Boeing for appropriate action: Before further flight, repair the crack using a method approved in accordance with the procedures specified in paragraph (o) of this AD.
(m) Where Boeing Service Bulletin 747-53A2499, Revision 2, dated August 12, 2010, specifies a compliance time after the date of that service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.
Actions done before the effective date of this AD in accordance with Boeing Alert Service Bulletin 747-53A2499, Revision 1, dated October 30, 2008, are acceptable for compliance with the corresponding requirements of this AD.
