Airworthiness Directive · Amendment 39-18438 · Fuselage
The Boeing Company Airplanes
This AD applies to all 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, 747SR, and 747SP series airplanes, certificated in any category.
We are superseding Airworthiness Directive (AD) 2006-22-15 for all 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, 747SR, and 747SP series airplanes. AD 2006-22-15 required repetitive inspections for cracking of certain panel webs and stiffeners of the nose wheel well (NWW), and corrective actions if necessary; and replacement of certain panels with new panels, which terminates the repetitive inspections. This new AD reduces a compliance time and adds certain inspections and an applicable repair. This AD was prompted by multiple reports of fatigue cracking in the NWW top panel and side panel webs and stiffeners. We are issuing this AD to prevent fatigue cracking of the NWW side and top panels, which could result in a NWW depressurization event severe enough to reduce the structural integrity of the fuselage.
Except as specified in paragraphs (h)(1) and (h)(2) of this AD, at the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013: Do the actions specified in paragraphs (g)(1), (g)(2), and (g)(3) of this AD, and do all applicable related investigative and corrective actions; in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013, except as specified in paragraph (h)(3) of this AD. Do all applicable related investigative and corrective actions before further flight. Repeat the inspections specified in paragraphs (g)(1), (g)(2), and (g)(3) of this AD thereafter at the applicable intervals specified in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013. The repetitive interval for the inspection of Area 2 specified in table 1 in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013, is 1,000 flight cycles. In table 2 and table 3 in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013, the date “January 27, 2005,” is the effective date of AD 2004-25-23, Amendment 39-13911 (69 FR 76839, December 23, 2004); and the date “May 10, 2005,” is the effective date of AD 2005-09-02, Amendment 39-14070 (70 FR 21141, April 25, 2005; corrected May 25, 2005 (70 FR 29940)).
(1) Do an external detailed inspection for cracks of the top and sidewall panel webs of the NWW (specified as Area 1 and Area 2 in Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013).
(2) Do internal detailed and surface high frequency eddy current (HFEC) inspections for cracks of the sidewall panel and top panel stiffeners of the NWW (specified as Area 3 in Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013).
(3) Do an external detailed and ultrasonic testing (UT) inspection for cracks of the top and sidewall panel webs of the NWW (specified as Area 1 and Area 2 in Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013).
(1) Table 1 in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013, applies to airplanes with less than 15,000 total flight cycles “as of the Revision 5 date of this service bulletin.” For this AD, however, table 1 applies to airplanes with the specified total flight cycles as of the effective date of this AD.
(2) Table 1 in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013, specifies a compliance time of “13,000 total flight-cycles,” or “within 1,000 flight cycles after the Revision 5 date of this service bulletin,” whichever occurs later. This AD requires compliance before the accumulation of 10,000 total flight cycles or within 1,000 flight cycles after the effective date of this AD, whichever occurs later.
(3) If any cracking or damage is found during any inspection required by paragraph (g) of this AD, and Boeing Service Bulletin 747-53A2465, Revision 5, dated July 11, 2013, specifies to contact Boeing for appropriate action: Before further flight, repair the cracking or damage using a method approved in accordance with the procedures specified in paragraph (p) of this AD.
For airplanes identified in Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013: At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013, replace the left-side, right-side, and top panels of the NWW, as applicable, with new panels, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013. As of the effective date of this AD, concurrently with doing the replacement specified in Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013, do a detailed inspection for any cracks or damage (including, but not limited to, dents and corrosion) in all attaching structural elements that are common to the removed top panel and side panels, as applicable, and do all applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013. If any crack or damage is found, before further flight, repair the cracking or damage using a method approved in accordance with the procedures specified in paragraph (p) of this AD. In paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013, the date “December 11, 2006,” is the effective date of AD 2006-22-15.
For airplanes on which the replacement specified in paragraph (i) of this AD has been done: Except as required by paragraph (k) of this AD, at the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013, do the actions specified in paragraphs (j)(1), (j)(2), and (j)(3) of this AD. If any crack is found: Before further flight, repair the cracking using a method approved in accordance with the procedures specified in paragraph (p) of this AD. Repeat the inspections specified in paragraphs (j)(1), (j)(2), and (j)(3) of this AD thereafter at the applicable intervals specified in paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013.
(1) Do an external detailed inspection for cracks in the side panel webs, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013.
(2) Do an internal detailed inspection and high frequency eddy current (HFEC) inspection for cracks in the top and side panel stiffeners, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013.
(3) Do an external detailed inspection for cracks in the top panel web, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013.
Where paragraph 1.E., “Compliance,” of Boeing Service Bulletin 747-53A2562, Revision 3, dated July 11, 2013, specifies a compliance time relative to the “Revision 3 date of this service bulletin,” this AD requires compliance within the specified compliance time after the effective date of this AD.
For airplanes identified in Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012: At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012, replace the left side, right side, and top panels of the NWW, as applicable, with new panels, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012. Concurrently with doing the replacement specified in this paragraph, do a detailed inspection for cracks of the attaching structural elements that are common to the removed top, left side, and right side panels of the NWW, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012. If any crack is found, before further flight, repair the cracking using a method approved in accordance with the procedures specified in paragraph (p) of this AD.
For airplanes on which the replacement specified in paragraph (l) of this AD has been done: At the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012, do the actions specified in paragraphs (m)(1), (m)(2), and (m)(3) of this AD. If any crack is found: Before further flight, repair the cracking using a method approved in accordance with the procedures specified in paragraph (p) of this AD. Repeat the inspections specified in paragraphs (m)(1), (m)(2), and (m)(3) of this AD thereafter at the applicable intervals specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012.
(1) Do an external detailed inspection for cracks in the side panel webs, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012.
(2) Do an internal detailed inspection and HFEC inspection for cracks in the top and side panel stiffeners, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012.
(3) Do an external detailed inspection for cracks in the top panel web, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2808, dated November 30, 2012.
Replacing the left side, right side, and top panels of the NWW with new panels as specified in paragraph (i) or (l) of this AD terminates the repetitive inspections required by paragraph (g) of this AD.
