Airworthiness Directive · Amendment 39-16212 · Standard practices/structures
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
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 adopting a new airworthiness directive (AD) for all 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. This AD requires one-time detailed and high frequency eddy current inspections for cracks in the wing and horizontal stabilizer side-of-body joints and the fuselage skin circumferential splices, and repair if necessary. This AD also requires, for certain airplanes, repetitive detailed inspections for cracks of the fuselage skin circumferential splices, and repair if necessary. This AD results from Boeing analysis indicating that the wing and horizontal stabilizer side-of-body joints, and the fuselage skin circumferential splices, are susceptible to fatigue cracking due to high cyclic loads on the airplane. We are issuing this AD to detect and correct fatigue cracking at multiple adjacent locations in the subject areas, which could connect to form large cracks and result in reduced structural integrity leading to rapid decompression and consequent loss of control 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.
Except as provided by paragraphs (h) and (i) of this AD: At the applicable times specified in paragraph 1.E. of Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008, do one-time inspections for cracks in the wing and horizontal stabilizer side-of-body joints, and the fuselage skin circumferential splices; do detailed inspections, as applicable, for cracks of the fuselage skin circumferential splices; and do all applicable repairs before further flight, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008, except as provided by paragraphs (j) and (k) of this AD. As applicable, repeat the detailed inspection for cracks of the fuselage skin circumferential splices, at the applicable times specified in paragraph 1.E. of Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008.
Note 1: The inspection specified in Sheet 6 of Figure 31 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008, is an external detailed inspection of the fuselage skin as specified in Step 3 of Figure 31, not an inspection of the fuselage stringer.
Where Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008, specifies a compliance time after “* * * the date on this service bulletin,” this AD requires compliance within the specified compliance time after the effective date of this AD.
(i) Where Note (a) of Table 2 of paragraph 1.E. of Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008, specifies that if a certain modification was done then certain inspections may be deferred “until the post modification inspection period as given in Service Bulletin 747-57A2314,” this AD allows, for airplanes on which the modification specified in Boeing Service Bulletin 747-57A2314 has been done, deferring the inspections specified in Part 2 of paragraph 3.B., Work Instructions, of Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008, until the applicable post-modification inspection compliance times required by paragraph (e) of AD 2004-03-09, amendment 39-13453.
For Group 6 airplanes identified in Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008: Do the inspections specified in Part 4 of paragraph 3.B., Work Instructions, of Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008, in accordance with the procedures specified in paragraph (m) of this AD.
If any crack is found during any inspection required by this AD, and Boeing Alert Service Bulletin 747-51A2060, dated October 30, 2008, specifies to contact Boeing for appropriate action: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (m) of this AD.
At the applicable time specified in paragraph (l)(1) or (l)(2) of this AD, submit a report of positive findings of cracks found during the inspection required by paragraph (g) of this AD to Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Alternatively, operators may submit reports to their Boeing field service representatives. The report must contain, as a minimum, the following information: airplane serial number, flight cycles at time of discovery, location(s) and extent of positive crack findings. Under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements contained in this AD and has assigned OMB Control Number 2120-0056.
(1) If the inspection was done on or before the effective date of this AD: Send the report within 30 days after the effective date of this AD.
(2) If the inspection was done after the effective date of this AD: Send the report within 30 days after the inspection is done.
