E9-19262. Airworthiness Directives; Boeing Model 747-200C and -200F Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Boeing Model 747-200C and -200F series airplanes. The existing AD currently requires repetitive inspections to find fatigue cracking in the floor panel attachment fastener holes of the upper chord of certain upper deck floor beams in Section 41 (i.e., body station 520 and forward), and repair if necessary. The existing AD also provides optional modifications, which extend the threshold for the initiation of certain repetitive inspections. This proposed AD would add repetitive inspections to find fatigue cracking in the floor panel attachment fastener holes of the upper chord of certain other upper deck floor beams in Section 41 and Section 42 (i.e., aft of body station 520); repetitive inspections to find fatigue cracking in the permanent fastener holes of the upper chord of certain upper deck floor beams in Section 41; and related investigative and corrective actions. This proposed AD would also provide a new optional modification, which would terminate certain repetitive inspections. This proposed AD results from new reports of cracking in the upper chord of the upper deck floor beams in Sections 41 and 42, and new analysis that shows the permanent fastener holes of the upper chord of certain upper deck floor beams in Section 41 are also susceptible to fatigue cracking. We are proposing this AD to detect and correct cracking in the upper chord of the upper deck floor beams. Such cracking could extend and sever the floor beams, which could result in rapid decompression and loss of controllability of the airplane.

DATES:

We must receive comments on this proposed AD by September 28, 2009.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone [phone], extension 1, fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221 or 425-227-1152.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2009-0684; Directorate Identifier 2008-NM-149-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

On March 31, 2006, we issued AD 2006-08-02, amendment 39-14556 (70 FR 18618, April 12, 2006), for certain Boeing Model 747-200C and -200F series airplanes. That AD requires repetitive inspections to find fatigue cracking in the floor panel attachment fastener holes of the upper chord of certain upper deck floor beams in Section 41 (i.e., body station 520 and forward), and repair if necessary. That AD also provides optional modifications, which extend the threshold for initiating certain repetitive inspections. That AD resulted from new reports of cracks in the upper deck floor beams occurring at lower total flight cycles. We issued that AD to find and fix cracking in the upper chord of certain upper deck floor beams in Section 41. Such cracking could extend and sever the floor beams, which could result in rapid decompression and loss of controllability of the airplane.

Actions Since Existing AD Was Issued

Since we issued AD 2006-08-02, several operators of Boeing Model 747-400D series airplanes have reported cracking in the floor panel attachment fastener holes of the upper chord of the upper deck floor beams at body stations (BS) 460 and 480, and at the upper chord of the floor beams in Section 42. The upper deck floor beams of Model 747-200C and 747-200F series airplanes are of similar type design to Model 747-400D series airplanes at those locations; therefore, we have concluded that the unsafe condition also exists on Model 747-200C and 747-200F series airplanes. In addition, Boeing has done analysis that shows certain permanent fastener holes of the upper chord of certain upper deck floor beams in Section 41 are also susceptible to fatigue cracking.

Other Relevant Rulemaking

On December 26, 2007, we issued AD 2004-07-22 R1, amendment 39-15326 (73 FR 1052, January 7, 2008), 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, 747SR, and 747SP series airplanes. (A correction of the final rule was published in the Federal Register on February 14, 2008 (73 FR 8589).) That AD requires that the FAA-approved maintenance inspection program be revised to include inspections that will give no less than the required damage tolerance rating for each structural significant item, and repair of cracked structure. We issued that AD to ensure the continued structural integrity of the affected Model 747 series airplanes.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008 (“Revision 2 of the service bulletin”). (We referred to Boeing Alert Service Bulletin 747-53A2439, Revision 1, dated March 10, 2005, as the appropriate source of service information for accomplishing the actions required by AD 2006-08-02.) Revision 2 of the service bulletin adds procedures for repetitive open-hole or surface high-frequency eddy current (HFEC) inspections to find fatigue cracking in the upper chord of the upper deck floor beams at body stations (BS) 460 and 480, and from BS 540 to 780 (specified as Area 5 in the service bulletin). Revision 2 of the service bulletin also adds procedures for inspections to find fatigue cracking in the permanent fastener holes of the upper chord of certain upper deck floor beams in Section 41.

For airplanes on which any crack is found, Revision 2 of the service bulletin specifies the corrective action of repairing the crack before further flight. The repair depends on the location and extent of cracking and can involve oversizing the fastener hole, installing a repair strap or angle, or contacting Boeing for repair instructions.

Revision 2 of the service bulletin also specifies post-repair inspections and corrective actions that include:

• Repair of any cracking before further flight. For airplanes on which a crack is found in a previously repaired or modified area, the service bulletin specifies contacting Boeing for repair data.
• An additional HFEC inspection for cracking of areas that have been repaired or modified.

Revision 2 of the service bulletin also describes optional (alternative) modification procedures for airplanes on which no cracking is found. Accomplishing these modifications extends the threshold for initiating certain repetitive inspections.

Revision 2 of the service bulletin defines the area for the new floor panel attachment fastener hole inspections as “Area 5.” The Area 5 inspections start at the latest of the following times:

• Before the accumulation of 20,000 total flight cycles.
• Within 1,000 flight cycles after the date of the service bulletin.
• Within 2,000 flight cycles after the last surface HFEC inspection or 6,000 flight cycles after the last open-hole HFEC inspection done in accordance with Supplemental Structural Inspection Document (SSID) SSI F-19B only (required by AD 2004-07-22 R1).

Revision 2 of the service bulletin also specifies additional inspection of permanent fastener holes in “Areas 1, 2, 3 and 4.” This new inspection starts at the later of the following times:

• Before the accumulation of 15,000 total flight cycles.
• Within 1,000 flight cycles after the date of the service bulletin.

The repetitive inspection interval depends on the inspection method and previous repairs/modifications, and ranges from 2,000 to 6,000 flight cycles for the surface/open-hole HFEC inspections.

Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.

Revision 2 of the service bulletin refers to Boeing Alert Service Bulletin 747-53A2696, dated October 16, 2008, for certain modifications. The actions in Boeing Alert Service Bulletin 747-53A2696 have been approved as an alternative method of compliance (AMOC) with certain requirements of AD 2006-08-02.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to develop on other airplanes of the same type design. For this reason, we are proposing this AD, which would supersede AD 2006-08-02 and would retain the requirements of the existing AD. This proposed AD would also require accomplishing the actions specified in the service information described previously except as discussed under “Differences Between the Proposed AD and the Service Bulletin.”

Differences Between the Proposed AD and the Service Bulletin

Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008, specifies to contact the manufacturer for instructions on how to repair certain conditions, but this proposed AD would require repairing those conditions in one of the following ways:

• Using a method that we approve; or
• Using data that meet the certification basis of the airplane, and that have been approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization whom we have authorized to make those findings.

Explanation of Changes Made to This AD

We have added new paragraph (d) to this proposed AD specifying the Air Transport Association (ATA) of America code identifying the subject of the AD, and have re-identified the subsequent paragraphs accordingly.

We have simplified paragraph (h)(1) of this proposed AD (which corresponds to paragraph (g)(1) of AD 2006-08-02) by referring to the “Alternative Methods of Compliance (AMOCs)” paragraph of this AD for repair methods.

We have revised paragraph (h)(1) of this proposed AD to allow any crack in the subject area to be repaired according to data that conform to the airplane's type certificate and that are approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization whom we have authorized to make such findings.

Costs of Compliance

There are about 68 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

Estimated Costs

Action	Work hours	Average labor rate per hour	Cost per airplane	Number of U.S.-registered airplanes	Fleet cost
Inspections (required by AD 2006-08-02)	29	$80	$2,320 per inspection cycle	25	$58,000 per inspection cycle.
Inspection of Area 5 and permanent fastener hole in Areas 1, 2, 3, and 4 (new proposed action)	78	80	$6,240 per inspection cycle	25	$156,000 per inspection cycle.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that the proposed regulation:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

3. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by removing amendment 39-14556 (70 FR 18618, April 12, 2006) and adding the following new AD:

Boeing: Docket No. FAA-2009-0684; Directorate Identifier 2008-NM-149-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by September 28, 2009.

Affected ADs

(b) This AD supersedes AD 2006-08-02.

Applicability

(c) This AD applies to Boeing Model 747-200C and -200F series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008.

Subject

(d) Air Transport Association (ATA) of America Code 53: Fuselage.

Unsafe Condition

(e) This AD results from new reports of cracking in the upper chord of the upper deck floor beams in Sections 41 and 42, and new analysis that shows the permanent fastener holes of the upper chord of certain upper deck floor beams in Section 41 are also susceptible to fatigue cracking. We are issuing this AD to detect and correct cracking in the upper chord of the upper deck floor beams. Such cracking could extend and sever the floor beams, which could result in rapid decompression and loss of controllability of the airplane.

Compliance

(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Requirements of AD 2006-08-02

Initial Compliance Time at a New Reduced Threshold

(g) At the earliest of the times specified in paragraphs (g)(1) through (g)(3) of this AD, do the inspection required by paragraph (h) of this AD.

(1) Before the accumulation of 22,000 total flight cycles, or within 1,000 flight cycles after March 15, 2004 (the effective date of AD 2004-03-11, which was superseded by AD 2006-08-02), whichever occurs later.

(2) For airplanes with 17,000 or more total flight cycles as of May 17, 2006 (the effective date of AD 2006-08-02): Before the accumulation of 18,000 total flight cycles, or within 90 days after May 17, 2006, whichever occurs later.

(3) For airplanes with fewer than 17,000 total flight cycles as of May 17, 2006: Before the accumulation of 15,000 total flight cycles, or within 1,000 flight cycles after May 17, 2006, whichever occurs later.

Inspections at Reduced Intervals for Certain Floor Beams and Repair

(h) Do the applicable inspection to find fatigue cracking in the upper chord of the upper deck floor beams as specified in Part 1 (Open-Hole High Frequency Eddy Current (HFEC) Inspection Method) or Part 2 (Surface HFEC Inspection Method) of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001. Do the inspections per the Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001, except as provided by paragraph (k) of this AD. Any combination of the applicable inspection methods specified in Parts 1 and 2 may be used, provided that the corresponding repetitive inspection interval is used.

(1) If any crack is found, before further flight, repair per Part 3 (Upper Chord Repair) of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001; except where Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001, specifies to contact Boeing for appropriate action, before further flight, repair using a method approved in accordance with the procedures specified in paragraph (o) of this AD or repair according to data meeting the certification basis of the airplane approved by a Boeing Company Designated Engineering Representative (DER) or by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization. For a repair method to be approved by the Manager, Seattle Aircraft Certification Office (ACO), as required by this paragraph, the Manager's approval letter must specifically reference this AD. Do the applicable inspection of the repaired area per Part 1 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001, at the applicable time per Part 3 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001, and repeat the applicable inspection at the applicable interval per Figure 1 of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001.

(2) If no crack is found, repeat the applicable inspection per paragraph (h) of this AD at the applicable time specified in paragraphs (h)(2)(i) through (h)(2)(iii) of this AD. As an option to the repetitive inspections, accomplishment of paragraph (i)(1) or (i)(2) of this AD, before further flight, extends the threshold for the initiation of the repetitive inspections required by this paragraph.

(i) If the immediately preceding inspection was conducted using an open-hole HFEC inspection method: Conduct the next inspection of that area within 3,000 flight cycles of the last inspection.

(ii) If the immediately preceding inspection was conducted using a surface HFEC inspection method at stations 340 through 420 inclusive and station 500: Conduct the next inspection of that area within 750 flight cycles of the last inspection.

(iii) If the immediately preceding inspection was conducted using a surface HFEC inspection method at stations 440 and 520: Conduct the next inspection of that area at the earlier of the times specified in paragraphs (h)(2)(iii)(A) and (h)(2)(iii)(B) of this AD, and thereafter at intervals not to exceed 250 flight cycles.

(A) Within 750 flight cycles since the last surface HFEC inspection required by paragraph (h) of this AD.

(B) Within 250 flight cycles after May 17, 2006.

Optional Repair/Modification

(i) For areas on which the inspection required by paragraph (h) of this AD is done per Part 1 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001; and on which no cracking is found: Accomplishment of the actions specified in either paragraph (i)(1) or (i)(2) of this AD extends the threshold for the initiation of the repetitive inspections required by paragraph (h)(2) of this AD. For areas on which the inspection required by paragraph (h) of this AD is done per Part 2 of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001; and on which no cracking is found: Accomplishment of the actions specified in paragraph (i)(1) of this AD extends the threshold for the initiation of the repetitive inspections required by paragraph (h)(2) of this AD.

(1) Do the applicable repair per Part 3 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001, except as provided by paragraph (k) of this AD. At the applicable time specified in Table 1 of Part 3 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001, do the applicable inspection of the repaired area per Part 1 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001. Repeat the inspection thereafter within the applicable interval of 3,000 flight cycles per Figure 1 of the service bulletin.

(2) Do the modification of the attachment hole of the floor panel per Figure 5 of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001, except as provided by paragraph (k) of this AD. Within 10,000 flight cycles after accomplishment of the modification, do the inspection of the modified area per Part 1 of the Work Instructions of the service bulletin. Repeat the inspection thereafter within the applicable interval of 3,000 flight cycles per Figure 1 of Boeing Alert Service Bulletin 747-53A2439, dated July 5, 2001.

Determining the Number of Flight Cycles for Compliance Time

(j) For the purposes of calculating the compliance threshold and repetitive intervals for actions required by paragraphs (g), (h), or (i) of this AD: As of May 17, 2006 (the effective date of AD 2006-08-02), all flight cycles, including the number of flight cycles in which cabin differential pressure is at 2.0 pounds per square inch (psi) or less, must be counted when determining the number of flight cycles that have occurred on the airplane.

New Requirements of This AD

Applicable Revisions of Service Bulletins

(k) Use the information in Tables 1 and 2 of this AD, at the applicable time specified in paragraphs (k)(1) and (k)(2) of this AD, to determine the part of the applicable service bulletin to use to accomplish the actions required by this AD.

(1) On or after May 17, 2006, but before the effective date of this AD, use only the service information listed in Table 1 or Table 2 of this AD.

Table 1—Service Information Given in Boeing Alert Service Bulletin 747-53A2439, Revision 1, Dated March 10, 2005

Do—	In accordance with—
(1) The actions required by paragraph (h) of this AD	Parts 1 and 2 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 1, dated March 10, 2005; as applicable.
(2) The applicable inspection of the repaired area required by paragraph (h)(1) of this AD	Parts 1 and 6 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 1, dated March 10, 2005; as applicable; at the applicable time specified in Table 1 of Part 3 of the Work Instructions of that service bulletin.
(3) The actions required by paragraph (i)(1) of this AD	Parts 1, 3, and 6 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 1, dated March 10, 2005.
(4) The actions required by paragraph (i)(2) of this AD	Figure 5 and Part 1 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 1, dated March 10, 2005; as applicable.

(2) On or after the effective date of this AD, use only the service information listed in Table 2 of this AD.

Table 2—Service Information Given in Boeing Alert Service Bulletin 747-53A2439, Revision 2, Dated July 17, 2008

Do—	In accordance with—
(1) The actions required by paragraph (h) and (l) of this AD	Part 1 (open-hole or surface HFEC inspection, as applicable) of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008.
(2) The applicable inspection of the repaired area required by paragraph (h)(1) of this AD	Part 1 (open-hole HFEC inspection only) and Part 5 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008; at the applicable time specified in Table 1 of Part 2 of the Work Instructions of that service bulletin.
(3) The applicable repair required by paragraph (h)(1) of this AD	Part 2 (upper chord repair at floor panel attach holes) of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008.
(4) The actions required by paragraph (i)(1) of this AD	Part 1 (open-hole HFEC inspection only), Part 2, and Part 5 of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008.
(5) The actions required by paragraph (i)(2) of this AD	Figure 5 and Part 1 (open-hole HFEC inspection only) of the Work Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008.

New Inspections and Related Investigative and Corrective Actions

(l) For all airplanes, except as provided by paragraphs (k)(1) and (k)(2) of this AD: At the applicable time specified in Paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008, do the applicable open-hole or surface HFEC inspections for fatigue cracking in the upper chord of the upper deck floor beams in Area 5, and the inspection for fatigue cracking in the permanent fastener holes of the upper chord of certain upper deck floor beams in Areas 1, 2, 3, and 4, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008. Do all applicable related investigative and corrective actions before further flight. Repeat the applicable inspection thereafter at the applicable interval specified in Paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008.

(1) Where Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008, specifies a compliance time relative to the date of issuance of that service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.

(2) Where Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008, specifies contacting Boeing for repair data: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (o) of this AD.

Optional New Modification for Areas 1, 2, 3, and 4

(m) For areas 1, 2, 3, and 4 as defined in Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008: Doing the modification and post-modification actions specified in Boeing Alert Service Bulletin 747-53A2696, dated October 16, 2008, terminates the repetitive inspection requirements of paragraphs (g) and (h) of this AD. Doing the modification and post-modification actions specified in Boeing Alert Service Bulletin 747-53A2696, dated October 16, 2008, terminates the repetitive inspection requirements of paragraph (l) of this AD, except at the upper deck floor beam at body station (BS) 460 and 480 and the upper deck floor beams aft of BS 520.

No Reporting Requirement

(n) Although Boeing Alert Service Bulletin 747-53A2439, Revision 1, dated March 10, 2005; and Boeing Alert Service Bulletin 747-53A2439, Revision 2, dated July 17, 2008; specify to submit certain information to the manufacturer, this AD does not include that requirement.

Alternative Methods of Compliance (AMOCs)

(o)(1) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone]. Or, e-mail information to [e-mail].

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

(3) AMOCs approved previously in accordance with AD 2006-08-02, are approved as AMOCs for the corresponding provisions of this AD.

(4) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Commercial Airplanes 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.

Issued in Renton, Washington, on August 3, 2009.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.