[Federal Register Volume 76, Number 184 (Thursday, September 22, 2011)]
[Proposed Rules]
[Pages 58722-58726]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-24356]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 76, No. 184 / Thursday, September 22, 2011 / 
Proposed Rules  

[[Page 58722]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0991; Directorate Identifier 2010-NM-134-AD]
RIN 2120-AA64


Airworthiness Directives; the Boeing Company 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 Model 747-100, 747-100B, 747-
200B, 747-200C, 747-200F, 747-400F, 747SR, and 747SP series airplanes, 
without a stretched upper deck or stretched upper deck modification. 
The existing AD currently requires repetitive inspections for cracks of 
each affected tension tie and of the surrounding structure, and related 
investigative and corrective actions if necessary. This proposed AD 
would also require, for certain airplanes, modifying the tension tie 
structure or tension tie and frame structure at certain stations; and a 
post-modification inspection of the modified area and post-modification 
repetitive inspections of the unmodified area, and repair if necessary. 
Doing the modification would terminate the repetitive inspection 
requirements in the existing AD. This proposed AD would reduce the 
compliance time and add inspections for certain airplanes. This 
proposed AD results from reports that certain airplanes have tension 
ties that are susceptible to widespread fatigue damage. This proposed 
AD also results from reports of cracks on the forward and aft tension 
tie channels at station (STA) 740 and STA 760, and a determination that 
initial inspection intervals need to be reduced. We are proposing this 
AD to prevent tension ties from becoming severed or disconnected from 
the frames, which could lead to rapid in-flight decompression.

DATES: We must receive comments on this proposed AD by November 7, 
2011.

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: 202-493-2251.
     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 proposed AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; e-mail [email protected]; 
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.

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 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Steven Fox, Senior Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue, SW., Renton, Washington 98057-3356; phone: 
(425) 917-6425; fax: (425) 917-6590; e-mail: [email protected].

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-2011-0991; 
Directorate Identifier 2010-NM-134-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 December 30, 2005, we issued AD 2006-01-07, Amendment 39-14446 
(71 FR 1947, January 12, 2006), for certain Model 747-100, 747-100B, 
747-200B, 747-200C, 747-200F, 747-400F, 747SR, and 747SP series 
airplanes. That AD requires detailed and high-frequency eddy current 
(HFEC) inspections for cracks of each affected tension tie and of the 
surrounding structure, and related investigative and corrective actions 
if necessary. That AD resulted from a report of a crack in the tension 
tie at the body station (BS) 820 frame connection, and cracks found on 
the Boeing 747SR fatigue-test airplane in both the tension ties and 
frames at the tension tie to frame connections at BS 800, 820, and 840. 
We issued that AD to find and fix cracks in the tension ties, which 
could lead to cracks in the skin and body frame and result in rapid in-
flight depressurization of the airplane.

Actions Since Existing AD Was Issued

    The preamble to AD 2006-01-07, Amendment 39 14446 (71 FR 1947, 
January 12, 2006), specifies that we consider the requirements to be 
``interim action'' and that the manufacturer was developing a 
modification to address the unsafe condition. That AD explains that we 
might consider further rulemaking if a

[[Page 58723]]

modification is developed, approved, and available. The manufacturer 
now has developed such a modification, and we have determined that 
further rulemaking is indeed necessary; this proposed AD follows from 
that determination.
    This proposed AD also results from reports of cracks on the forward 
and aft tension tie channels at station (STA) 740 and STA 760 on a 
Model 747-400F airplane, and a determination that initial inspection 
compliance times need to be reduced.

Relevant Service Information

    AD 2006-01-07, Amendment 39-14446 (71 FR 1947, January 12, 2006), 
refers to Boeing Special Attention Service Bulletin 747-53-2502, dated 
April 21, 2005, as the appropriate source of service information for 
doing the required actions. We have reviewed Boeing Alert Service 
Bulletin 747-53A2502, Revision 1, dated June 17, 2010. For Group 2 
airplanes, Boeing Alert Service Bulletin 747-53A2502, Revision 1, dated 
June 17, 2010, reduces the compliance time for the detailed and HFEC 
inspections of the tension ties; adds a one-time general visual 
inspection of the tension ties for correct configuration; adds a 
detailed and open fastener-hole HFEC inspection for cracks in the 
tension tie and frame if an incorrect configuration is found; and adds 
repair of the cracked tension tie, or instructions to contact Boeing 
for repair instructions.
    We have also reviewed Boeing Alert Service Bulletin 747-53A2605, 
Revision 1, dated May 27, 2010, which is not applicable to Model 747SP 
airplanes. Boeing Alert Service Bulletin 747-53A2605, Revision 1, dated 
May 27, 2010, describes procedures for modification of the left- and 
right-side tension tie structure or tension tie and frame structure at 
certain body stations, repetitive inspections of the modified area, 
repetitive detailed inspections for cracks on the unmodified area of 
the tension tie, and repair if necessary.

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 2006-01-07, Amendment 39-14446 (71 FR 1947, January 
12, 2006), and would retain the requirements of the existing AD with a 
reduced compliance time for certain airplanes. This proposed AD would 
also require accomplishing the actions specified in Boeing Alert 
Service Bulletin 747-53A2502, Revision 1, dated June 17, 2010; and 
Boeing Alert Service Bulletin 747-53A2605, Revision 1, dated May 27, 
2010; as described previously. Doing the modification specified in this 
proposed AD ends the existing repetitive inspections in the existing 
AD.

No Repetitive Intervals for Post-Modification Inspections of the 
Modified Areas

    Boeing Alert Service Bulletin 747-53A2605, Revision 1, dated May 
27, 2010, specifies to contact Boeing for the intervals for the 
repetitive post-modification inspections of the modified areas, nor 
does this proposed AD include those intervals. Post-modification 
inspection guidance for paragraph (j)(2) of this proposed AD may be 
defined in an approved alternative method of compliance (AMOC).

Changes to Existing AD

    In this NPRM, we have identified the legal name of the manufacturer 
as published in the most recent type certificate data sheet for the 
affected airplane models.
    Boeing Commercial Airplanes has received an Organization 
Designation Authorization (ODA), which replaces the previous 
designation as a Delegation Option Authorization (DOA) holder. We have 
revised paragraph (n) of this proposed AD to add delegation of 
authority to Boeing Commercial Airplanes ODA to approve an alternative 
method of compliance for certain repairs required by this AD.
    We have added a new paragraph (d) to this NPRM to provide the Air 
Transport Association (ATA) of America subject code 53: Fuselage. This 
code is added to make this proposed AD parallel with other new AD 
actions. We have re-identified subsequent paragraphs accordingly.

Differences Between the Proposed AD and the Service Information

    The service bulletins specify 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:
     In accordance with a method that we approve; or
     Using data that meet the certification basis of the 
airplane, and that have been approved by the Boeing Commercial 
Airplanes ODA whom we have authorized to make those findings.
    Boeing Alert Service Bulletin 747-53A2605, Revision 1, dated May 
27, 2010, includes a modification for all airplanes except for Model 
747SP airplanes. This proposed AD requires that modification for Model 
747SP airplanes.

Costs of Compliance

    There are about 276 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
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Average                                                   Number of
                                                               labor                                                      U.S.-
               Action                      Work hours         rate per           Parts            Cost per airplane    registered        Fleet cost
                                                                hour                                                    airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspection (required by AD 2006-01-  8 per tension tie             $85  $0....................  Between $5,440 and            141  Between $767,040 and
 07, Amendment 39-14446 (71 FR        location, between 8                                        $8,160 per                         $1,150,560 per
 1947, January 12, 2006)).            and 12 tension tie                                         inspection cycle.                  inspection cycle.
                                      locations per
                                      airplane, depending
                                      on airplane
                                      configuration.
One-time inspection (new proposed    6.....................         85  None..................  510..................          86  $43,860.
 action for Group 2 airplanes).
Modification (new proposed action).  Between 30 and 85,             85  Between $18,657 and     Between $21,207 and            86  Between $1,823,802
                                      depending on airplane              $635,004.               642,229.                           and $55,231,694.
                                      configuration.

[[Page 58724]]

 
Inspection for unmodified area.....  2 per tension tie              85  None..................  Between $1,360 and             86  Between $116,960 and
                                      location, between 8                                        $2,040.                            $175,440.
                                      and 12 tension tie
                                      locations per
                                      airplane, depending
                                      on airplane
                                      configuration.
Inspection for modified area.......  2 per tension tie              85  None..................  Between $1,360 and             86  Between $116,960 and
                                      location, between 8                                        $2,040.                            $175,440.
                                      and 12 tension tie
                                      locations per
                                      airplane, depending
                                      on airplane
                                      configuration.
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 affect intrastate aviation in Alaska, and
    (4) 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.

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.


Sec.  39.13  [Amended]

    2. The FAA amends Sec.  39.13 by removing Amendment 39-14446 (71 FR 
1947, January 12, 2006) and adding the following new AD:

The Boeing Company: Docket No. FAA-2011-0991; Directorate Identifier 
2010-NM-134-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by November 
7, 2011.

Affected ADs

    (b) This AD supersedes AD 2006-01-07, Amendment 39-14446 (71 FR 
1947, January 12, 2006).

Applicability

    (c) This AD applies to The Boeing Company Model 747-100, 747-
100B, 747-200B, 747-200C, 747-200F, 747-400F, 747SR, and 747SP 
series airplanes, certificated in any category, as identified in 
Boeing Alert Service Bulletin 747-53A2502, Revision 1, dated June 
17, 2010.

Subject

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

Unsafe Condition

    (e) This proposed AD results from reports that certain airplanes 
have tension ties that are susceptible to widespread fatigue damage. 
This proposed AD also results from reports of cracks on the forward 
and aft tension tie channels at station (STA) 740 and STA 760, and a 
determination that initial inspection compliance times need to be 
reduced. The Federal Aviation Administration is issuing this AD to 
prevent tension ties from becoming severed or disconnected from the 
frames, which could lead to rapid in-flight decompression.

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.

Restatement of Requirements of AD 2006-01-07, Amendment 39-14446 (71 FR 
1947, January 12, 2006), With Reduced Compliance Time for Certain 
Airplanes

Repetitive Inspections and Corrective Actions

    (g) For Group 1, and Groups 3 through 6 airplanes identified in 
Boeing Special Attention Service Bulletin 747-53-2502, dated April 
21, 2005; at the applicable time in paragraph (g)(1) or (g)(2) of 
this AD: Do detailed and high-frequency eddy current inspections for 
cracking of each affected tension tie and of the surrounding 
structure. If any cracking is found: Before further flight, do all 
applicable corrective and related investigative actions. Do all 
actions in accordance with the Accomplishment Instructions of Boeing 
Special Attention Service Bulletin 747-53-2502, dated April 21, 
2005; or Boeing Alert Service Bulletin 747-53A2502, Revision 1, 
dated June 17, 2010. Where Boeing Special Attention Service Bulletin 
747-53-2502, dated April 21, 2005; or Boeing Alert Service Bulletin 
747-53A2502, Revision 1, dated June 17, 2010; specifies to contact 
Boeing for repair instructions: Before further flight, repair the 
area using a method approved in accordance with paragraph (n) of 
this AD. As of the effective date of this AD, only Boeing Alert 
Service Bulletin 747-53A2502, Revision 1,

[[Page 58725]]

dated June 17, 2010, may be used for the actions required in this 
paragraph.
    (1) For airplanes identified in Boeing Special Attention Service 
Bulletin 747-53-2502, dated April 21, 2005, as Groups 1, 3, and 6 
airplanes: Do the first inspections before the accumulation of 
20,000 total flight cycles, or within 1,000 flight cycles after 
February 16, 2006 (the effective date of AD 2006-01-07, Amendment 
39-14446 (71 FR 1947, January 12, 2006)), whichever occurs later; 
and repeat the inspections thereafter at intervals not to exceed 
4,000 flight cycles until the modification required by paragraph (j) 
of this AD is accomplished.
    (2) For airplanes identified in Boeing Special Attention Service 
Bulletin 747-53-2502, dated April 21, 2005, as Group 4 and 5 
airplanes: Do the first inspections before the accumulation of 
17,000 total flight cycles, or within 1,000 flight cycles after 
February 16, 2006, whichever occurs later; and repeat the 
inspections thereafter at intervals not to exceed 3,000 flight 
cycles until the modification required by paragraph (j) of this AD 
is accomplished.

Inspection for Group 2 Airplanes With Reduced Compliance Times

    (h) For Group 2 airplanes identified in Boeing Alert Service 
Bulletin 747-53A2502, Revision 1, dated June 17, 2010: At the 
applicable times specified in paragraphs (h)(1) and (h)(2) of this 
AD, do detailed and high-frequency eddy current inspections for 
cracking of each affected tension tie and of the surrounding 
structure, in accordance with the Accomplishment Instructions of 
Boeing Special Attention Service Bulletin 747-53-2502, dated April 
21, 2005; or Boeing Alert Service Bulletin 747-53A2502, Revision 1, 
dated June 17, 2010. If any cracking is found: Before further 
flight, do all applicable corrective and related investigative 
actions. Do all actions in accordance with the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 747-53-
2502, dated April 21, 2005; or Boeing Alert Service Bulletin 747-
53A2502, Revision 1, dated June 17, 2010. Where Boeing Special 
Attention Service Bulletin 747-53-2502, dated April 21, 2005; or 
Boeing Alert Service Bulletin 747-53A2502, Revision 1, dated June 
17, 2010; specify to contact Boeing for repair instructions: Before 
further flight, repair the area using a method approved in 
accordance with paragraph (n) of this AD. As of the effective date 
of this AD, only Boeing Alert Service Bulletin 747-53A2502, Revision 
1, dated June 17, 2010, may be used. Repeat the inspections 
thereafter at intervals not to exceed 3,000 flight cycles until the 
modification required by paragraph (j) of this AD is accomplished.
    (1) For STA 780 through 940: Before the accumulation of 17,000 
total flight cycles, or within 1,000 flight cycles after February 
16, 2006, whichever occurs later.
    (2) For STA 720, 740, and 760: At the earlier of the times of 
paragraph (h)(2)(i) or (h)(2)(ii).
    (i) Before the accumulation of 17,000 total flight cycles, or 
within 1,000 flight cycles after February 16, 2006, whichever occurs 
later.
    (ii) Before the accumulation of 8,000 total flight cycles, or 
within 1,000 flight cycles after the effective date of this AD, 
whichever occurs later.

New Requirements of This AD

One-Time Inspection for Group 2 Airplanes

    (i) For airplanes identified in Boeing Alert Service Bulletin 
747-53A2502, Revision 1, dated June 17, 2010, as Group 2 airplanes: 
Before the accumulation of 8,000 total flight cycles, or within 
1,000 flight cycles after the effective date of this AD, whichever 
occurs later: Do a general visual inspection for correct 
configuration, as identified in Boeing Alert Service Bulletin 747-
53A2502, Revision 1, dated June 17, 2010, of each affected tension 
tie and of the surrounding structure, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2502, Revision 1, dated June 17, 2010.
    (1) If all tension ties match the correct configurations 
specified in the Accomplishment Instructions of Boeing Alert Service 
Bulletin 747-53A2502, Revision 1, dated June 17, 2010, no further 
work is required by this paragraph.
    (2) If any incorrect configuration is found, before further 
flight, do detailed and open fastener-hole HFEC inspections for 
cracks in the tension tie and frame, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2502, Revision 1, dated June 17, 2010.
    (i) If no crack is found during the inspection required by 
paragraph (i)(2) of this AD, before further flight, install the 
correct configuration for the tension ties at locations where the 
incorrect configuration was found, using a method approved in 
accordance with the procedures specified in paragraph (n) of this 
AD.
    (ii) If any crack is found during the inspection required by 
paragraph (i)(2) of this AD, before further flight, do the actions 
in paragraphs (i)(2)(ii)(A) and (i)(2)(ii)(B) of this AD.
    (A) Repair the crack in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-53A2502, Revision 
1, dated June 17, 2010, except where Boeing Alert Service Bulletin 
747-53A2502, Revision 1, dated June 17, 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 (n) of this AD.
    (B) Install the correct configuration for the tension ties at 
locations where the incorrect configuration was found, using a 
method approved in accordance with the procedures specified in 
paragraph (n) of this AD.

Modification

    (j) Before the accumulation of 30,000 total flight cycles, or 
within 3,000 flight cycles after the effective date of this AD, 
whichever occurs later, modify the left- and right-side tension tie 
structure or left- and right-side tension tie and frame structure, 
at specified stations, in accordance with the applicable method 
specified in paragraph (j)(1) or (j)(2) of this AD. Accomplishment 
of the modification in this paragraph terminates the repetitive 
inspection requirements in paragraphs (g)(1), (g)(2), and (h) of 
this AD.
    (1) For airplanes identified in Boeing Alert Service Bulletin 
747-53A2605, Revision 1, dated May 27, 2010: Do the modification, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 747-53A2605, Revision 1, dated May 27, 2010.
    (2) For airplanes not identified in Boeing Alert Service 
Bulletin 747-53A2605, Revision 1, dated May 27, 2010: Do the 
modification, using a method approved in accordance with paragraph 
(n) of this AD.

    Note 1: For airplanes identified in paragraph (j)(2) of this AD, 
post-modification inspection guidance may be defined in an approved 
alternative method of compliance (AMOC) for paragraph (j)(2) of this 
AD.

Post-Modification Inspection of the Modified Areas

    (k) For airplanes identified in paragraph (j)(1) of this AD, 
within 20,000 flight cycles after doing the modification required by 
paragraph (j) of this AD, do an inspection for cracks of the 
modified areas of the left- and right-side tension tie structure and 
frame structure, in accordance with a method approved with the 
procedures specified in paragraph (n) of this AD. If any crack is 
found during any inspection required by this paragraph, before 
further flight, repair the crack using a method approved in 
accordance with the procedures specified in paragraph (n) of this 
AD.

Post-Modification Repetitive Inspections of the Unmodified Areas

    (l) For airplanes identified in paragraph (j)(1) of this AD, 
within 6,000 flight cycles after doing the modification required by 
paragraph (j) of this AD, do a detailed inspection for cracks on the 
unmodified areas of the left- and right-side tension tie structure 
and frame structure, at certain stations, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2605, Revision 1, dated May 27, 2010. If any crack is found 
during any inspection required by this paragraph, before further 
flight, repair the crack using a method approved in accordance with 
the procedures specified in paragraph (n) of this AD. Repeat the 
inspection of the unmodified areas thereafter at intervals not to 
exceed 6,000 flight cycles.

    Note 2: Boeing Alert Service Bulletin 747-53A2605, Revision 1, 
dated May 27, 2010, refers to Section 51-10-02 of the Boeing 747-
400F Structural Repair Manual (SRM) and Section 51-10-01 of the 
Boeing 747-100/200/300 SRM as additional sources of guidance for 
removing small cracks and fatigue damage material from the existing 
holes in the unmodified center section of the tension tie channels. 
Where those SRM sections state that ``zero-timing must only be used 
where specifically permitted in an SRM chapter-section-repair,'' 
this AD allows the zero-timing procedures specified in those SRM 
sections.

Credit for Actions Accomplished in Accordance With Previous Service 
Information

    (m) Actions done in accordance with Boeing Alert Service 
Bulletin 747-53A2605,

[[Page 58726]]

dated October 8, 2009, before the effective date of this AD are 
acceptable for compliance with the corresponding actions required by 
paragraphs (j), (k), and (l) of this AD.

Alternative Methods of Compliance (AMOCs)

    (n)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. In accordance with 14 
CFR 39.19, send your request to your principal inspector or local 
Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in the Related Information 
section of this AD. Information may be e-mailed to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD if it is approved by the 
Boeing Commercial Airplanes Organization Designation Authorization 
(ODA) that 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.
    (4) Certain actions required by paragraph (g) of this AD are 
approved as AMOCs for the requirements specified in paragraphs 
(n)(4)(i), (n)(4)(ii), and (n)(4)(iii) of this AD. All provisions of 
the referenced ADs in paragraphs (n)(4)(i), (n)(4)(ii), and 
(n)(4)(iii) of this AD, including applicable post-modification 
inspection thresholds, remain fully applicable and must be complied 
with.
    (i) Repairs or modifications of the aft tension tie channels 
done in accordance with this AD are AMOCs for the repair 
requirements of paragraph A. of AD 84-19-01, Amendment 39-4913 (49 
FR 35365, September 17, 1984), and paragraphs (a)(2) and (b)(2) of 
AD 94-13-06, Amendment 39-8946 (59 FR 32879, June 27, 1994).
    (ii) The inspection requirements of this AD are AMOCs for the 
post-modification inspection requirements of paragraph B. of AD 84-
19-01, Amendment 39-4913 (49 FR 35365, September 17, 1984), and 
paragraph (b) of AD 94-13-06, Amendment 39-8946 (59 FR 32879, June 
27, 1994).
    (iii) The inspection requirements of this AD are AMOCs for the 
inspections of Structural Significant Item (SSI) F-19A of Boeing 
Supplemental Structural Inspection Document D6-35022, Revision G, 
dated December 2000, as required by paragraphs (h) and (i) of AD 
2004-07-22 R1, Amendment 39-15326 (73 FR 1052, January 7, 2008), 
corrected on February 14, 2008 (73 FR 8589).

Related Information

    (o) For more information about this AD, contact Steven Fox, 
Senior Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle 
ACO, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone 
(425) 917-6425; fax (425) 917-6590; e-mail: [email protected].
    (p) 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 
206-544-5000, extension 1; fax 206-766-5680; e-mail 
[email protected]; 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.

    Issued in Renton, Washington, on September 14, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-24356 Filed 9-21-11; 8:45 am]
BILLING CODE 4910-13-P