
[Federal Register Volume 78, Number 106 (Monday, June 3, 2013)]
[Proposed Rules]
[Pages 33012-33015]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-13002]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0461; Directorate Identifier 2012-NM-169-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede an existing airworthiness directive 
(AD) that applies to certain The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 
747SR, and 747SP series airplanes. The existing AD currently requires 
repetitive inspections for skin cracks at the shear tie end fastener 
locations of the fuselage frames, and repairing cracks if necessary. 
Since we issued that AD, additional cracking has been found on an 
airplane not affected by the existing AD. This proposed AD would also 
require repetitively inspecting for skin cracks next to the shear tie 
on airplanes with certain existing repair doublers, and corrective 
actions if necessary. This proposed AD would also revise the 
applicability to include additional airplanes. We are proposing this AD 
to detect and correct fatigue cracks in the fuselage skin that can 
propagate and grow, and result in reduced structural integrity and 
sudden decompression of the airplane in flight.

DATES: We must receive comments on this proposed AD by July 18, 2013.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, 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: Deliver to Mail address above 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, WA 98124-2207; telephone 206-544-5000, 
extension 1; fax 206-766-5680; 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 (phone: 800-647-5527) is in the ADDRESSES 
section. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Roger Caldwell, Aerospace Engineer, 
Technical Operations Center, ANM-100D, FAA, Denver Aircraft 
Certification Office (ACO), 26805 East 68th Avenue, Room 214, Denver, 
Colorado 80249-6361; phone: 303-342-1086; fax: 303-342-1088; email: 
roger.caldwell@faa.gov.

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-2013-0461; 
Directorate Identifier 2012-NM-169-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 February 27, 2009, we issued AD 2009-06-02, Amendment 39-15838 
(74 FR 11013, March 16, 2009), for certain The Boeing Company Model 
747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 
747-400, 747SR, and 747SP series airplanes.

[[Page 33013]]

That AD requires inspecting for skin cracks at the shear tie end 
fastener locations of the fuselage frames, and repairing cracks if 
necessary. That AD resulted from a widespread fatigue damage (WFD) 
assessment of Model 747 airplanes. We issued that AD to detect and 
correct cracks in the fuselage skin that can propagate and grow, 
resulting in a loss of structural integrity and sudden decompression of 
the airplane during flight.

WFD Program

    Structural fatigue damage is progressive. It begins as minute 
cracks, and those cracks grow under the action of repeated stresses. 
This can happen because of normal operational conditions and design 
attributes, or because of isolated situations or incidents such as 
material defects, poor fabrication quality, or corrosion pits, dings, 
or scratches. Fatigue damage can occur locally, in small areas or 
structural design details, or globally. Global fatigue damage is 
general degradation of large areas of structure with similar structural 
details and stress levels. Multiple-site damage is global damage that 
occurs in a large structural element such as a single rivet line of a 
lap splice joining two large skin panels. Global damage can also occur 
in multiple elements such as adjacent frames or stringers. Multiple-
site-damage and multiple-element-damage cracks are typically too small 
initially to be reliably detected with normal inspection methods. 
Without intervention, these cracks will grow, and eventually compromise 
the structural integrity of the airplane, in a condition known as 
widespread fatigue damage (WFD). As an airplane ages, WFD will likely 
occur, and will certainly occur if the airplane is operated long enough 
without any intervention.
    The FAA's WFD final rule (75 FR 69746, November 15, 2010) became 
effective on January 14, 2011. The WFD rule requires certain actions to 
prevent structural failure due to WFD throughout the operational life 
of certain existing transport category airplanes and all of these 
airplanes that will be certificated in the future. For existing and 
future airplanes subject to the WFD rule, the rule requires that design 
approval holders (DAHs) and applicants establish a limit of validity 
(LOV) of the engineering data that support the structural maintenance 
program. Operators affected by the WFD rule may not fly an airplane 
beyond its LOV, unless an extended LOV is approved.
    The WFD rule does not require identifying and developing 
maintenance actions if the DAHs can show that such actions are not 
necessary to prevent WFD before the airplane reaches the LOV. Many 
LOVs, however, do depend on accomplishment of future maintenance 
actions. As stated in the WFD rule, any maintenance actions necessary 
to reach the LOV will be mandated by airworthiness directives through 
separate rulemaking actions.
    In the context of WFD, this action is necessary to enable DAHs to 
propose LOVs that allow operators the longest operational lives for 
their airplanes, and still ensure that WFD will not occur. This 
approach allows for an implementation strategy that provides 
flexibility to DAHs in determining the timing of service information 
development (with FAA approval), while providing operators with 
certainty regarding the LOV applicable to their airplanes.
    Fuselage frame shear ties, located between longitudinal stringers, 
are an integral part of the load-bearing airframe structure. Cracks in 
the skin at fuselage frame shear tie end fastener locations, if not 
corrected, could result in cracks in the fuselage skin, which can 
propagate and become large, and result in loss of structural integrity 
and sudden decompression of the airplane in flight.

Actions Since Existing AD (AD 2009-06-02, Amendment 39-15838 (74 FR 
11013, March 16, 2009)) Was Issued

    Since we issued AD 2009-06-02, Amendment 39-15838 (74 FR 11013, 
March 16, 2009), we have received a report indicating that three skin 
cracks were found on one airplane at fastener holes common to the 
station (STA) 540 frame shear tie between stringer 23L and stringer 
25L. The affected airplane had T-shaped shear ties in the area of the 
inspection required by AD 2009-06-02, but was not included in the 
applicability. Based on the reports of cracks in T-shaped shear ties, 
we have determined that the unsafe condition may exist on additional 
airplanes, including airplane line numbers 758 through 1419 inclusive 
(except large cargo freighter airplanes).
    It has also been determined that post-repair inspections of certain 
existing repair doublers are necessary.

Relevant Service Information

    We reviewed Boeing Alert Service Bulletin 747-53A2682, Revision 1, 
dated May 24, 2012. For information on the procedures and compliance 
times, see this service information at http://www.regulations.gov by 
searching for Docket No. FAA-2013-0461.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    Although this proposed AD does not explicitly restate the 
requirements of AD 2009-06-02, Amendment 39-15838 (74 FR 11013, March 
16, 2009), this proposed AD would retain all of the requirements of AD 
2009-06-02. Those requirements are referenced in the service 
information identified previously, which, in turn, is referenced in 
paragraph (g) of this proposed AD. This proposed AD would also require 
repetitively inspecting for skin cracks next to the shear tie on 
airplanes with certain existing doublers, and corrective action if 
necessary. This proposed AD would also revise the applicability to 
include additional airplanes. This proposed AD would require 
accomplishing the actions specified in the service information 
described previously.
    This proposed AD would also require that requests for approval of 
alternative methods of compliance (AMOCs) be directed to the Seattle 
Aircraft Certification Office.
    The phrase ``corrective actions'' is used in this proposed AD. 
``Corrective actions'' are actions that correct or address any 
condition found. Corrective actions in an AD could include, for 
example, repairs.

Difference Between Proposed AD and Service Information

    The service bulletin 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:
     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 Organization Designation Authorization (ODA) whom we have 
authorized to make those findings.

Costs of Compliance

    We estimate that this proposed AD affects 234 airplanes of U.S. 
registry. We estimate the following costs to comply with this proposed 
AD:

[[Page 33014]]



                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                Cost on U.S.
           Action                  Labor cost         Parts cost       Cost per product          operators
----------------------------------------------------------------------------------------------------------------
Inspection.................  30 or 49 work-hours                $0  $2,550 or $4,165 per   Up to $974,610 per
                              (depending on                          inspection cycle.      inspection cycle.
                              inspection) x $85
                              per hour = $2,550 or
                              $4,165 per
                              inspection cycle.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this proposed 
AD.

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),
    (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

0
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]

0
2. The FAA amends Sec.  39.13 by removing airworthiness directive (AD) 
2009-06-02, Amendment 39-15838 (74 FR 11013, March 16, 2009), and 
adding the following new AD:

The Boeing Company: Docket No. FAA-2013-0461; Directorate Identifier 
2012-NM-169-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by July 18, 
2013.

(b) Affected ADs

    This AD supersedes AD 2009-06-02, Amendment 39-15838 (74 FR 
11013, March 16, 2009).

(c) Applicability

    This AD applies to 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, as identified in 
Boeing Alert Service Bulletin 747-53A2682, Revision 1, dated May 24, 
2012.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 53, Fuselage.

(e) Unsafe Condition

    This AD was prompted by an evaluation by the design approval 
holder (DAH) indicating that certain fuselage frame shear ties are 
subject to widespread fatigue damage (WFD). The actions were 
developed to support the airplane's limit of validity (LOV) of the 
engineering data that support the established structural maintenance 
program. We are issuing this AD to detect and correct fatigue cracks 
in the fuselage skin that can propagate and grow, and result in 
reduced structural integrity and sudden decompression of the 
airplane in flight.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Repetitive Inspections

    At the applicable compliance time specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 747-53A2682, 
Revision 1, dated May 24, 2012, except as provided by paragraphs 
(i)(1) and (i)(2) of this AD, do an external detailed or high 
frequency eddy current (HFEC) inspection for skin cracks at 
specified shear tie end fastener locations of the fuselage frames, 
and do all applicable corrective actions, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2682, Revision 1, dated May 24, 2012, except as required by 
paragraph (i)(3) of this AD. Do all applicable corrective actions 
before further flight. Repeat the external detailed or HFEC 
inspection thereafter at the applicable time specified in paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 747-53A2682, 
Revision 1, dated May 24, 2012.

(h) Post-Repair Inspections

    For any external repair doubler in the inspection area specified 
in the Accomplishment Instructions of Boeing Alert Service Bulletin 
747-53A2682, Revision 1, dated May 24, 2012, that has an upper or 
lower fastener row that is common to a shear tie end fastener: At 
the applicable time specified in paragraph (h)(1) or (h)(2) of this 
AD, whichever occurs later, do an internal HFEC inspection for 
cracks in the skin next to the shear tie, and do all applicable 
corrective actions, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-53A2682, Revision 
1, dated May 24, 2012, except as required by paragraph (i)(3) of 
this AD. Do all corrective actions before further flight. Repeat the 
external detailed inspection thereafter at the time specified in 
Table 4 or Table 5 of paragraph 1.E., ``Compliance,'' of Boeing 
Alert Service Bulletin 747-53A2682, Revision 1, dated May 24, 2012, 
as applicable.
    (1) Before further flight after an inspection required by 
paragraph (g) of this AD.
    (2) Within 2,000 flight cycles after the effective date of this 
AD.

(i) Service Information Clarifications and Exceptions

    (1) Paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 747-53A2682, Revision 1, dated May 24, 2012, specifies 
certain compliance times in terms of the effective date of AD 2009-
06-02,

[[Page 33015]]

Amendment 39-15838 (74 FR 11013, March 16, 2009). The effective date 
of AD 2009-06-02 is April 20, 2009.
    (2) Where paragraph 1.E. of Boeing Alert Service Bulletin 747-
53A2682, Revision 1, dated May 24, 2012, specifies counting the 
compliance time ``after the revision 1 date of this service 
bulletin,'' this AD requires compliance within the applicable time 
after the effective date of this AD.
    (3) Where Boeing Alert Service Bulletin 747-53A2682, Revision 1, 
dated May 24, 2012, specifies to contact Boeing for repair 
instructions, this AD requires repair before further flight using a 
method approved in accordance with the procedures specified in 
paragraph (l) of this AD.

(j) Credit for Previous Actions

    This paragraph provides credit for the actions specified in 
paragraph (g) of this AD, if those actions were performed before the 
effective date of this AD using Boeing Alert Service Bulletin 747-
53A2682, dated May 8, 2008.

(k) Special Flight Permit

    Special flight permits, as described in Section 21.197 and 
Section 21.199 of the Federal Aviation Regulations (14 CFR 21.197 
and 21.199), are not allowed.

(l) Alternative Methods of Compliance (AMOCs)

    (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 paragraph (m)(2) of this AD. 
Information may be emailed to: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (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.

(m) Related Information

    (1) For more information about this AD, contact Roger Caldwell, 
Aerospace Engineer, Technical Operations Center, ANM-100D, FAA, 
Denver ACO, 26805 East 68th Avenue, Room 214, Denver, Colorado 
80249-6361; phone: 303-342-1086; fax: 303-342-1088; email: 
roger.caldwell@faa.gov.
    (2) For information about AMOCs, contact Bill Ashforth, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 
1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 425-917-
6432; fax: 425-917-6590; email: bill.ashforth@faa.gov.
    (3) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; 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 May 22, 2013.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-13002 Filed 5-31-13; 8:45 am]
BILLING CODE 4910-13-P


