[Federal Register Volume 78, Number 155 (Monday, August 12, 2013)]
[Proposed Rules]
[Pages 48835-48838]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-19462]



[[Page 48835]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0686; Directorate Identifier 2013-NM-006-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 airworthiness directive (AD) 2007-16-
19, which applies to certain The Boeing Company Model 747-200B, 747-
300, and 747-400 series airplanes. AD 2007-16-19 requires repetitive 
detailed inspections for cracking of the aft tension tie channels from 
body station (BS) 1120 to BS 1220 and from BS 880 to BS 1100, and 
corrective actions if necessary, and optional terminating action. Since 
we issued that AD, analysis has indicated the need to mandate the 
previously optional modification. This proposed AD would retain the 
existing requirements, limit the area of the detailed inspection, add 
repetitive surface high-frequency eddy current inspections, and mandate 
the previously optional terminating action. We are proposing this AD to 
prevent fatigue cracking of the tension ties, which could result in 
reduced structural integrity of the airplane and rapid depressurization 
of the airplane.

DATES: We must receive comments on this proposed AD by September 26, 
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 proposed 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, WA. 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: Bill Ashforth, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 425-
917-6432; fax: 425-917-6590; email: [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-2013-0686; 
Directorate Identifier 2013-NM-006-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 August 2, 2007, we issued AD 2007-16-19, Amendment 39-15158 (72 
FR 45151, August 13, 2007), for certain The Boeing Company Model 747-
200B, 747-300, and 747-400 series airplanes. AD 2007-16-19 requires 
repetitive detailed inspections for cracking of the aft tension tie 
channels from body station (BS) 1120 to BS 1220 and from BS 880 to BS 
1100, and corrective actions if necessary. AD 2007-16-19 was prompted 
by cracks found in the aft tension tie channels at four station 
locations on a Model 747-200B series airplane that had been modified to 
a special freighter. We issued AD 2007-16-19 to detect and correct 
cracking of the aft tension tie channels; failure of more than one 
tension tie could result in rapid depressurization of the airplane.

WFD (Widespread Fatigue Damage) 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 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.

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    The WFD rule (75 FR 69746, November 15, 2010) 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.

Actions Since AD 2007-16-19, Amendment 39-15158 (72 FR 45151, August 
13, 2007) Was Issued

    AD 2007-16-19, Amendment 39-15158 (72 FR 45151, August 13, 2007), 
provides a terminating modification as an option. We have determined 
that it is necessary to mandate this modification to adequately address 
the identified unsafe condition. We can better ensure long-term 
continued operational safety by design changes to remove the source of 
the problem, rather than by repetitive inspections. Long-term 
inspections may not provide the degree of safety necessary for the 
transport airplane fleet. This determination, along with a better 
understanding of the human factors associated with numerous continual 
inspections, has led us to consider placing less emphasis on 
inspections and more emphasis on design improvements. The proposed 
modification requirement is consistent with these conditions.

Relevant Service Information

    We reviewed Boeing Alert Service Bulletin 747-53A2610, Revision 1, 
dated December 4, 2012. For information on the procedures and 
compliance times, see this service information at http://www.regulations.gov by searching for Docket No. FAA-2013-0686.

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 2007-16-19, Amendment 39-15158 (72 FR 45151, August 
13, 2007), this proposed AD would retain all of the requirements of AD 
2007-16-19. Those requirements are referenced in the service 
information identified previously, which, in turn, is referenced in 
paragraph (g) of this proposed AD. Also, this proposed AD would limit 
the area of the existing detailed inspection required by AD 2007-16-19, 
add repetitive surface high-frequency eddy current inspections, and 
mandate the previously optional terminating action.
    The phrase ``related investigative actions'' is used in this 
proposed AD. ``Related investigative actions'' are follow-on actions 
that (1) are related to the primary actions, and (2) further 
investigate the nature of any condition found. Related investigative 
actions in an AD could include, for example, inspections.
    In addition, 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

    Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated 
December 4, 2012, 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 1 airplane of U.S. 
registry. We estimate the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
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                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Retained detailed inspection       4 work-hours x $85               $0  $340 per inspection  $340 per inspection
 (retained actions.                 per hour = $340                      cycle.               cycle.
                                    per inspection
                                    cycle.
New proposed surface high-         4 work-hours x $85                0  $340 per inspection  $340 per inspection
 frequency eddy current             per hour = $340                      cycle.               cycle.
 inspection.                        per inspection
                                    cycle.
New proposed modification........  64 work-hours x $85          14,948  $20,388............  $20,388.
                                    per hour = $5,440.
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    We have received no definitive data that would enable us to provide 
work-hour estimates for repair of cracks found in a bolt hole during 
the detailed inspection specified in this proposed AD. The cost for 
parts (oversized fastener kit) for this condition is $2,292.

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

[[Page 48837]]

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) 
2007-16-19, Amendment 39-15158 (72 FR 45151, August 13, 2007), and 
adding the following new AD:

The Boeing Company: Docket No. FAA-2013-0686; Directorate Identifier 
2013-NM-006-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by September 26, 
2013.

(b) Affected ADs

    This AD supersedes AD 2007-16-19, Amendment 39-15158 (72 FR 
45151, August 13, 2007). Certain requirements of AD 2012-15-13, 
Amendment 39-17142 (77 FR 47267, August 8, 2012), affect certain 
requirements of this AD.

(c) Applicability

    This AD applies to The Boeing Company Model 747-200B, 747-300, 
and 747-400 series airplanes, certificated in any category, as 
identified in Boeing Alert Service Bulletin 747-53A2610, Revision 1, 
dated December 4, 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 the tension ties are subject to 
widespread fatigue damage (WFD). We are issuing this AD to prevent 
fatigue cracking of the tension ties, which could result in reduced 
structural integrity of the airplane and rapid depressurization of 
the airplane.

(f) Compliance

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

(g) Repetitive Inspections

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 747-53A2610, 
Revision 1, dated December 4, 2012, except as specified in paragraph 
(i) of this AD: Do detailed and surface high-frequency eddy current 
inspections for cracks in the tension ties at body stations (STAs) 
880 to 1100, 1120, 1160, 1200, and 1220, and do all applicable 
corrective actions, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-53A2610, Revision 
1, dated December 4, 2012, except as required by paragraph (i)(3) of 
this AD. Do all applicable corrective actions before further flight. 
Repeat the inspections thereafter at the applicable time specified 
in paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
747-53A2610, Revision 1, dated December 4, 2012, until the tension 
ties have been modified as required by paragraph (h) of this AD. 
Repair or modification of a tension tie at any location in 
accordance with Part 3 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 
2012, terminates the repetitive inspection requirements of this AD 
for that tension tie location only.

(h) Tension Tie Modification

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 747-53A2610, 
Revision 1, dated December 4, 2012, except as specified in paragraph 
(i) of this AD: Modify the tension ties from STA 880 to 1100, and do 
all applicable related investigative and corrective actions, in 
accordance with Part 3 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 747-53A2610, Revision 1, dated December 4, 
2012, except as required by paragraph (i)(3) of this AD. Do all 
applicable related investigative and corrective actions before 
further flight. Modification of all tension ties at the body 
stations specified in Part 3 of the Accomplishment Instructions of 
Boeing Alert Service Bulletin 747-53A2610, Revision 1, dated 
December 4, 2012, terminates the repetitive inspection requirements 
of this AD. Modification of a tension tie at STA 1120 to 1220, as 
required by paragraph (p) of AD 2012-15-13, Amendment 39-17142 (77 
FR 47267, August 8, 2012), is acceptable for compliance with the 
requirements of paragraph (h) of this AD for that tension tie 
location only.

(i) Service Information Clarification and Exceptions

    (1) Paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 747-53A2610, Revision 1, dated December 4, 2012, specifies 
certain compliance times ``after August 28, 2007.'' August 28, 2007, 
is the effective date of AD 2007-16-19, Amendment 39-15158 (72 FR 
45151, August 13, 2007).
    (2) Where Boeing Alert Service Bulletin 747-53A2610, Revision 1, 
dated December 4, 2012, specifies a compliance time ``after the 
Revision 1 date of this service bulletin,'' this AD requires 
compliance within the specified time after the effective date of 
this AD.
    (3) Where Boeing Alert Service Bulletin 747-53A2610, Revision 1, 
dated December 4, 2012, specifies to contact Boeing for certain 
repair instructions: Repair before further flight using a method 
approved in accordance with the procedures specified in paragraph 
(k) of this AD.

(j) Credit for Previous Actions

    This paragraph provides credit for the detailed inspections, 
repairs, and modification specified in paragraphs (g) and (h) of 
this AD, for that affected tension tie location only, if those 
actions were performed before the effective date of this AD using 
Boeing Alert Service Bulletin 747-53A2610, dated May 10, 2007 (which 
is not incorporated by reference in this AD).

(k) 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 the Related Information 
section of this AD. Information may be emailed 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) AMOCs approved previously in accordance with AD 2007-16-19, 
Amendment 39-15158 (72 FR 45151, August 13, 2007), are approved as 
AMOCs for the corresponding provisions of this AD.

(l) Related Information

    (1) For more information about this AD, contact Bill Ashforth, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office (ACO), 1601 Lind Avenue SW., Renton, Washington 
98057-

[[Page 48838]]

3356; phone: 425-917-6432; fax: 425-917-6590; email: 
[email protected].
    (2) 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, WA. For information on the availability of 
this material at the FAA, call 425-227-1221.


    Issued in Renton, Washington, on August 1, 2013.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-19462 Filed 8-9-13; 8:45 am]
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