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[Federal Register Volume 78, Number 176 (Wednesday, September 11, 2013)]
[Proposed Rules]
[Pages 55662-55664]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-22147]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0706; Directorate Identifier 2013-NM-067-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 adopt a new airworthiness directive (AD) for 
certain the Boeing Company Model DC-9-10, DC-9-30, and DC-9-40 series 
airplanes. This proposed AD was prompted by an evaluation by the design 
approval holder (DAH) indicating that the aft pressure bulkhead web 
area is subject to widespread fatigue damage (WFD). This proposed AD 
would require modifying the aft pressure bulkhead. The modification 
includes inspecting for cracks around the rivet holes, and repair of 
any cracking. We are proposing this AD to prevent fatigue cracking of 
the aft pressure bulkhead, which could result in reduced structural 
integrity of the airplane.

DATES: We must receive comments on this proposed AD by October 28, 
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, 3855 
Lakewood Boulevard, MC D800-0019, Long Beach, CA 90846-0001; telephone 
206-544-5000, extension 2; fax 206-766-5683; 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: Eric Schrieber, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: (562) 
627-5348; fax: (562) 627-5210; email: eric.schrieber@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2013-0706; 
Directorate Identifier 2013-NM-067-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

    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 DAHs 
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 (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

[[Page 55663]]

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.

Explanation of Applicability

    For The Boeing Company Model DC-9 series airplanes, AD 85-01-02 R1, 
Amendment 39-5241 (51 FR 6101, dated February 20, 1988), was issued to 
supersede an AD that required visual, eddy current, and x-ray 
inspections of the aft pressure bulkhead for cracking. AD 85-01-02 R1 
required accomplishing the modification specified in Boeing Alert 
Service Bulletin DC9-A53-144, Revision 2, dated February 23, 1984, 
within 18 months after March 31, 1986 (the effective date of AD 85-01-
02 R1). Boeing Alert Service Bulletin DC9-A53-144, Revision 2, dated 
February 23, 1984, specifies that the modification must be done for 
Groups I and II airplanes with more than 40,000 total flight cycles.
    We are proposing this AD to address Group I or Group II airplanes 
that have not accomplished the modification specified in Boeing Alert 
Service Bulletin DC9-A53-144, Revision 2, dated February 23, 1984. This 
proposed AD is not a supersedure because the required actions apply 
only to those airplanes. AD 85-01-02 R1, Amendment 39-5241 (51 FR 6101, 
dated February 20, 1988), also contained additional actions that are 
not included in this proposed AD.

Relevant Service Information

    We reviewed Boeing Alert Service Bulletin DC9-A53-144, Revision 2, 
dated February 23, 1984. For information on the procedures and 
compliance times, see this service information at http://www.regulations.gov by searching for Docket No. FAA-2013-0706.

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

    This proposed AD would require accomplishing the actions specified 
in the service information identified previously, except as discussed 
under ``Differences Between the Proposed AD and the Service 
Information.''

Differences Between the Proposed AD and the Service Information

    Boeing Alert Service Bulletin DC9-A53-144, Revision 2, dated 
February 23, 1984, specifies that the original ventral bulkhead was 
tested by McDonnell Douglas for up to 76,550 flight cycles, and 
cracking was detected at 72,000 flight cycles. It was determined that 
the initial inspection threshold of 40,000 flight cycles, as specified 
in the service information, was based on half the test life, which was 
adjusted for the current fleet distribution at that time. Testing also 
showed an onset of cracking at 72,000 flight cycles was not widespread 
fatigue type cracking. Therefore, we have determined that a compliance 
time of ``before the accumulation of 72,000 flight cycles or with 18 
months after the effective date of the AD, whichever is later'' 
adequately addresses the unsafe condition identified in this proposed 
AD.
    Sheet 1 of Service Sketch 3109, and Sheet 7 of Service Sketch 3110B 
of Boeing Alert Service Bulletin DC9-A53-144, Revision 2, dated 
February 23, 1984; specify reporting the details of any cracks found; 
however, this proposed AD does not require reporting.
    Boeing Alert Service Bulletin DC9-A53-144, Revision 2, dated 
February 23, 1984, 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.
    These differences have been coordinated with the manufacturer.

Explanation of Compliance Time

    The compliance time for the modification specified in this proposed 
AD for addressing WFD was established to ensure that discrepant 
structure is modified before WFD develops in airplanes. Standard 
inspection techniques cannot be relied on to detect WFD before it 
becomes a hazard to flight. We will not grant any extensions of the 
compliance time to complete any AD-mandated service bulletin related to 
WFD without extensive new data that would substantiate and clearly 
warrant such an extension.

Costs of Compliance

    We estimate that this proposed AD affects 6 airplanes 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
----------------------------------------------------------------------------------------------------------------
Modification (includes           542 work-hours x $85              $4,680            $50,750           $304,500
 inspection).                     per hour = $46,070.
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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.

[[Page 55664]]

Regulatory Findings

    We 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 this 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 adding the following new airworthiness 
directive (AD):

The Boeing Company: Docket No. FAA-2013-0706; Directorate Identifier 
2013-NM-067-AD.

(a) Comments Due Date

    We must receive comments by October 28, 2013.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model DC-9-10, DC-9-30, 
and DC-9-40 series airplanes, certificated in any category, 
identified in Boeing Alert Service Bulletin DC9-A53-144, Revision 2, 
dated February 23, 1984.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 5312, Fuselage Main Bulkhead.

(e) Unsafe Condition

    This AD was prompted by an evaluation by the design approval 
holder (DAH) indicating that the fuselage bulkhead web area is 
subject to widespread fatigue damage (WFD). We are issuing this AD 
to prevent fatigue cracking of the bulkhead, which could result in 
reduced structural integrity of the airplane.

(f) Compliance

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

(g) Modification

    For airplanes on which the modification (AD4 rivets replaced 
with AD5 rivets) required by AD 85-01-02 R1, Amendment 39-5241 (51 
FR 6101, dated February 20, 1988) has not been done: Before the 
accumulation of 72,000 total flight cycles, or within 18 months 
after the effective date of this AD, whichever occurs later, modify 
the aft pressure bulkhead by removing all affected AD4 rivets and 
doing either a fluorescent penetrant or eddy current inspection 
around the rivet holes for cracks, repairing any cracking, and 
installing five-leaf doublers with AD5 rivets, in accordance with 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
DC9-A53-144, Revision 2, dated February 23, 1984; except as required 
by paragraph (h) of this AD.

    Note 1 to paragraph (g) of this AD: Information on additional 
procedures for the modification can be found in Notes 4, 5, and 6, 
as applicable, of paragraph 1.D., `Compliance' of Boeing Alert 
Service Bulletin DC9-A53-144, Revision 2, dated February 23, 1984.

(h) Exception to Service Information

    If any crack is found during any inspection required by this AD, 
and Boeing Alert Service Bulletin DC9-A53-144, Revision 2, dated 
February 23, 1984, specifies to contact Boeing for appropriate 
action: Before further flight, repair using a method approved in 
accordance with the procedures specified in paragraph (j) of this 
AD.

(i) No Reporting Required

    Sheet 1 of Service Sketch 3109, and Sheet 7 of Service Sketch 
3110B of Boeing Alert Service Bulletin DC9-A53-144, Revision 2, 
dated February 23, 1984; specify reporting the details of any cracks 
found; however, this AD does not require reporting.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles 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 Los Angeles ACO, send it 
to the attention of the person identified in the Related Information 
section of this AD.
    (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 
Structures Authorized Representative for the Boeing Commercial 
Airplanes Delegation Option Authorization Organization who has been 
authorized by the Manager, Los Angeles ACO, to make those findings. 
For a repair method to be approved, the repair must meet the 
certification basis of the airplane, and 14 CFR 25.571, Amendment 
45, and the approval must specifically refer to this AD.

(k) Related Information

    (1) For more information about this AD, contact Eric Schrieber, 
Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles 
Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, 
CA 90712-4137; phone: (562) 627-5348; fax: (562) 627-5210; email: 
eric.schrieber@faa.gov.
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
3855 Lakewood Boulevard, MC D800-0019, Long Beach, CA 90846-0001; 
telephone 206-544-5000, extension 2; fax 206-766-5683; 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 August 30, 2013.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-22147 Filed 9-10-13; 8:45 am]
BILLING CODE 4910-13-P
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