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[Federal Register Volume 80, Number 131 (Thursday, July 9, 2015)]
[Proposed Rules]
[Pages 39394-39397]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-16763]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-2460; Directorate Identifier 2014-NM-163-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) 2010-26-
10, which applies to certain The Boeing Company Model 747-200C, -200F, 
-400, -400D, and -400F series airplanes. AD 2010-26-10 currently 
requires repetitive inspections for cracking of the lap joints, 
modification of certain lap joints, and certain post-repair inspections 
of the lap joints. Since we issued AD 2010-26-10, an evaluation by the 
design approval holder (DAH) has indicated that certain lap joints are 
subject to widespread fatigue damage (WFD). This proposed AD would add 
new repetitive post-modification inspections for cracking in the lap 
joints, and repair if necessary. We are proposing this AD to detect and 
correct fatigue cracking in certain lap joints, which could result in 
rapid depressurization and consequent reduced structural integrity of 
the airplane.

DATES: We must receive comments on this proposed AD by August 24, 2015.

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 view this 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. It 
is also available on the Internet at http://www.regulations.gov by 
searching for and locating Docket No. FAA-2015-2460.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
2460; 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

[[Page 39395]]

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

FOR FURTHER INFORMATION CONTACT: Nathan Weigand, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6428; fax: 
425-917-6590; email: nathan.p.weigand@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-2015-2460; 
Directorate Identifier 2014-NM-163-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 13, 2010, we issued AD 2010-26-10, Amendment 39-16549 
(75 FR 81427, December 28, 2010), for certain Model 747-200C, -200F, -
400, -400D, and -400F series airplanes. AD 2010-26-10 requires 
repetitive inspections for cracking of the lap joints, modification of 
certain lap joints and certain post-repair inspections of the lap 
joints. AD 2010-26-10 resulted from a structural review of affected 
skin lap joints for WFD. We issued AD 2010-26-10 to prevent fatigue 
cracking in certain lap joints, which could result in rapid 
depressurization and consequent reduced structural integrity of the 
airplane.

Widespread Fatigue Damage

    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 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 2010-26-10, Amendment 39-16549 (75 FR 81427, December 
28, 2010), Was Issued

    Since we issued AD 2010-26-10, Amendment 39-16549 (75 FR 81427, 
December 28, 2010), an evaluation by the DAH has indicated that certain 
lap joints are subject to WFD.

Related Service Information Under 1 CFR part 51

    We reviewed Boeing Alert Service Bulletin 747-53A2499, Revision 3, 
dated July 15, 2014. The service information describes procedures for 
body skin lap joint inspections and modifications in sections 41, 42, 
and 43. This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in the ADDRESSES section of this 
NPRM.

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 2010-26-10, Amendment 39-16549 (75 FR 81427, 
December 28, 2010), this proposed AD would retain all of the 
requirements of AD 2010-26-10. Those requirements are referenced in the 
service information identified previously, which, in turn, is 
referenced in paragraphs (g) and (h) of this proposed AD. This proposed 
AD would require accomplishing the actions specified in the service 
information described previously, except as discussed under 
``Difference Between this Proposed AD and the Service Bulletin.'' Refer 
to this service information for details on the procedures and 
compliance times.

Difference Between This Proposed AD and the Service Bulletin

    Although Boeing Alert Service Bulletin 747-53A2499, Revision 3, 
dated July 15, 2014, specifies that operators may contact the 
manufacturer for disposition of certain repair conditions, 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

[[Page 39396]]

Designation Authorization (ODA) whom we have authorized to make those 
findings.

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

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Pre-modification inspections       Up to 675 work-                  $0  Up to $57,375 per    Up to $6,885,000
 [retained action from AD 2010-26-  hours, = up to                       inspection cycle.    per inspection
 10, Amendment 39-16549 (75 FR      $57,375.                                                  cycle.
 81427, December 28, 2010)].
Modification [retained action      Up to 5,819 work-                 0  Up to $494,615.....  Up to $59,353,800.
 from AD 2010-26-10, Amendment 39-  hours x $85 per
 16549 (75 FR 81427, December 28,   hour = up to
 2010)].                            $494,615.
New proposed post-modification     Up to 105 work-                   0  Up to $8,925 per     Up to $1,071,000
 inspections.                       hours x $85 per                      inspection cycle.    per inspection
                                    hour = up to                                              cycle.
                                    $8,925.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
a cost estimate 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) 
2010-26-10, Amendment 39-16549 (75 FR 81427, December 28, 2010), and 
adding the following new AD:

The Boeing Company: Docket No. FAA-2015-2460; Directorate Identifier 
2014-NM-163-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by August 24, 
2015.

(b) Affected ADs

    This AD replaces AD 2010-26-10, Amendment 39-16549 (75 FR 81427, 
December 28, 2010).

(c) Applicability

    This AD applies to The Boeing Company Model 747-200C, -200F, -
400, -400D, and -400F series airplanes; certificated in any 
category; as identified in Boeing Alert Service Bulletin 747-
53A2499, Revision 3, dated July 15, 2014.

(d) Subject

    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 lap joints are subject to 
widespread fatigue damage (WFD). We are issuing this AD to detect 
and correct fatigue cracking in certain lap joints, which could 
result in rapid depressurization and consequent reduced structural 
integrity of the airplane.

(f) Compliance

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

(g) Repetitive Lap Joint Inspections

    At the applicable time specified in Table 1 and Table 3 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
747-53A2499, Revision 3, dated July 15, 2014, except as required by 
paragraph (j)(1) of this AD: Do eddy current inspections for cracks 
in the skin of the lap joints, and do all applicable repairs, in 
accordance with the Accomplishment Instructions of Boeing

[[Page 39397]]

Alert Service Bulletin 747-53A2499, Revision 3, dated July 15, 2014, 
except as required by paragraph (j)(2) of this AD. Do all applicable 
repairs before further flight. Repeat the applicable inspections 
thereafter at intervals not to exceed those specified in Table 1 and 
Table 3 of paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 747-53A2499, Revision 3, dated July 15, 2014

(h) Lap Joint Modification

    At the applicable time specified in Tables 2, 4, 5, and 6 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
747-53A2499, Revision 3, dated July 15, 2014, except as required by 
paragraph (j)(1) of this AD: Modify the applicable lap joints, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 747-53A2499, Revision 3, dated July 15, 2014, 
except as required by paragraph (j)(2) of this AD. Accomplishment of 
the modification required by this paragraph terminates the 
repetitive inspections required by paragraph (g) of this AD for the 
length of the modified lap joint.

(i) Lap Joint Post-Modification Inspections

    At the applicable time specified in Tables 7, 8, 9, and 10 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
747-53A2499, Revision 3, dated July 15, 2014, except as required by 
paragraph (j)(1) of this AD: Do the applicable inspections specified 
in paragraph (i)(1), (i)(2), or (i)(3) of this AD, in accordance 
with the Accomplishment Instructions of Boeing Alert Service 
Bulletin 747-53A2499, Revision 3, dated July 15, 2014. Repeat the 
applicable inspections thereafter at the applicable times specified 
in Tables 7, 8, 9, and 10 of paragraph 1.E, ``Compliance,'' of 
Boeing Alert Service Bulletin 747-53A2499, Revision 3, dated July 
15, 2014. If any crack is found during any inspection, repair before 
further flight using a method approved in accordance with the 
procedures specified in paragraph (l) of this AD.
    (1) For airplanes identified as Groups 2 through 5 and 8 through 
10 in Boeing Alert Service Bulletin 747-53A2499, Revision 3, dated 
July 15, 2014: Internal detailed and surface high frequency eddy 
current (HFEC) inspections for any crack in the skin or internal 
doubler.
    (2) For airplanes identified as Groups 6, 11, and 19 in Boeing 
Alert Service Bulletin 747-53A2499, Revision 3, dated July 15, 2014: 
External detailed and low frequency eddy current inspections of the 
upper and lower skin panels for cracking, external detailed and HFEC 
inspections of the doubler for cracking, and internal detailed and 
HFEC inspections of the upper and lower skin panels for cracking 
(for airplanes with a stringer 6 lap joint modification installed 
between STA 340 and STA 400 as specified in Boeing Service Bulletin 
747-53-2272); or internal detailed and surface HFEC inspections for 
any crack in the skin or internal doubler (for airplanes with lap 
joints modified as specified in Boeing Alert Service Bulletin 747-
53A2499.)
    (3) For airplanes identified as Groups 1, 7, and 12 through 18 
in Boeing Alert Service Bulletin 747-53A2499, Revision 3, dated July 
15, 2014: Internal detailed and surface HFEC inspections for any 
crack in the skin or internal doubler.

(j) Exceptions to Service Bulletin Procedures

    (1) Where Boeing Alert Service Bulletin 747-53A2499, Revision 3, 
dated July 15, 2014, specifies a compliance time ``after the 
Revision 3 date of this service bulletin,'' this AD requires 
compliance within the specified compliance time after the effective 
date of this AD.
    (2) Where Boeing Alert Service Bulletin 747-53A2499, Revision 3, 
dated July 15, 2014, specifies to contact Boeing for repair 
instructions: Before further flight, repair using a method approved 
in accordance with the procedures specified in paragraph (l) of this 
AD.

(k) Credit for Previous Actions

    Actions done before the effective date of this AD using the 
service information identified in paragraph (k)(1) or (k)(2) of this 
AD are acceptable for compliance with the corresponding requirements 
of paragraphs (g) and (h) of this AD.
    (1) Boeing Alert Service Bulletin 747-53A2499, Revision 1, dated 
October 30, 2008, which is not incorporated by reference in this AD.
    (2) Boeing Alert Service Bulletin 747-53A2499, Revision 2, dated 
August 12, 2010, which was incorporated by reference in AD 2010-26-
10, Amendment 39-16549 (75 FR 81427, December 28, 2010).

(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)(1) 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.
    (4) AMOCs approved for AD 2010-26-10, Amendment 39-16549 (75 FR 
81427, December 28, 2010), are approved as AMOCs for the 
corresponding provisions of paragraphs (g) and (h) this AD.

(m) Related Information

    (1) For more information about this AD, contact Nathan Weigand, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; 
phone: 425-917-6428; fax: 425-917-6590; email: 
nathan.p.weigand@faa.gov.
    (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 view this 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 June 29, 2015.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-16763 Filed 7-8-15; 8:45 am]
BILLING CODE 4910-13-P
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