[Federal Register Volume 80, Number 91 (Tuesday, May 12, 2015)]
[Proposed Rules]
[Pages 27116-27119]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-11351]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-1281; Directorate Identifier 2014-NM-241-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 all 
The Boeing Company Model 777 airplanes. This proposed AD was prompted 
by an evaluation by the design approval holder (DAH) indicating that 
the lap splices of the aft pressure bulkhead webs are subject to 
widespread fatigue damage (WFD). This proposed AD would require 
repetitive inspections for any crack in the aft webs of the radial lap 
splices of the aft pressure bulkhead, and, if necessary, corrective 
actions. We are proposing this AD to detect and correct fatigue 
cracking in the aft webs of the radial lap splices of the aft pressure 
bulkhead, which could result in reduced structural integrity of the 
airplane and decompression of the cabin.

DATES: We must receive comments on this proposed AD by June 26, 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

[[Page 27117]]

& 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://regulations.gov by searching for and locating Docket 
No. FAA-2015-1281.

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-
1281; 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: Haytham Alaidy, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6573; 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 proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2015-1281; 
Directorate Identifier 2014-NM-241-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 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.
    Cracks in the aft webs of the radial lap splices of the aft 
pressure bulkhead can rapidly coalesce, and could result in reduced 
structural integrity of the airplane and decompression of the cabin.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 777-53A0078, dated 
December 5, 2014. The service information describes procedures for 
inspecting the aft webs of the radial lap splices of the aft pressure 
bulkhead and repairing any crack. Refer to this service information for 
information on the procedures and compliance times. This service 
information is reasonably available at http://www.regulations.gov by 
searching for and locating Docket No. FAA-2015-1281. Or see ADDRESSES 
for other ways to access this service information.

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 described previously except as discussed 
under ``Differences Between This Proposed AD and the Service 
Information.''
    The phrase ``corrective actions'' might be 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.

Differences Between This Proposed AD and the 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.

[[Page 27118]]

Explanation of ``Required for Compliance'' (RC) Steps in Service 
Information

    The FAA worked in conjunction with industry, under the 
Airworthiness Directive Implementation Aviation Rulemaking Committee 
(ARC), to enhance the AD system. One enhancement was a new process for 
annotating which steps in the service information are required for 
compliance with an AD. Differentiating these steps from other tasks in 
the service information is expected to improve an owner's/operator's 
understanding of crucial AD requirements and help provide consistent 
judgment in AD compliance. The steps identified as RC (required for 
compliance) in any service information identified previously have a 
direct effect on detecting, preventing, resolving, or eliminating an 
identified unsafe condition.
    Steps that are identified as RC in any service information must be 
done to comply with the proposed AD. However, steps that are not 
identified as RC are recommended. Those steps that are not identified 
as RC may be deviated from using accepted methods in accordance with 
the operator's maintenance or inspection program without obtaining 
approval of an alternative method of compliance (AMOC), provided the 
steps identified as RC can be done and the airplane can be put back in 
a serviceable condition. Any substitutions or changes to steps 
identified as RC will require approval of an AMOC.

Costs of Compliance

    We estimate that this proposed AD affects 193 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
----------------------------------------------------------------------------------------------------------------
Inspection.....................  9 work-hours x $85 per               $0   $765 per            $147,645 per
                                  hour = $765 per                           inspection cycle.   inspection
                                  inspection cycle.                                             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 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-2015-1281; Directorate Identifier 
2014-NM-241-AD.

(a) Comments Due Date

    We must receive comments by June 26, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 777-200, -200LR, 
-300, -300ER, and 777F series airplanes, certificated in any 
category.

(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 the lap splices of the aft pressure 
bulkhead webs are subject to widespread fatigue damage (WFD). We are 
issuing this AD to detect and correct fatigue cracking in the aft 
webs of the radial lap splices of the aft pressure bulkhead, which 
could result in reduced structural integrity of the airplane and 
decompression of the cabin.

(f) Compliance

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

(g) Inspection of Lap Splice in the Web of the Aft Pressure Bulkhead

    Except as required by paragraph (h) of this AD: At the times 
specified in paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 777-53A0078, dated December 5, 2014, do a medium frequency 
eddy current inspection for any cracking in the aft webs of the 
radial lap splices of the aft pressure bulkhead, in accordance with 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
777-53A0078, dated December 5, 2014. Repeat the inspection 
thereafter at intervals not to exceed 8,400 flight cycles from the 
previous inspection. If any crack is found during any inspection 
required by this paragraph, do the applicable corrective actions, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 777-53A0078, dated December 5, 2014. If a 
corrective action described in Boeing Alert Service Bulletin

[[Page 27119]]

777-53A0078, dated December 5, 2014, specifies to contact Boeing for 
appropriate action: Before further flight, repair using a method 
approved in accordance with the procedures specified in paragraph 
(i) of this AD.

(h) Exception to Service Information Specifications

    Where Boeing Alert Service Bulletin 777-53A0078, dated December 
5, 2014, specifies a compliance time ``after the original issue date 
of this service bulletin,'' this AD requires compliance within the 
specified compliance time after the effective date of this AD.

(i) 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 (j)(1) 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) If any service information contains steps that are 
identified as RC (Required for Compliance), those steps must be done 
to comply with this AD; any steps that are not identified as RC are 
recommended. Those steps that are not identified as RC may be 
deviated from using accepted methods in accordance with the 
operator's maintenance or inspection program without obtaining 
approval of an AMOC, provided the steps identified as RC can be done 
and the airplane can be put back in a serviceable condition. Any 
substitutions or changes to steps identified as RC require approval 
of an AMOC.

(j) Related Information

    (1) For more information about this AD, contact Haytham Alaidy, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057-
3356; phone: 425-917-6573; 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 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.

    Issued in Renton, Washington, on May 1, 2015.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-11351 Filed 5-11-15; 8:45 am]
 BILLING CODE 4910-13-P