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[Federal Register Volume 80, Number 56 (Tuesday, March 24, 2015)]
[Proposed Rules]
[Pages 15525-15528]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2015-06576]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-0493; Directorate Identifier 2014-NM-184-AD]
RIN 2120-AA64

Airworthiness Directives; Lockheed Martin Corporation/Lockheed 
Martin Aeronautics 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 Lockheed Martin Corporation/Lockheed Martin Aeronautics Company 
Model 188 series airplanes. This proposed AD was prompted by an 
evaluation by the design approval holder (DAH) indicating that the 
upper and lower wing skin planks at the attachment of the main landing 
gear (MLG) ribs at certain wing-stations are subject to widespread 
fatigue damage (WFD). This proposed AD would require an inspection (for 
cracking) and modification of the chordwise fastener rows of the upper 
and lower wing planks at the attachments to the MLG ribs at certain 
wing-stations. We are proposing this AD to prevent fatigue cracking of 
the upper and lower wing skin planks at the attachment of the MLG ribs, 
which could result in failure of the wing.

DATES: We must receive comments on this proposed AD by May 8, 2015.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:

[[Page 15526]]

     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 
Lockheed Martin Corporation/Lockheed Martin Aeronautics Company, 
Airworthiness Office, Dept. 6A0M, Zone 0252, Column P-58, 86 S. Cobb 
Drive, Marietta, GA 30063; telephone 770-494-5444; fax 770-494-5445; 
email ams.portal@lmco.com; Internet http://www.lockheedmartin.com/ams/tools/TechPubs.html. 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.

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-
0493; 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: Carl Gray, Aerospace Engineer, 
Airframe Branch, ACE-117A, FAA, Atlanta Aircraft Certification Office 
(ACO), 1701 Columbia Avenue, College Park, GA 30337; phone: 404-474-
5554; fax: 404-474-5605; email: Carl.W.Gray@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-2015-0493; 
Directorate Identifier 2014-NM-184-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.
    This proposed AD was prompted by an evaluation by the DAH 
indicating that the upper and lower wing skin planks at the attachment 
of the MLG ribs are subject to WFD. The root cause of WFD is fatigue 
cracks manifesting and growing simultaneously at similar structural 
details and stress levels of the upper and lower wing skin planks at 
the attachment of the MLG ribs. Fatigue cracking is increasingly likely 
as the airplane is operated and aged, and without intervention, fatigue 
cracking of the upper and lower wing skin planks at the attachment of 
the MLG ribs could result in failure of the wing.

Related Service Information Under 1 CFR Part 51

    We reviewed Lockheed Martin Electra 88 Service Bulletin 721, dated 
April 30, 2014. This service bulletin describes procedures to do a bolt 
hole eddy current (BHEC) inspection for cracking and modification of 
the chordwise fastener rows of the upper and lower wing planks at the 
attachments to the MLG ribs at wing-station (WS) 167 and WS 209 by 
removing the original fasteners and replacing them with new first 
oversize fasteners of the same type or approved substitute type for 
original fasteners. Corrective actions include repairing any cracking 
before further flight. The compliance times for the inspection and 
modification are specified at the following times.
     For WS 167 lower: Before the accumulation of 33,300 total 
flight hours.
     For WS 167 upper: Before the accumulation of 23,200 total 
flight hours.
     For WS 209 lower: Before the accumulation of 31,500 total 
flight hours.

[[Page 15527]]

     For WS 209 upper: Before the accumulation of 35,400 total 
flight hours.
    This service information is reasonably available; see ADDRESSES for 
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 these same type 
designs.

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.''

Differences Between This Proposed AD and the Service Information

    Operators should note that, although the Accomplishment 
Instructions of Lockheed Martin Electra 88 Service Bulletin 721, dated 
April 30, 2014, describe procedures for reporting any damage detected 
to the manufacturer, this proposed AD would not require those actions.
    Although Lockheed Martin Electra Service Bulletin 88/721, dated 
April 30, 2014, specifies that operators may contact the manufacturer 
for disposition of certain repair conditions, this proposed AD would 
require operators to repair those conditions in accordance with a 
method approved by the FAA.

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

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                    Cost per       Cost on U.S.
               Action                        Labor cost           Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
Inspection and Modification.........  560 work-hours x $85             $5,000          $52,600         $210,400
                                       per hour = $47,600.
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    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):

Lockheed Martin Corporation/Lockheed Martin Aeronautics Company: 
Docket No. FAA-2015-0493; Directorate Identifier 2014-NM-184-AD.

(a) Comments Due Date

    We must receive comments by May 8, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Lockheed Martin Corporation/Lockheed Martin 
Aeronautics Company Model 188A and 188C airplanes, certificated in 
any category, serial numbers 1001 and subsequent.

 (d) Subject

    Air Transport Association (ATA) of America Code 57, Wings.

(e) Unsafe Condition

    This AD was prompted by an evaluation by the design approval 
holder (DAH) indicating that the upper and lower wing skin planks at 
the attachment of the main landing gear (MLG) ribs at certain wing-
stations are subject to widespread fatigue damage (WFD). We are 
issuing this AD to prevent fatigue cracking of the upper and lower 
wing skin planks at the attachment of the MLG ribs, which could 
result in failure of the wing.

(f) Compliance

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

[[Page 15528]]

(g) Inspection, Modification, and Corrective Action

    At the later of the times specified in paragraphs (g)(1) and 
(g)(2) of this AD: Remove the chordwise fastener rows of the upper 
and lower wing planks at the attachments to the MLG ribs at wing-
station (WS) 167 and WS 209; do a bolt hole eddy current (BHEC) 
inspection to detect cracking of the fastener rows; and replace the 
original fasteners with new, first oversize fasteners; in accordance 
with the Accomplishment Instructions of Lockheed Martin Electra 88 
Service Bulletin 721, dated April 30, 2014. If any cracking is found 
during any inspection required by this paragraph: Before further 
flight, repair the cracking, in accordance with the Accomplishment 
Instructions of Lockheed Martin Electra 88 Service Bulletin 721, 
dated April 30, 2014.
    (1) At the applicable time specified in table 1 of paragraph 
1.E., ``Compliance,'' of Lockheed Martin Electra 88 Service Bulletin 
721, dated April 30, 2014. Where table 1 of paragraph 1.E., 
``Compliance,'' of Lockheed Martin Electra 88 Service Bulletin 721, 
dated April 30, 2014, specifies ``Flt. Hrs,'' this AD specifies 
``total flight hours.''
    (2) Within 365 days or 600 flight hours after the effective date 
of this AD, whichever occurs first.

(h) No Reporting

    Although Lockheed Martin Electra 88 Service Bulletin 721, dated 
April 30, 2014, specifies to submit certain information to the 
manufacturer, this AD does not include that requirement.

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Atlanta 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.
    (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.

(j) Related Information

    (1) For more information about this AD, Carl Gray, Aerospace 
Engineer, Airframe Branch, ACE-117A, FAA, Atlanta ACO, 1701 Columbia 
Avenue, College Park, GA 30337; phone: 404-474-5554; fax: 404-474-
5605; email: carl.w.gray@faa.gov.
    (2) For service information identified in this AD, contact 
Lockheed Martin Corporation/Lockheed Martin Aeronautics Company, 
Airworthiness Office, Dept. 6A0M, Zone 0252, Column P-58, 86 S. Cobb 
Drive, Marietta, GA 30063; telephone 770-494-5444; fax 770-494-5445; 
email ams.portal@lmco.com; Internet http://www.lockheedmartin.com/ams/tools/TechPubs.html. You may view this 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 March 12, 2015.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-06576 Filed 3-23-15; 8:45 am]
 BILLING CODE 4910-13-P
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