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[Federal Register Volume 79, Number 131 (Wednesday, July 9, 2014)]
[Proposed Rules]
[Pages 38799-38801]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-16008]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2014-0429; Directorate Identifier 2014-NM-039-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 747-400 and 747-400F series airplanes. 
This proposed AD was prompted by reports of cracking in the main 
equipment center (MEC) drip shield and exhaust plenum. This proposed AD 
would require installing a fiberglass reinforcing overcoat on the MEC 
drip shield. We are proposing this AD to prevent water penetration into 
the MEC, which could result in an electrical short and potential loss 
of several functions essential for safe flight.

DATES: We must receive comments on this proposed AD by August 25, 2014.

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.

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-2014-
0429; 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: Francis Smith, Aerospace Engineer, 
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle 
Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-
3356; telephone: 425-917-6596; fax: 425-917-6590; email: 
Francis.Smith@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-

[[Page 38800]]

2014-0429; Directorate Identifier 2014-NM-039-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

    We have received reports of cracking in the MEC drip shield and 
exhaust plenum, which have each been identified as part of the leak 
path into the MEC. Multiple operators have reported a cracked MEC drip 
shield. These cracks can allow water to penetrate the MEC drip shield 
and enter the MEC. Water penetration into the MEC, if not detected and 
corrected, could result in an electrical short and potential loss of 
several functions essential for safe flight.

Related Rulemaking

    We have previously issued AD 2011-16-06, Amendment 39-16764 (76 FR 
47427, August 5, 2011), for certain The Boeing Company Model 747-400 
and 747-400F series airplanes. AD 2011-16-06 requires inspecting for 
cracks and holes of the MEC drip shields, repairing cracks, stiffening 
the drip shield top surface, and installing a fiberglass reinforcing 
overcoat to the top and sides of the drip shield. We have since 
received reports of additional cracking of the drip shield that is not 
mitigated by AD 2011-16-06. The newly reported cracking occurs at the 
lower radius of the MEC drip shield, adjacent to the floor beams.

Relevant Service Information

    We reviewed Boeing Alert Service Bulletin 747-25A3640, dated 
January 8, 2014. For information on the procedures and compliance 
times, see this service information at http://www.regulations.gov by 
searching for Docket No. FAA-2014-0429.

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.

Explanation of ``RC'' Steps in Service Information

    The FAA worked in conjunction with industry, under the 
Airworthiness Directive Implementation Aviation Rulemaking Committee, 
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 actions specified in the service 
information described previously include steps that are labeled as RC 
(required for compliance) because these steps have a direct effect on 
detecting, preventing, resolving, or eliminating an identified unsafe 
condition.
    As noted in the specified service information, steps labeled as RC 
must be done to comply with the proposed AD. However, steps that are 
not labeled as RC are recommended. Those steps that are not labeled as 
RC may be deviated from, done as part of other actions, or done using 
accepted methods different from those identified in the service 
information without obtaining approval of an alternative method of 
compliance, provided the steps labeled as RC can be done and the 
airplane can be put back in a serviceable condition. Any substitutions 
or changes to steps labeled as RC will require approval of an 
alternative method of compliance.

Costs of Compliance

    We estimate that this proposed AD affects 15 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
----------------------------------------------------------------------------------------------------------------
Installation of a fiberglass          36 work-hours x $85 per              $0           $3,060          $45,900
 reinforcing overcoat on the MEC       hour = $3,060.
 drip shield.
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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.

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.

[[Page 38801]]

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-2014-0429; Directorate Identifier 
2014-NM-039-AD.

(a) Comments Due Date

    We must receive comments by August 25, 2014.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 747-400 and 747-400F 
airplanes, certificated in any category, as identified in Boeing 
Alert Service Bulletin 747-25A3640, dated January 8, 2014.

(d) Subject

    Air Transport Association (ATA) of America Code 25, Equipment/
Furnishings.

(e) Unsafe Condition

    This AD was prompted by reports of cracking in the main 
equipment center (MEC) drip shield and exhaust plenum. We are 
issuing this AD to prevent water penetration into the MEC, which 
could result in an electrical short and potential loss of several 
functions essential for safe flight.

(f) Compliance

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

(g) Installation

    Within 24 months after the effective date of this AD, install a 
fiberglass reinforcing overcoat on the MEC drip shield, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 747-25A3640, dated January 8, 2014.

(h) 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 (i)(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) If the service information contains steps that are labeled 
as RC (Required for Compliance), those steps must be done to comply 
with this AD; any steps that are not labeled as RC are recommended. 
Those steps that are not labeled as RC may be deviated from, done as 
part of other actions, or done using accepted methods different from 
those identified in the specified service information without 
obtaining approval of an AMOC, provided the steps labeled as RC can 
be done and the airplane can be put back in a serviceable condition. 
Any substitutions or changes to steps labeled as RC require approval 
of an AMOC.

 (i) Related Information

    (1) For more information about this AD, Francis Smith, Aerospace 
Engineer, Cabin Safety and Environmental Systems Branch, ANM-150S, 
FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., 
Renton, WA 98057-3356; telephone: 425-917-6596; fax: 425-917-6590; 
email: Francis.Smith@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, WA. For information on the availability of this 
material at the FAA, call 425-227-1221.

    Issued in Renton, Washington, on June 26, 2014.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2014-16008 Filed 7-8-14; 8:45 am]
BILLING CODE 4910-13-P
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