
[Federal Register Volume 78, Number 239 (Thursday, December 12, 2013)]
[Proposed Rules]
[Pages 75512-75515]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-29593]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-1027; Directorate Identifier 2013-NM-121-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 737-600, -700, 700C, -800, -900, and -
900ER series airplanes. This proposed AD was prompted by a report of 
installation of incorrect wire support clamps within the left and right 
Environmental Control Systems (ECS) bay area during production, which 
is a flammable leakage zone. Use of incorrect wire support clamps that 
are not fully cushioned could allow electrical power wiring to come in 
contact with the exposed metal of the improper clamp, causing a short 
circuit and subsequent electrical arcing. This proposed AD would 
require inspecting to identify the part number of the wire support 
clamp, and related investigative and corrective actions if necessary. 
We are proposing this AD to prevent electrical arcing and a potential 
ignition source, which, in combination with flammable fuel vapors, 
could result in a fuel tank explosion, and consequent loss of the 
airplane.

DATES: We must receive comments on this proposed AD by January 27, 
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, Washington 98124-

[[Page 75513]]

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.

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: Georgios Roussos, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; 
phone: 425-917-6482; fax: 425-917-6590; email: 
georgios.roussos@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-2013-1027; 
Directorate Identifier 2013-NM-121-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 received a report of the installation of incorrect wire support 
clamps within the left and right Environmental Control Systems (ECS) 
bay area during production, which is a flammable leakage zone. Use of 
incorrect wire support clamps that are not fully cushioned could allow 
electrical power wiring to come in contact with the exposed metal of 
the improper clamp, causing a short circuit and subsequent electrical 
arcing. We are proposing this AD to prevent electrical arcing and a 
potential ignition source, which, in combination with flammable fuel 
vapors, could result in a fuel tank explosion, and consequent loss of 
the airplane.

Related Rulemaking

    On November 18, 2010, we issued AD 2010-24-11, Amendment 39-16530 
(75 FR 74616, December 1, 2010) for certain The Boeing Company Model 
737-600, -700, -800, and -900 series airplanes. That AD required 
sealing the fasteners on the front end rear spars inside the main fuel 
tank and on the lower panel of the center fuel tank, inspecting the 
wire bundle support installation in the equipment cooling system bays 
to identify the type of clamp installed, and determine whether the 
Teflon sleeve was installed, and doing related corrective actions if 
necessary.
    On February 20, 2013, we issued AD 2013-04-11, Amendment 39-17369 
(78 FR 14644, March 7, 2013) for certain The Boeing Company Model 737-
600, -700, -800, and -900ER series airplanes. That AD required 
inspections to identify the part number of the wire support clamp, 
related investigative actions, and corrective actions if necessary.

Relevant Service Information

    We reviewed Boeing Special Attention Service Bulletin 737-28-1312, 
dated April 19, 2013. For information on the procedures and compliance 
times, see this service information at http://www.regulations.gov by 
searching for Docket No. FAA-2013-1027. The related investigative 
actions include an eddy current inspection of the wing front spar for 
cracking and a detailed inspection of the bolt forward of the wing 
front spar upper chord for cracking or missing bolts. The corrective 
actions include repairing cracking and replacing bolts with new bolts.

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. The phrase ``related 
investigative actions'' is used in this proposed AD. ``Related 
investigative actions'' are those actions that are identified as 
follow-on actions that are: (1) Related to the primary action, and (2) 
are on-condition actions that further investigate the nature of any 
condition found. Related investigative actions could include, for 
example, inspections.
    In addition, the phrase ``corrective actions'' is used in this 
proposed AD. ``Corrective actions'' are those actions that are on-
condition actions that correct or address any condition found. 
Corrective actions could include, for example, repairs, removal and 
replacement, and modifications.

Clarification of Applicability in Paragraph (c) of This Proposed AD

    The NOTE specified in Paragraph 1.A., ``Effectivity,'' of Boeing 
Special Attention Service Bulletin 737-28-1312, dated April 19, 2013, 
is in error. It does not impact the Variable Number list in paragraph 
1.A.1. of that section. Therefore, for the applicability of this 
proposed AD, we have referred to the Variable Number list in paragraph 
1.A.1., ``Effectivity,'' in paragraph (c) of this proposed AD.

Costs of Compliance

    We estimate that this proposed AD affects 519 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..............................  6 work-hours x $85 per hour =            $0        $510      $264,690
                                           $510.
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[[Page 75514]]

    We estimate the following costs to do any necessary related 
investigative and corrective actions that would be required based on 
the results of the proposed inspection. We have no way of determining 
the number of aircraft that might need these actions.

                                               On-Condition Costs
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                                                                                 Parts     Cost per
                  Action                                Labor cost                cost      product
----------------------------------------------------------------------------------------------------
Related investigative and corrective        1 work-hour x $85 per hour = $85.         $3        $88
 actions.
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some of the costs of this proposed 
AD may be covered under warranty, thereby reducing the cost impact on 
affected individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate.
    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition repair of chafed or damaged wiring 
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-2013-1027; Directorate Identifier 
2013-NM-121-AD.

(a) Comments Due Date

    We must receive comments by January 27, 2014.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 737-600, -700, 700C, 
-800, -900, and -900ER series airplanes; certificated in any 
category; having a Variable Number identified in paragraph 1.A.1., 
Effectivity, of Boeing Special Attention Service Bulletin 737-28-
1312, dated April 19, 2013.

(d) Subject

    Air Transport Association (ATA) of America Code 28, Fuel System.

(e) Unsafe Condition

    This AD was prompted by a report of installation of incorrect 
wire support clamps within the left and right Environmental Control 
Systems (ECS) bay area during production, which is a flammable 
leakage zone. Use of incorrect wire support clamps that are not 
fully cushioned could allow electrical power wiring to come in 
contact with the exposed metal of the improper clamp, causing a 
short circuit and subsequent electrical arcing. We are issuing this 
AD to prevent electrical arcing and a potential ignition source, 
which, in combination with flammable fuel vapors, could result in a 
fuel tank explosion, and consequent loss of the airplane.

(f) Compliance

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

(g) Inspection and Related Investigative and Corrective Actions

    Within 60 months after the effective date of this AD: Do a 
detailed inspection to determine if a wire support clamp having part 
number (P/N) TA0930034-10, TA0930034-10P, TA0930034-11, or 
TA0930034-12P is installed, and do all applicable related 
investigative and corrective actions before further flight, in 
accordance with the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 737-28-1312, dated April 19, 2013.

(h) Parts Installation Prohibition

    As of the effective date of this AD, no person may install a 
wire support clamp on any airplane within the ECS area defined in 
the Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 737-28-1312, dated April 19, 2013, unless the clamp has P/N 
TA0930034-10, TA0930034-10P, TA0930034-11, or TA0930034-12P.

(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: 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

[[Page 75515]]

of the local flight standards district office/certificate holding 
district office.

(j) Related Information

    (1) For more information about this AD, contact Georgios 
Roussos, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, 
FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., 
Renton, WA 98057-3356; phone: 425-917-6482; fax: 425-917-6590; 
email: georgios.roussos@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, Washington 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 December 4, 2013.
John P. Piccola,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-29593 Filed 12-11-13; 8:45 am]
BILLING CODE 4910-13-P


