[Federal Register Volume 77, Number 183 (Thursday, September 20, 2012)]
[Proposed Rules]
[Pages 58334-58336]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-23148]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0985; Directorate Identifier 2011-NM-250-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 
chafing damage to a wire bundle that was arcing to hydraulic tubing and 
caused by insufficient separation between the wire bundle and the 
hydraulic tubing in the main landing gear (MLG) wheel well. This 
proposed AD would require an inspection for damage of wire bundles and 
hydraulic tubing on the right side of the forward bulkhead of the MLG 
wheel well; installation of new clamps; and corrective actions, as 
applicable. We are proposing this AD to detect and correct possible 
damage caused by insufficient separation between the wire bundles and 
hydraulic tubing to prevent electrical arcing in a flammable fluid 
leakage zone, which could lead to a wheel well fire.

DATES: We must receive comments on this proposed AD by November 5, 
2012.

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 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; email [email protected]; 
Internet https://www.myboeingfleet.com. You may review copies of the 
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: Marie Hogestad, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; 
phone: (425) 917-6418; 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-2012-0985; 
Directorate Identifier 2011-NM-250-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 a Model 737-800 airplane that was found 
with the circuit breaker of the 2 engine spar valve open. 
Maintenance found that a wire had chafed and was arcing to a hydraulic 
line. The chafing condition was caused by inadequate separation between 
the wire bundle and the hydraulic line. Boeing inspected additional 
airplanes in production and found that there was not sufficient 
separation, based on design requirements, between the wire bundles and 
adjacent hydraulic tubing at that location. Wire chafing damage and 
electrical arcing in a flammable fluid leakage zone could lead to a 
wheel well fire.

Relevant Service Information

    We reviewed Boeing Special Attention Service Bulletin 737-29-1113, 
dated March 23, 2011. That service bulletin describes procedures for a 
general visual inspection for damage of wire bundles W6128, W7122, 
W8122, and W8222 and hydraulic tubing part numbers (P/Ns) 272A4451-136 
and 272A4451-137, installation of new clamps between the wire bundles 
and the adjacent hydraulic tubing, and corrective actions as 
applicable. Corrective actions include repairing damaged wire bundles 
and replacing or repairing damaged hydraulic tubing.

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

[[Page 58335]]

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 the Proposed AD and the Service 
Information.''

Differences Between the Proposed AD and the Service Information

    The applicability of the proposed AD differs from paragraph 1.A., 
``Effectivity,'' in Boeing Special Attention Service Bulletin 737-29-
1113, dated March 23, 2011, to be consistent with the effectivity 
specified in a correction provided in Boeing Information Notice (IN) 
737-29-1113 IN 01, dated May 20, 2011.
    Where Boeing Special Attention Service Bulletin 737-29-1113, dated 
March 23, 2011 specifies a compliance time ``after the original issue 
date of this service bulletin,'' this proposed AD would require 
compliance within the specified compliance time after the effective 
date of this AD.

Costs of Compliance

    We estimate that this proposed AD affects 520 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 installation........  2 work-hours x $85 per hour              $0            $170         $88,400
                                      = $170.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
labor cost estimates for the on-condition actions (repairing or 
replacing of damaged wire bundles and damaged hydraulic tubing) 
specified in this proposed AD.
    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.

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

    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]

    2. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive (AD):

The Boeing Company: Docket No. FAA-2012-0985; Directorate Identifier 
2011-NM-250-AD.

(a) Comments Due Date

    We must receive comments by November 5, 2012.

(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; line numbers (L/Ns) 1060 through 3347 excluding L/Ns 3138, 
3158, 3169, 3175, 3216, 3224, 3253, 3274, 3290 to 3293 inclusive, 
and 3295 to 3347 inclusive.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 29: Hydraulic Power.

(e) Unsafe Condition

    This AD was prompted by a report of chafing damage to a wire 
bundle that was arcing to hydraulic tubing and caused by 
insufficient separation between the wire bundle and the hydraulic 
tubing in the main landing gear (MLG) wheel well. We are issuing 
this AD to detect and correct possible damage caused by insufficient 
separation between the wire bundles and hydraulic tubing to prevent 
electrical arcing in a flammable fluid leakage zone, which could 
lead to a wheel well fire.

(f) Compliance

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

(g) Inspection and Installation

    Within 24 months after the effective date of this AD: Do a 
general visual inspection of hydraulic tubing having part numbers 
(P/Ns) 272A4451-136 and 272A4451-137, and wire bundles W6128, W7122, 
W8122, and W8222 for wire chafing or damage, install new clamps in 
the right MLG wheel well, and do all applicable corrective actions, 
in accordance with the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 737-29-1113, dated March

[[Page 58336]]

23, 2011. All corrective actions must be done before further flight.

(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 the Related Information 
section 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.

(i) Related Information

    (1) For more information about this AD, contact Marie Hogestad, 
Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, 
Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, 
WA 98057-3356; phone: (425) 917-6418; 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, Washington 98124-2207; telephone 
206-544-5000, extension 1; fax 206-766-5680; email 
[email protected]; Internet https://www.myboeingfleet.com. You 
may review copies of the 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 September 7, 2012.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-23148 Filed 9-19-12; 8:45 am]
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