
[Federal Register Volume 76, Number 114 (Tuesday, June 14, 2011)]
[Proposed Rules]
[Pages 34625-34627]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-14697]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0566; Directorate Identifier 2010-NM-271-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 
747-400D, 747-400F, 747SR, and 747SP Series 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 the 
products listed above. This proposed AD would require modification of 
the fluid drain path in the leading edge area of the wing. This 
proposed AD was prompted by a design review following a ground fire 
incident and reports of flammable fluid leaks from the wing leading 
edge area onto the engine exhaust area. We are proposing this AD to 
prevent flammable fluid from leaking onto the engine exhaust nozzle, 
which could result in a fire.

DATES: We must receive comments on this proposed AD by July 29, 2011.

ADDRESSES: You may send comments 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; phone: 206-
544-5000, extension 1; fax: 206-766-5680; e-mail: me.boecom@boeing.com; 
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: Tung Tran, Aerospace Engineer, 
Propulsion Branch, ANM-140S, Seattle Aircraft Certification Office 
(ACO), FAA, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; 
phone: 425-917-6505; fax: 425-917-6590; e-mail: Tung.Tran@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-2011-0566; 
Directorate Identifier 2010-NM-271-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 a report of fuel leaking from the wing leading 
edge area at the inboard end of the number 5 leading edge slat of a 
Model 737 airplane. The leak was discovered during a post-flight 
inspection with a fuel quantity of over 2,500 pounds. Subsequent 
investigation found that the leak occurred in an area of the front spar

[[Page 34626]]

that does not have a proper drain path. This led to the fuel draining 
onto the engine exhaust nozzle. The leak appears to have been caused by 
a loose retaining nut of the slat track down stop. We are proposing 
this AD to prevent flammable fluid from leaking onto the engine exhaust 
nozzle, which could result in a fire.
    A Model 747 design review revealed that some of the design features 
in the Model 737 wing leading edge area also exist in Model 747 
airplanes. Additional design reviews have led to similar findings in 
Model 757 and Model 767 airplanes. We have issued AD 2010-23-13 
Amendment 39-16502 (75 FR 68688, November 9, 2009), for Model 757 
airplanes, and are considering rulemaking for Model 737 and Model 767 
airplanes.

Relevant Service Information

    We reviewed Boeing Special Attention Service Bulletin 747-57-2332, 
dated November 9, 2010. This service information divides the affected 
airplanes into 10 groups. For all groups, this service information 
describes procedures for modifying the fluid drain path in the leading 
edge area of the wing. The modification consists of changing fluid dam 
assemblies at the wing outboard leading edge station (OLES) 1250, and 
installing seal assemblies at OLES 1185. Additionally, this service 
information specifies changing the lower leading edge wing panels 
through repairs, parts installation, and installing drain tube 
assemblies.
    For Groups 1 through 6, this service information also specifies 
installing fluid dam assemblies at wing inboard leading edge station 
770.

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.

Costs of Compliance

    We estimate that this proposed AD will affect 258 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
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Fluid drainage modification       95 work-hours x $85 per            $33,609           $41,684        $5,960,812
 (Groups 1-6) (143 airplanes).     hour = $8,075.
Fluid drainage modification       90 work-hours x $85 per             29,304            36,954         4,249,710
 (Groups 7-10) (115 airplanes).    hour = $7,650.
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    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-2011-0566; Directorate Identifier 
2010-NM-271-AD.

Comments Due Date

    (a) We must receive comments by July 29, 2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 
747-400D, 747-400F, 747SR, and 747SP series airplanes, certificated 
in any category, as identified in Boeing Special Attention Service 
Bulletin 747-57-2332, dated November 9, 2010.

[[Page 34627]]

Subject

    (d) Joint Aircraft System Component (JASC)/Air Transport 
Association (ATA) of America Code 57: Wings.

Unsafe Condition

    (e) This AD was prompted by a design review following a ground 
fire incident and reports of flammable fluid leaks from the wing 
leading edge area onto the engine exhaust area. We are issuing this 
AD to prevent flammable fluid from leaking onto the engine exhaust 
nozzle, which could result in a fire.

Compliance

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

Leading Edge Installation

    (g) Within 60 months after the effective date of this AD, modify 
the fluid drain path in the leading edge area of the wing, in 
accordance with the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 747-57-2332, dated November 9, 2010.

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Seattle Aircraft Certification Office, 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 e-mailed 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.

Related Information

    (i) For more information about this AD, contact Tung Tran, 
Aerospace Engineer, Propulsion Branch, ANM-140S, Seattle Aircraft 
Certification Office (ACO), FAA, 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; phone: 425-917-6505; fax: 425-917-6590; e-
mail: Tung.Tran@faa.gov.
    (j) 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; phone: 206-
544-5000, extension 1; fax: 206-766-5680; e-mail: 
me.boecom@boeing.com; 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 June 7, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-14697 Filed 6-13-11; 8:45 am]
BILLING CODE 4910-13-P


