[Federal Register Volume 77, Number 113 (Tuesday, June 12, 2012)]
[Proposed Rules]
[Pages 34879-34881]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-14245]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0591; Directorate Identifier 2012-NM-015-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 supersede an existing airworthiness directive 
(AD) that applies to certain The Boeing Company Model 737-600, -700, -
700C, -800, and -900 series airplanes. The existing AD currently 
requires replacing the drain tube assemblies and support clamps on the 
aft fairing of the engine struts. Since we issued that AD, we received 
an additional report of a broken drain tube assembly on the aft fairing 
of the left engine strut at the clamp support location under the aft 
fairing compartment, inside the heat shield cavity of the aft fairing. 
There have also been reports of tube wear at the clamp location on 
additional airplanes. This proposed AD would require replacing the 
drain tube assembly of the left and right engine strut aft fairings 
with a new one which includes an integral support clamp made of nickel 
alloy 625. This proposed AD would also add airplanes to the 
applicability. We are proposing this AD to prevent failure of the drain 
tube assemblies and clamps on the aft fairings of the engine struts. 
Such failure could allow leaked flammable fluids in the drain systems 
to discharge onto the heat shields of the aft fairings of the engine 
struts, which could result in an undetected and uncontrollable fire.

DATES: We must receive comments on this proposed AD by July 27, 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: Ansel James, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 
425-917-6497; 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 proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2012-0591; 
Directorate Identifier 2012-NM-015-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

    On April 8, 2008, we issued AD 2008-08-24, Amendment 39-15478 (73 
FR 21242, April 21, 2008), for certain Model 737-600, -700, -700C, -
800, and -900 series airplanes. That AD requires replacing the drain 
tube assemblies and support clamps on the aft fairing of the engine 
struts. That AD resulted from reports of failure of the drain tube 
assembly and clamp on the aft fairings of an engine strut. We issued 
that AD to prevent failure of the drain tube assemblies and clamps on 
the aft fairings of the engine struts. Failure of the drain tube 
assemblies could allow leaked flammable fluids in the drain systems to 
discharge onto the heat shields of the aft fairings of the engine 
struts, which could result in an undetected and uncontrollable fire.

Actions Since Existing AD Was Issued

    AD 2008-08-24, Amendment 39-15478 (73 FR 21242, April 21, 2008), 
refers to Boeing Special Attention Service Bulletin 737-54-1043, dated 
May 2, 2007, as the appropriate source of service information for the 
required actions.
    Boeing then issued Special Attention Service Bulletin 737-54-1043, 
Revision 1, dated October 19, 2009, to replace the drain tube assembly 
of the engine strut aft fairing and support clamp.
    Since we issued AD 2008-08-24, Amendment 39-15478 (73 FR 21242, 
April 21, 2008), an airplane on which the actions specified in Boeing 
Special Attention Service Bulletin 737-54-1043, Revision 1, dated 
October 19, 2009, had been incorporated in production, was reported to 
have a broken drain tube assembly on the aft fairing of the left engine 
strut at the clamp support location under the aft fairing compartment, 
inside the heat shield cavity of the aft fairing (the same location 
identified in the existing AD).

[[Page 34880]]

This airplane had accumulated 4,127 total flight cycles and 6,845 total 
flight hours. There have also been reports of tube wear at the clamp 
location.
    Boeing subsequently issued Special Attention Service Bulletin 737-
54-1043, Revision 2, dated November 4, 2011, which describes procedures 
for replacing the drain tube assembly of the engine strut aft fairing 
with a new one which includes an integral support clamp made of nickel 
alloy 625.
    Boeing Special Attention Service Bulletin 737-54-1043, Revision 2, 
dated November 4, 2011, includes Model 737-900ER series airplanes, 
which were not included in Boeing Special Attention Service Bulletin 
737-54-1043, dated May 2, 2007.

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 retain none of the requirements of AD 2008-
08-24, Amendment 39-15478 (73 FR 21242, April 21, 2008). This proposed 
AD would add airplanes to the applicability statement of the existing 
AD. This proposed AD would also require accomplishing the actions 
specified in Boeing Special Attention Service Bulletin 737-54-1043, 
Revision 2, dated November 4, 2011, described in this NPRM.

Costs of Compliance

    We estimate that this proposed AD affects 1,098 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
----------------------------------------------------------------------------------------------------------------
Replacement.......................  14 work-hours x $85 per           $12,326          $13,516      $14,840,568
                                     hour = $1,190.
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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 have 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 that the 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 removing airworthiness directive 
(AD) 2008-08-24, Amendment 39-15478 (73 FR 21242, April 21, 2008), and 
adding the following new AD:

The Boeing Company: Docket No. FAA-2012-0591; Directorate Identifier 
2012-NM-015-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by July 27, 
2012.

(b) Affected ADs

    This AD supersedes AD 2008-08-24, Amendment 39-15478 (73 FR 
21242, April 21, 2008).

(c) Applicability

    This AD applies to The Boeing Company Model 737-600, -700, -
700C, -800, -900, and -900ER series airplanes; certificated in any 
category; as identified in Boeing Special Attention Service Bulletin 
737-54-1043, Revision 2, dated November 4, 2011.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 54, Nacelles/pylons.

(e) Unsafe Condition

    This AD was prompted by a report of a broken drain tube assembly 
on the aft fairing of the left engine strut at the clamp support 
location under the aft fairing compartment, inside the heat shield 
cavity of the aft fairing. There have also been reports of tube wear 
at the clamp location on additional airplanes. We are issuing this 
AD to prevent failure of the drain tube assemblies and clamps on the 
aft fairings of the engine struts. Such failure could allow leaked 
flammable fluids in the drain systems to discharge onto the heat 
shields of the aft fairings of the engine struts, which could result 
in an undetected and uncontrollable fire.

(f) Compliance

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

(g) Replacement

    Within 60 months after the effective date of this AD, replace 
the drain tube assemblies and support clamps on the aft fairing of 
the struts of engines 1 and 2 with new drain tube assemblies and 
clamps, in accordance with the Accomplishment Instructions of Boeing 
Special Attention Service Bulletin 737-54-1043, Revision 2, dated 
November 4, 2011.

(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

[[Page 34881]]

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) AMOCs approved previously in accordance with AD 2008-08-24, 
Amendment 39-15478 (73 FR 21242, April 21, 2008), are not approved 
as AMOCs with this AD.

(i) Related Information

    (1) For more information about this AD, contact Ansel James, 
Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle 
Aircraft Certification Office, 1601 Lind Avenue SW., Renton, 
Washington 98057-3356; phone: 425-917-6497; 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 May 31, 2012.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-14245 Filed 6-11-12; 8:45 am]
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