

[Federal Register: October 17, 2007 (Volume 72, Number 200)]
[Proposed Rules]               
[Page 58773-58774]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr17oc07-15]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-0049; Directorate Identifier 2007-NM-168-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 737-600, -700, -700C, -
800, and -900 Series Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Boeing Model 737-600, -700, -700C, -800, and -900 series 
airplanes. This proposed AD would require replacing the drain tube 
assemblies and support clamps on the aft fairings of the engine struts. 
This proposed AD results from reports of failure of the drain tube 
assembly and clamp on the aft fairings of an engine strut. We are 
proposing this AD to prevent failure of the drain tube assemblies and 
clamps on the aft fairings of the engine struts. Such a failure could 
allow leaked flammable fluids in the drain systems to discharge on to 
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 December 3, 
2007.

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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

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 (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Kathrine Rask, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone 
(425) 917-6505; fax (425) 917-6590.

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-2007-0049; 
Directorate Identifier 2007-NM-168-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 failure of the drain tube assembly and 
support clamp on the aft fairing of an engine strut. In most of the 
reports, the failure occurred at the brazed joint between the tube and 
the drain cast fitting. Failure of the drain tube assembly and support 
clamp on the aft fairing of an engine strut, if not corrected, could 
allow leaked flammable fluids in the drain system to discharge on to 
the heat shield of the aft fairing of an engine strut, which may result 
in an undetected and uncontrollable fire.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 737-54-
1043, dated May 2, 2007. The service information describes procedures 
for replacing the drain tube assemblies and support clamps on the aft 
fairing of the struts of the number 1 and number 2 engines with new 
drain tube assemblies and new support clamps. Accomplishing the actions 
specified in the service information is intended to adequately address 
the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other airplanes 
of this same type design. For this reason, we are proposing this AD, 
which would require accomplishing the actions specified in the service 
information described previously.

Costs of Compliance

    There are about 2,058 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 721 airplanes of 
U.S. registry. The proposed actions would take about 4 work hours per 
airplane, at an average labor rate of $80 per work hour. Required parts 
would cost about $2,351 per airplane. Based on these figures, the 
estimated cost of the proposed AD for U.S. operators is $1,925,791, or 
$2,671 per airplane.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I,

[[Page 58774]]

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); and
    3. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, 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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2007-0049; Directorate Identifier 2007-NM-
168-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by December 
3, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 737-600, -700, -700C, -800, 
and -900 series airplanes, certificated in any category; as 
identified in Boeing Special Attention Service Bulletin 737-54-1043, 
dated May 2, 2007.

Unsafe Condition

    (d) This AD results from reports of failure of the drain tube 
assembly and support clamp on the aft fairing of an engine strut. We 
are issuing this AD to prevent failure of the drain tube assemblies 
and clamps on the aft fairings of the struts of the number 1 and 
number 2 engines. Such a failure could allow leaked flammable fluids 
in the drain systems to discharge on to the heat shields of the aft 
fairings of the engine struts, which could result in an undetected 
and uncontrollable fire.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Replacement

    (f) Within 60 months after the effective date of this AD, remove 
the drain tube assemblies and support clamps on the aft fairing of 
the struts of engine number 1 and engine number 2. These are to be 
replaced with new drain tube assemblies and clamps, in accordance 
with the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 737-54-1043, dated May 2, 2007.

Alternative Methods of Compliance (AMOCs)

    (g)(1) The Manager, Seattle Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.

    Issued in Renton, Washington, on October 9, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E7-20469 Filed 10-16-07; 8:45 am]

BILLING CODE 4910-13-P
