[Federal Register Volume 73, Number 27 (Friday, February 8, 2008)]
[Proposed Rules]
[Pages 7488-7489]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-2353]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0149; Directorate Identifier 2007-NM-319-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-100, -200, -200C, -
300, -400, and -500 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 
certain Boeing Model 737-100, -200, -200C, -300, -400, and -500 series 
airplanes. This proposed AD would require replacing the existing 
straight-to-90-degree hose assembly for the Lavatory ``A'' water 
supply. The replacement is a new straight hose assembly and a separate 
90-degree elbow fitting. This proposed AD results from a report of a 
separated hose assembly for the passenger water system. We are 
proposing this AD to prevent a water leak into the flight deck ceiling, 
which could result in an electrical short and possible loss of several 
functions essential to safe flight.

DATES: We must receive comments on this proposed AD by March 24, 2008.

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: Marcia Smith, Aerospace Engineer, 
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; telephone (425) 917-6484; 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-2008-0149; 
Directorate Identifier 2007-NM-319-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 a separated hose assembly for the 
passenger water system. The hose assembly supplies potable water 
through a 90-degree end fitting to Lavatory ``A.'' The break occurred 
at the 90-degree end fitting when the elbow separated at a soldered 
joint adjacent to the hose assembly sleeve. The break was located just 
above and inside the flight deck entry door, and resulted in water 
spilling into the flight deck ceiling, which affected various radios 
and the Aircraft Communications Addressing and Reporting System (ACARS) 
and caused them to become inoperative. These affected parts had to be 
replaced due to water damage. An analysis of the broken hose assembly 
showed signs of previous small leaks. It was concluded that an 
incompletely soldered joint failed and consequently separated. A broken 
hose assembly in this location, if not corrected, could leak into the 
flight deck ceiling and result in an electrical short and possible loss 
of several functions essential to safe flight.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 737-38A1054, dated 
August 23, 2007. The service bulletin describes procedures for 
replacing the existing straight-to-90-degree hose assembly for the 
Lavatory ``A'' water supply. The replacement is a new straight hose 
assembly and a separate 90-degree elbow fitting.

FAA's Determination and Requirements of This Proposed AD

    We are proposing this AD because we evaluated all relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other airplanes of the same type design. 
This proposed AD would require accomplishing the actions specified in 
the service information described previously.

Costs of Compliance

    We estimate that this proposed AD would affect 779 airplanes of 
U.S. registry. We also estimate that it would take between 4 and 7 
work-hours per airplane to comply with this proposed AD, depending on 
the airplane configuration. The average labor rate is $80 per work-
hour. Required parts would cost about $400 per product. Based on these 
figures, we estimate the

[[Page 7489]]

cost of this proposed AD to the U.S. operators to be between $560,880 
and $747,840, or between $720 and $960 per product.

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), 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.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

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 FAA amends Sec.  39.13 by adding the following new AD:

Boeing: Docket No. FAA-2008-0149; Directorate Identifier 2007-NM-
319-AD.

Comments Due Date

    (a) We must receive comments by March 24, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Model 737-100, -200, -200C, -300, -400, 
and -500 series airplanes, certificated in any category; as 
identified in Boeing Alert Service Bulletin 737-38A1054, dated 
August 23, 2007.

Unsafe Condition

    (d) This AD results from a report of a separated hose assembly 
for the passenger water system. We are issuing this AD to prevent a 
water leak into the flight deck ceiling, which could result in an 
electrical short and possible loss of several functions essential to 
safe flight.

Compliance

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

Replacement

    (f) Within 60 months after the effective date of this AD, 
replace the existing straight-to-90-degree hose assembly for the 
Lavatory ``A'' water supply with a new straight hose assembly and a 
separate 90-degree elbow fitting, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
38A1054, dated August 23, 2007.

Parts Installation

    (g) As of the effective date of this AD, any hose assembly part 
having a part number identified in Table 1 of this AD must not be 
used in any location that is subject to the requirements of this AD. 
However, those parts may be used in other locations if not otherwise 
prohibited.

              Table 1.--Spare Parts Prohibited for This AD
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  Airplane group identified in Boeing
  Alert Service Bulletin 737-38A1054,           Existing part Nos.
         dated August 23, 2007
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1 and 2................................  10-61998-430, AS4471-08-0401,
                                          or AS4471-08-0404.
3......................................  10-61998-25 or 10-60871-125.
4......................................  10-61998-31 or 10-60871-139.
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Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, ATTN: Marcia Smith, Aerospace Engineer, Cabin Safety and 
Environmental Systems Branch, ANM-150S, 1601 Lind Avenue, SW., 
Renton, Washington 98057-3356; telephone (425) 917-6484; fax (425) 
917-6590; has the authority to approve AMOCs for this AD, if 
requested using 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 January 31, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E8-2353 Filed 2-7-08; 8:45 am]
BILLING CODE 4910-13-P