
[Federal Register: January 12, 2009 (Volume 74, Number 7)]
[Proposed Rules]               
[Page 1158-1159]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12ja09-12]                         


[[Page 1158]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-1362; Directorate Identifier 2008-NM-150-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 747-200C and 747-200F 
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 747-200C and 747-200F series airplanes. This 
proposed AD would require installing larger moisture shrouds and 
additional drain lines in the electrical/electronic equipment center. 
This proposed AD results from reports of water contamination in the 
electrical/electronic units in the main equipment center. We are 
proposing this AD to prevent water contamination in the electrical/
electronic units in the main equipment center, which could result in an 
electrical short and potential loss of several functions essential for 
safe flight.

DATES: We must receive comments on this proposed AD by February 26, 
2009.

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; 
telephone 206-544-9990; fax 206-766-5682; e-mail DDCS@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 or 
425-227-1152.

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-2008-1362; 
Directorate Identifier 2008-NM-150-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 water contamination in the electrical/
electronic units in the main equipment center. Loading cargo in rain or 
snow conditions can allow a large amount of water into the airplane on 
the cargo or open main deck doors. The water can spill onto the main 
deck cargo floor and flow through the power drive units (PDUs). If the 
amount of water exceeds the drain capacity of the PDUs located above 
the main equipment center, water can spill onto the electrical/
electronic units. Water contamination in the electrical/electronic 
units in the main equipment center could result in an electrical short 
and potential loss of several functions essential for safe flight.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 747-25A3431, dated 
March 6, 2008. This service bulletin describes procedures for 
installing larger moisture shrouds and additional drain lines in the 
electrical/electronic equipment center that provide protection from 
water contamination in the main equipment center. The procedures 
include:
     Changing the PDU drain tubes;
     Changing the pitot static tubes;
     Replacing moisture curtains and support brackets;
     Reworking base line (BL) 11 intercostals;
     Installing new moisture shrouds; and
     Relocating the wire bundle, lights, ground bracket, and 
disconnect bracket of the main equipment center.
    Boeing Alert Service Bulletin 747-25A3430, dated February 15, 2007, 
is necessary to be accomplished prior to or concurrent with Boeing 
Alert Service Bulletin 747-25A3431. Boeing Alert Service Bulletin 747-
25A3430 describes procedures for installing protective moisture 
curtains in the main equipment center.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition.

Related AD

    AD 2007-26-03, amendment 39-15305 (72 FR 71218, December 17, 2007), 
applies to the airplanes affected by this NPRM. That AD requires, among 
other actions, installation of mounting brackets, support angles, and 
moisture curtains in the main equipment center in accordance with 
Boeing Alert Service Bulletin 747-25A3430.

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 products 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 25 airplanes of U.S. 
registry. The following table provides the estimated costs for U.S. 
operators to comply with this proposed AD.

[[Page 1159]]



                                                                     Estimated Costs
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                                                                                                                        Number of
                                                              Average                                                     U.S.-
              Action                      Work hours        labor rate           Parts            Cost per product     registered        Fleet cost
                                                             per hour                                                   airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Installation......................  Up to 75.............          $80   Up to $28,405........  Up to $34,405.......           25   Up to $860,125.
--------------------------------------------------------------------------------------------------------------------------------------------------------

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, 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 AD:

Boeing: Docket No. FAA-2008-1362; Directorate Identifier 2008-NM-
150-AD.

Comments Due Date

    (a) We must receive comments by February 26, 2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 747-200C and 747-200F series 
airplanes, certificated in any category; as identified in Boeing 
Alert Service Bulletin 747-25A3431, dated March 6, 2008.

Unsafe Condition

    (d) This AD results from reports of water contamination in the 
electrical/electronic units in the main equipment center. We are 
issuing this AD to prevent water contamination in the electrical/
electronic units in the main equipment center, which could result in 
an electrical short and potential loss of several functions 
essential for safe flight.

Compliance

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

Installation

    (f) Within 72 months after the effective date of this AD, 
install larger moisture shrouds and additional drain lines, by doing 
all the applicable actions specified in the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-25A3431, dated 
March 6, 2008.

Prior or Concurrent Action

    (g) Prior to or concurrently with accomplishing the actions 
required by paragraph (f) of this AD: Install protective moisture 
curtains in the main equipment center in accordance with Boeing 
Alert Service Bulletin 747-25A3430, dated February 15, 2007.

    Note 1: The installation required by paragraph (g) of this AD is 
also required by paragraph (f) of AD 2007-26-03, amendment 39-15305, 
for Boeing Model 747-200C and -200F series airplanes.

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, FAA, Seattle Aircraft 
Certification Office, 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 December 18, 2008.
Stephen P. Boyd,
Assistant Manager, Transport Airplane Directorate, Aircraft 
Certification Service.
[FR Doc. E9-312 Filed 1-9-09; 8:45 am]

BILLING CODE 4910-13-P
