
[Federal Register: September 25, 2009 (Volume 74, Number 185)]
[Proposed Rules]               
[Page 48882-48884]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr25se09-24]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0376; Directorate Identifier 2007-NM-322-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 747-100, 747-200B, 747-
300, and 747SR Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for certain Boeing Model 747-100, 747-200B, 747-300, and 747SR 
series airplanes. The original NPRM proposed to require installation of 
a closeout panel and moisture curtains for the main equipment center. 
The original NPRM also proposed to require changing the drain tubes for 
the power drive units (PDU) and the pitot static tubes and installing 
larger moisture shrouds. The original NPRM resulted from a report of 
water contamination in the electrical and electronic units in the main 
equipment center. This action revises the original NPRM by adding 
airplanes to the applicability and removing certain others, and 
removing certain requirements. We are proposing this supplemental NPRM 
to prevent the malfunction of one or more electrical and electronic 
units in the main equipment center, which could adversely affect the 
airplane's continued safe flight.

DATES: We must receive comments on this supplemental NPRM by October 
20, 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 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; 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 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-2008-0376; 
Directorate Identifier 2007-NM-322-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 issued a notice of proposed rulemaking (NPRM) (the ``original 
NPRM'') to amend 14 CFR part 39 to include an airworthiness directive 
(AD) that would apply to certain Boeing Model 747-100, 747-200B, 747-
300, and 747SR series airplanes. That original NPRM was published in 
the Federal Register on April 1, 2008 (73 FR 17258). The original NPRM 
proposed to require installation of a closeout panel and moisture 
curtains for the main equipment center. The original NPRM also proposed 
to require changing the drain tubes for the power drive units and the 
pitot static tubes and installing larger moisture shrouds.

Actions Since Original NPRM Was Issued

    Since we issued the original NPRM, we have reviewed a new revision 
of Boeing Alert Service Bulletin 747-25A3368. The original NPRM 
referred to Boeing Alert Service Bulletin 747-25A3368, Revision 1, 
dated June 25, 2007, as the appropriate source of service information 
for installing a closeout panel and moisture curtains. We have reviewed 
Boeing Service Bulletin 747-25A3368, Revision 2, dated June 12, 2008. 
Revision 2 adds instructions to fabricate parts. In addition, the 
effectivity of the service bulletin changed, adding 14 airplanes and 
removing 3 airplanes.
    We have revised paragraph (f) of the original NPRM (which is now 
paragraph (g) of this supplemental NPRM) to refer

[[Page 48883]]

to Boeing Service Bulletin 747-25A3368, Revision 2, dated June 12, 
2008. We have also revised paragraph (h) of this supplemental NPRM to 
clarify the additional work that must be done if actions have been 
accomplished in accordance with the original issue of the service 
bulletin. We have also added a new paragraph (i) to this supplemental 
NPRM to allow credit for actions accomplished in accordance with 
Revision 1 of the service bulletin. We have reidentified the subsequent 
paragraphs accordingly.

Removal of Requirement To Install Larger Moisture Shrouds and 
Additional Drain Lines

    The original NPRM referred to Boeing Alert Service Bulletin 747-
25A3346, dated September 13, 2007, as the source of information for 
changing the PDU drain tubes and pitot static tubes, and installing 
larger moisture shrouds. We have deleted all reference to Boeing Alert 
Service Bulletin 747-25A3346 because Boeing is currently revising that 
service bulletin, and waiting for the revision would prevent mandating 
the interim solution in a timely manner. Boeing Alert Service Bulletin 
747-25A3346 currently provides instructions that do not work for 
installing some of the drain lines because the airplanes do not have 
the configuration that Boeing expected. Therefore, we deleted reference 
to Boeing Alert Service Bulletin 747-25A3346, dated September 13, 2007, 
from the applicability statement of the original NPRM. We also deleted 
the requirement to install the larger moisture shrouds and additional 
drain lines in paragraph (g) of the original NPRM, and we deleted Note 
2 of the original NPRM. As a result, this proposed AD action is 
interim, and we may require a final action when we approve the revised 
service information.

Explanation of Additional Paragraph in the Supplemental NPRM

    We have added a new paragraph (d) to this supplemental NPRM to 
provide Air Transport Association (ATA) of America subject code 25: 
Equipment/furnishings. This code is added to make the format of this 
supplemental NPRM parallel with other new AD actions. We have 
reidentified subsequent paragraphs accordingly.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

    We are proposing this supplemental NPRM because we evaluated all 
pertinent information and determined an unsafe condition exists and is 
likely to exist or develop on other products of the same type design. 
Certain changes described above expand the scope of the original NPRM. 
As a result, we have determined that it is necessary to reopen the 
comment period to provide additional opportunity for the public to 
comment on this supplemental NPRM.

Interim Action

    We consider this supplemental NPRM interim action. The manufacturer 
is currently developing a modification that will address the unsafe 
condition identified in this AD. Once this modification is developed, 
approved, and available, we might consider additional rulemaking.

Costs of Compliance

    We estimate that this proposed AD would affect 47 airplanes of U.S. 
registry. The following table provides the estimated costs, at an 
average labor rate of $80 per work hour, for U.S. operators to comply 
with this proposed AD.

                                                 Estimated Costs
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                                                                                 Number of U.S.-
           Action                Work hours         Parts           Cost per       registered       Fleet cost
                                                                    product         airplanes
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Installation................  Up to 10.......  Up to $11,672..  Up to $12,472..              47  Up to $586,184.
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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 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-2008-0376; Directorate Identifier 2007-NM-
322-AD.

Comments Due Date

    (a) We must receive comments by October 20, 2009.

[[Page 48884]]

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 747-100, 747-200B, 747-300, 
and 747SR series airplanes, certificated in any category; as 
identified in Boeing Service Bulletin 747-25A3368, Revision 2, dated 
June 12, 2008.

    Note 1: The affected airplanes are those that have been 
converted by Boeing to the Boeing Special Freighter configuration.

Subject

    (d) Air Transport Association (ATA) of America Code 25: 
Equipment/furnishings.

Unsafe Condition

    (e) This AD results from a report of water contamination in the 
electrical and electronic units in the main equipment center. We are 
issuing this AD to prevent the malfunction of one or more electrical 
and electronic units in the main equipment center, which could 
adversely affect the airplane's continued safe flight.

Compliance

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

Install the Closeout Panel and Moisture Curtains

    (g) Within 24 months after the effective date of this AD, 
install the closeout panel and moisture curtains for the main 
equipment center, by accomplishing all of the applicable actions 
specified in the Accomplishment Instructions of Boeing Service 
Bulletin 747-25A3368, Revision 2, dated June 12, 2008.

Credit for Actions Done According to Previous Issue of the Service 
Bulletin

    (h) Actions done before the effective date of this AD in 
accordance with the Accomplishment Instructions in Boeing Alert 
Service Bulletin 747-25A3368, dated August 25, 2005, are acceptable 
for compliance with the corresponding actions required by paragraph 
(g) of this AD, provided that the additional work specified in the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
25A3368, Revision 1, dated June 25, 2007; or Revision 2, dated June 
12, 2008; is accomplished. The additional work required is to cap 
seal all rivets fastening the mounting base assembly to the moisture 
shroud as given in Figure 10 in Boeing Alert Service Bulletin 747-
25A3368, Revision 2, dated June 12, 2008, and to fill any unused 
pilot holes in the mounting base assembly in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
25A3368, Revision 2, dated June 12, 2008; or cap seal all rivets 
fastening the mounting base assembly to the moisture shroud as given 
in Figure 10 of Boeing Alert Service Bulletin 747-25A3368, Revision 
1, dated June 25, 2007, and to fill any unused pilot holes in the 
mounting base assembly in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-25A3368, Revision 
1, dated June 25, 2007.
    (i) Actions done before the effective date of this AD in 
accordance with Boeing Alert Service Bulletin 747-25A3368, Revision 
1, dated June 25, 2007, are acceptable for compliance with the 
corresponding actions required by paragraph (g) of this AD.

Alternative Methods of Compliance (AMOCs)

    (j)(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. Send information to 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. Or, e-mail information 
to 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (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 principal maintenance inspector (PMI) or 
principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.

    Issued in Renton, Washington, on September 16, 2009.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E9-23190 Filed 9-24-09; 8:45 am]

BILLING CODE 4910-13-P
