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[Federal Register Volume 76, Number 251 (Friday, December 30, 2011)]
[Rules and Regulations]
[Pages 82111-82113]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-32678]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0996; Directorate Identifier 2011-NM-068-AD; 
Amendment 39-16899; AD 2011-26-09]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all The 
Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER 
series airplanes. This AD was prompted by reports of excessive in-
service wear damage of the thumbnail fairing edge seal, and of the 
panel rub strip and skin assembly of the fan cowl. This AD requires 
replacement of the thumbnail fairing edge seals on both sides of the 
engines with Nitronic 60 stainless steel alloy seals. We are issuing 
this AD to prevent failure of the fire seal, which could allow a fire 
in the fan compartment to spread beyond the firewall and reach the 
flammable fluid leakage zones, resulting in an uncontrolled fire.

DATES: This AD is effective February 3, 2012.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of February 3, 
2012.

ADDRESSES: 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 
me.boecom@boeing.com; Internet https:[sol][sol]www.myboeingfleet.com. 
You may review copies of the referenced service information at the FAA, 
Transport Airplane Directorate, 1601

[[Page 82112]]

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:[sol][sol]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 AD, the regulatory 
evaluation, any comments received, and other information. The address 
for the Docket Office (phone: (800) 647-5527) is Document Management 
Facility, U.S. Department of Transportation, Docket Operations, M-30, 
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Chris Parker, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 
(425) 917-6496; fax: (425) 917-6590; email: chris.r.parker@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on October 5, 2011 (76 
FR 61643). That NPRM proposed to require replacement of the thumbnail 
fairing edge seals on both sides of the engines with Nitronic 60 
stainless steel alloy seals.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We have considered the comment received. Boeing supports the 
NPRM (76 FR 61643, October 5, 2011).

Conclusion

    We reviewed the relevant data, considered the comment received, and 
determined that air safety and the public interest require adopting the 
AD as proposed.

Costs of Compliance

    We estimate that this AD affects 989 airplanes of U.S. registry. We 
estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                    Cost per       Cost on U.S.
               Action                        Labor cost           Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
Replace thumbnail faring edge seals.  6 work-hours x $85 per           $2,032           $2,542       $2,514,038
                                       hour = $510.
----------------------------------------------------------------------------------------------------------------

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

    This AD will not have federalism implications under Executive Order 
13132. This AD will 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 this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under 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.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

2011-26-09: The Boeing Company: Amendment 39-16899; Docket No. FAA-
2011-0996; Directorate Identifier 2011-NM-068-AD.

(a) Effective Date

    This AD is effective February 3, 2012.

(b) Affected ADs

    None.

(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 
737-54-1046, dated February 16, 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 reports of excessive in-service wear 
damage of the thumbnail fairing edge seal, and of the panel rub 
strip and skin assembly of the fan cowl. We are issuing this AD to 
prevent failure of the fire seal, which could allow a fire in the 
fan compartment to spread beyond the firewall and reach the 
flammable fluid leakage zones, resulting in an uncontrolled fire.

(f) Compliance

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

(g) Replace the Thumbnail Fairing Edge Seals

    Within 60 months after the effective date of this AD, replace 
the thumbnail fairing edge seals, on both the left side and the 
right side of engine 1 and engine 2, with new Nitronic 60 stainless 
steel alloy seals, in accordance

[[Page 82113]]

with the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 737-54-1046, dated February 16, 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 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: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (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.

(i) Related Information

    For more information about this AD, contact Chris Parker, 
Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle 
Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton, 
Washington 98057-3356; phone: (425) 917-6496; fax: (425) 917-6590; 
email: chris.r.parker@faa.gov.

(j) Material Incorporated by Reference

    (1) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference (IBR) under 5 U.S.C. 552(a) and 1 CFR part 51 of the 
following service information on the date specified:
    (i) Boeing Special Attention Service Bulletin 737-54-1046, dated 
February 16, 2011.
    (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 
me.boecom@boeing.com; Internet https://www.myboeingfleet.com.
    (3) You may review copies of the service information at the FAA, 
Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, 
Washington 98057-3356. For information on the availability of this 
material at the FAA, call (425) 227-1221.
    (4) You may also review copies of the service information that 
is incorporated by reference at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at an NARA facility, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html

    Issued in Renton, Washington, on December 13, 2011.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-32678 Filed 12-29-11; 8:45 am]
BILLING CODE 4910-13-P
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