[Federal Register Volume 70, Number 225 (Wednesday, November 23, 2005)]
[Rules and Regulations]
[Pages 70713-70715]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-23056]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-19682; Directorate Identifier 2004-NM-88-AD; 
Amendment 39-14383; AD 2005-24-03]
RIN 2120-AA64


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

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

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Boeing Model 737-600, -700, -700C, and -800 series airplanes. 
This AD requires inspecting/measuring the length of the attachment 
fasteners between the nacelle support fittings and the lower wing skin 
panels, and related investigative/corrective actions if necessary. This 
AD results from a report from the manufacturer that in production, 
during the installation of certain attachment fasteners for the nacelle 
support fittings, only one washer was installed instead of two. We are 
issuing this AD to prevent inadequate fastener clamp-up, which could 
result in cracking of the fastener holes, cracking along the lower wing 
skin panels, fuel leaking from the wing fuel tanks onto the engines, 
and possible fire.

DATES: This AD becomes effective December 28, 2005.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of December 28, 
2005.

ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street, SW., Nassif Building, 
room PL-401, Washington, DC.
    Contact Boeing Commercial Airplanes, PO Box 3707, Seattle, 
Washington 98124-2207, for service information identified in this AD.

FOR FURTHER INFORMATION CONTACT: Nancy Marsh, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6440; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Examining the Docket

    You may examine the airworthiness directive (AD) docket on the 
Internet at http://dms.dot.gov or in person at the Docket Management 
Facility office between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Management Facility office 
(telephone (800) 647-5227) is located on the plaza level of the Nassif 
Building at the street address stated in the ADDRESSES section.

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that would apply to certain Boeing Model 
737-600, -700, -700C, and -800 series airplanes. That NPRM was 
published in the Federal Register on November 24, 2004 (69 FR 68268). 
That NPRM proposed to require inspecting/measuring the length of the 
attachment fasteners between the nacelle support fittings and the lower 
wing skin panels, and related investigative/corrective actions if 
necessary.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Support for the NPRM

    One commenter supports the actions described in the NPRM.

Notice of Service Bulletin Revision

    One commenter, the manufacturer, notes that there is an error in 
the variable numbers listed in the effectivity of Boeing Service 
Bulletin 737-57-1275, dated September 4, 2003 (which was referenced as 
the appropriate source of service information for accomplishing the 
proposed actions). The commenter states that this error is corrected in 
the next revision of the service bulletin and that correcting this 
error in the service bulletin will not alter the NPRM's applicability.
    We agree with the commenter that the applicability of this AD is 
not affected by the change in variable numbers. The applicability of 
this AD refers to the airplane line numbers and not to the variable 
numbers.

[[Page 70714]]

    Since the issuance of the NPRM, Boeing has issued Service Bulletin 
737-57-1275, Revision 1, dated August 18, 2005, which contains the same 
procedures as the original issue along with the corrected variable 
numbers. Revision 1 of the service bulletin also divides the 
effectivity into four groups in order to provide clarification on the 
different fastener installation configurations. We have revised this AD 
to reference Revision 1 as the appropriate source of service 
information for accomplishing the required actions. We have also added 
paragraph (h) to this AD to give credit for actions done before the 
effective date of this AD in accordance with the original issue of the 
service bulletin.

Clarification of Sealant Specification

    One commenter notes that Figures 1 and 2 of Boeing Service Bulletin 
737-57-1275, dated September 4, 2003, specify an obsolete sealant. The 
commenter states that the ``Parts and Materials Supplied by the 
Operator'' section of the service bulletin specifies to refer to the 
Qualified Parts List (QPL) at the end of the Boeing Material 
Specification (BMS) for supplier data; however, there is no QPL for BMS 
5-26 because it is obsolete. The commenter points out that BMS 5-45 has 
superseded BMS 5-26.
    We agree with the commenter that BMS 5-45 is the correct 
specification for the sealant. Boeing Service Bulletin 737-57-1275, 
Revision 1, dated August 18, 2005, does contain the correct references 
to BMS 5-45. As stated previously, we have revised this AD to reference 
Revision 1 as the appropriate source of service information for 
accomplishing the required actions. No further work is necessary for 
airplanes on which Boeing Service Bulletin 737-57-1275, dated September 
4, 2003, was accomplished.

Request To Revise Compliance Time

    One commenter requests that we revise the compliance time specified 
in paragraph (f)(2) of the NPRM from prior to the accumulation of 
``30,000 flight cycles or 30,000 flight hours, whichever is first'' to 
prior to the accumulation of ``30,000 flight cycles or 37,000 flight 
hours, whichever is first.'' The commenter states that 15 of its 
airplanes are not scheduled for a heavy ``C'' check maintenance within 
the 30,000-flight-hour window and the proposed compliance time would 
result in unnecessary financial hardship. No technical justification 
was provided.
    We do not agree with the commenter to revise the compliance time. 
In developing an appropriate compliance time, we considered the safety 
implications, the manufacturer's recommendation, and normal maintenance 
schedules for timely accomplishment of the inspection. We have 
determined that the compliance time, as proposed, represents the 
maximum interval of time allowable for the affected airplanes to 
continue to safely operate before the inspection is done. However, 
paragraph (i) of this AD provides affected operators the opportunity to 
apply for an adjustment of the compliance time if the operator also 
presents data that justify the adjustment. We have not revised this AD 
in this regard.

Explanation of Change Made to This AD

    Boeing Commercial Airplanes has received a Delegation Option 
Authorization (DOA). We have revised this AD to delegate the authority 
to approve an alternative method of compliance for any repair required 
by this AD to an Authorized Representative for the Boeing Commercial 
Airplanes DOA rather than a Designated Engineering Representative 
(DER).

Clarification of Alternative Method of Compliance (AMOC) Paragraph

    We have revised this AD to clarify the appropriate procedure for 
notifying the principal inspector before using any approved AMOC on any 
airplane to which the AMOC applies.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    There are about 751 airplanes of the affected design in the 
worldwide fleet. The following table provides the estimated costs for 
U.S. operators to comply with this AD.

                                                                     Estimated Costs
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                                                                                                                                Number of
                                                                   Average                                        Cost per        U.S.-
                     Action                        Work hours    labor rate                 Parts                 airplane     registered    Fleet cost
                                                                  per hour                                                      airplanes
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Inspection/Measurement..........................           12           $65   Nominal.........................         $780           302      $235,560
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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 have determined that 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); 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

[[Page 70715]]

this 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, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

2005-24-03 Boeing: Amendment 39-14383. Docket No. FAA-2005-19682; 
Directorate Identifier 2004-NM-88-AD.

Effective Date

    (a) This AD becomes effective December 28, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 737-600, -700, -700C, and -
800 series airplanes; line numbers 1 through 761 inclusive, except 
for line numbers 596, 683, 742, 749, 750, 751, 754, 755, 759, and 
760; certificated in any category.

Unsafe Condition

    (d) This AD was prompted by a report from the manufacturer that 
in production, during installation of certain attachment fasteners 
for the nacelle support fittings, only one washer was installed 
instead of two. We are issuing this AD to prevent inadequate 
fastener clamp-up, which could result in cracking of the fastener 
holes, cracking along the lower wing skin panels, fuel leaking from 
the wing fuel tanks onto the engines, and possible 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.

Inspection/Measurement and Related Investigative and Corrective Actions

    (f) At the applicable time specified in paragraph (f)(1) or 
(f)(2) of this AD: Inspect/measure the length of certain attachment 
fasteners between the lower wing skin panels and the nacelle support 
fittings. Do the inspection/measurement, and all applicable related 
investigative and corrective actions, in accordance with the 
Accomplishment Instructions of Boeing Service Bulletin 737-57-1275, 
Revision 1, dated August 18, 2005, except as provided by paragraph 
(g) of this AD.
    (1) For airplanes modified by Supplemental Type Certificate 
(STC) ST00830SE as of the effective date of this AD: Prior to the 
accumulation of 25,000 total flight hours or 25,000 total flight 
cycles, whichever is first.
    (2) For airplanes not modified by STC ST00830SE as of the 
effective date of this AD: Prior to the accumulation of 30,000 total 
flight hours or 30,000 total flight cycles, whichever is first.
    (g) If accomplishing a corrective action as required by 
paragraph (f) of this AD, and the service bulletin specifies to 
contact Boeing for repair information: Before further flight, do the 
repair using a method approved in accordance with paragraph (i) of 
this AD.

Actions Accomplished According to Previous Issue of Service Bulletin

    (h) Actions accomplished before the effective date of this AD in 
accordance with Boeing Service Bulletin 737-57-1275, dated September 
4, 2003, are considered acceptable for compliance with the 
corresponding action specified in this AD.

Alternative Methods of Compliance (AMOCs)

    (i)(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.
    (2) Before using any AMOC approved in accordance with 14 CFR 
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Seattle ACO, to make those findings. For a repair 
method to be approved, the repair must meet the certification basis 
of the airplane, and the approval must specifically refer to this 
AD.

Material Incorporated by Reference

    (j) You must use Boeing Service Bulletin 737-57-1275, Revision 
1, dated August 18, 2005, to perform the actions that are required 
by this AD, unless the AD specifies otherwise. The Director of the 
Federal Register approved the incorporation by reference of this 
document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for a copy of this service information. You 
may review copies at the Docket Management Facility, U.S. Department 
of Transportation, 400 Seventh Street SW., room PL-401, Nassif 
Building, Washington, DC; on the Internet at http://dms.dot.gov; or 
at the National Archives and Records Administration (NARA). For 
information on the availability of this material at the NARA, 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 November 10, 2005.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-23056 Filed 11-22-05; 8:45 am]
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