[Federal Register Volume 69, Number 219 (Monday, November 15, 2004)]
[Rules and Regulations]
[Pages 65520-65522]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-24936]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-18996; Directorate Identifier 2004-NM-40-AD; 
Amendment 39-13865; AD 2004-23-10]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Boeing Model 737-700 and -800 series airplanes. This AD 
requires doing an initial inspection for pitting and cracks of the 
lower skin panel at the lap joint; trimming the inner skin; installing 
exterior doublers; replacing the fuselage skin assembly; doing 
repetitive supplemental inspections; and repairing if necessary; as 
applicable. This AD is prompted by a report indicating that localized 
pitting in the lower skin panels was found during production on a 
limited number of airplanes. We are issuing this AD to detect and 
correct premature fatigue cracking at certain lap splice locations and 
consequent rapid decompression of the airplane.

DATES: This AD becomes effective December 20, 2004.
    The incorporation by reference of a certain publication listed in 
the AD is approved by the Director of the Federal Register as of 
December 20, 2004.

ADDRESSES: For service information identified in this AD, contact 
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-
2207. You can examine this information at the National Archives and 
Records Administration (NARA). For information on the availability of 
this material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_-register/code--of--federal--regulations/ibr--
locations.html.
    You can examine the contents of this AD docket on the Internet at 
http://dms.dot.gov, or at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street, SW., room PL-401, on 
the plaza level of the Nassif Building, Washington, DC.

FOR FURTHER INFORMATION CONTACT:
    Technical information: Sue Lucier, Aerospace Engineer, Airframe 
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind 
Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6438; 
fax (425) 917-6590.
    Plain language information: Marcia Walters, [email protected].

Examining the Docket

    The AD docket contains the proposed AD, comments, and any final 
disposition. You can examine the 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 DOT 
street address stated in the ADDRESSES section.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR Part 39 
with an AD for certain Boeing Model 737-700 and -800 series airplanes. 
That action, published in the Federal Register on September 3, 2004 (69 
FR 53855), proposed to require doing an initial inspection for pitting 
and cracks of the lower skin panel at the lap joint; trimming the inner 
skin; installing exterior doublers; replacing the fuselage skin 
assembly; doing repetitive

[[Page 65521]]

supplemental inspections; and repairing if necessary; as applicable.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. No comments have been submitted on the proposed 
AD or on the determination of the cost to the public.

Conclusion

    We have carefully reviewed the available data and determined that 
air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

    This AD will affect about 4 airplanes worldwide and 2 airplanes of 
U.S. registry. The following table provides the estimated costs to 
comply with this AD.
    The average labor rate is $65 per work hour. The cost impact of the 
AD on U.S. operators is estimated to be $83,855.

                                               Table.--Cost Impact
----------------------------------------------------------------------------------------------------------------
    For airplanes listed in the
   referenced service bulletin as                Work hours                   Parts cost          Per airplane
               group                                                                                  cost
----------------------------------------------------------------------------------------------------------------
1..................................  Inspection: 2....................  None..................              $130
                                     Modification: 38.................  105...................             2,575
2..................................  Inspection: 2....................  None..................               130
                                     Modification: 30.................  104...................             2,054
3..................................  Inspection: 2....................  None..................               130
                                     Modification: 42.................  106...................             2,836
4..................................  Repair: 920......................  16,200................            76,000
----------------------------------------------------------------------------------------------------------------

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

2004-23-10 Boeing: Amendment 39-13865. Docket No. FAA-2004-18996; 
Directorate Identifier 2004-NM-40-AD.

Effective Date

    (a) This AD becomes effective December 20, 2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 737-700 and -800 series 
airplanes, certificated in any category; having variable and serial 
numbers listed in Table 1 of this AD.

            Table 1.--Applicable Variable and Serial Numbers.
------------------------------------------------------------------------
                                                      Serial
                  Variable number                     number     Group
------------------------------------------------------------------------
YA004.............................................      27837          1
YA005.............................................      27836          2
YA201.............................................      28004          4
YC003.............................................      27977          3
------------------------------------------------------------------------

Unsafe Condition

    (d) This AD was prompted by a report indicating that localized 
pitting in the lower skin panels was found during production on a 
limited number of airplanes. We are issuing this AD to detect and 
correct premature fatigue cracking at certain lap splice locations 
and consequent rapid decompression of the airplane.

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.

Initial Inspection and/or Repair

    (f) At the applicable times specified in Table 1 of paragraph 
1.E., ``Compliance,'' of Boeing Special Attention Service Bulletin 
737-53-1256, dated September 18, 2003, do the applicable actions 
specified in Table 2 of this AD in accordance with the 
Accomplishment Instructions of the service bulletin.

               Table 2.--Initial Inspection and/or Repair
------------------------------------------------------------------------
 For airplanes identified in
  the service bulletin as--                  Requirements--
------------------------------------------------------------------------
(1) Groups 1, 2, and 3.......  Do an external ultrasonic inspection for
                                pitting and cracks of the lower skin
                                panel at the lap joint.
(2) Groups 1 and 2...........  Trim the inner skin and install two
                                exterior doublers (including related
                                investigative actions).
(3) Group 3..................  Install three exterior doublers.
(4) Group 4..................  Replace the fuselage skin assembly with a
                                new assembly.
------------------------------------------------------------------------


[[Page 65522]]

Repetitive Inspections

    (g) For Groups 1, 2, and 3 airplanes identified in Boeing 
Special Attention Service Bulletin 737-53-1256, dated September 18, 
2003: At the applicable times specified in Table 2 of paragraph 
1.E., ``Compliance,'' of the service bulletin, do the repetitive 
supplemental inspections of the lower skins and external doublers 
for discrepancies in accordance with the Accomplishment Instructions 
of the service bulletin.

Corrective Action

    (h) If any discrepancy is found during any action required by 
this AD, before further flight, repair per a method approved by the 
Manager, Seattle Aircraft Certification Office (ACO), FAA; or per 
data meeting the type certification basis of the airplane approved 
by a Boeing Company Designated Engineering Representative (DER) who 
has been authorized by the Manager, Seattle ACO, to make such 
findings. For a repair method to be approved, the approval must 
specifically reference this AD.

Alternative Methods of Compliance (AMOCs)

    (i)(1) The Manager, Seattle ACO, FAA, has the authority to 
approve AMOCs for this AD, if requested in accordance with the 
procedures found in 14 CFR 39.19.
    (2) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by a 
Boeing Company DER who has been authorized by the Manager, Seattle 
ACO, to make those findings. For a repair method to be approved, the 
approval must specifically refer to this AD.

Material Incorporated by Reference

    (j) You must use Boeing Special Attention Service Bulletin 737-
53-1256, dated September 18, 2003, to perform the actions that are 
required by this AD, unless the AD specifies otherwise. The Director 
of the Federal Register approves the incorporation by reference of 
this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 
For copies of the service information, contact Boeing Commercial 
Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. For 
information on the availability of this material at the National 
Archives and Records Administration (NARA), call (202) 741-6030, or 
go to http://www.archives.gov/federal_ register/code--of--federal--
regulations/ibr--locations.html. You may view the AD docket at the 
Docket Management Facility, U.S. Department of Transportation, 400 
Seventh Street SW, room PL-401, Nassif Building, Washington, DC.

    Issued in Renton, Washington, on November 1, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-24936 Filed 11-12-04; 8:45 am]
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