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[Federal Register Volume 77, Number 157 (Tuesday, August 14, 2012)]
[Rules and Regulations]
[Pages 48423-48425]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-19423]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0336; Directorate Identifier 2011-NM-213-AD; 
Amendment 39-17154; AD 2012-16-07]
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 certain 
The Boeing Company Model 737-500 series airplanes. This AD was prompted 
by reports of chem-mill step cracking on the aft lower lobe fuselage 
skins. This AD requires inspections of the fuselage skin at the chem-
mill steps, and repair if necessary. We are issuing this AD to detect 
and correct cracking on the aft lower lobe fuselage skins, which could 
result in decompression of the airplane.

DATES: This AD is effective September 18, 2012.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of September 18, 
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; 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.

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 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: Wayne Lockett, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 425-
917-6447; fax: 425-917-6590; email: wayne.lockett@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 published in the Federal Register on April 17, 2012 (77 FR 
22686). That NPRM proposed to require inspections of the fuselage skin 
at the chem-mill steps, and repair if necessary.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We have considered the comment received. Boeing supports the 
NPRM (77 FR 22686, April 17, 2012).

Clarification of Terms in the Relevant Service Information Section of 
the NPRM (77 FR 22686, April 17, 2012)

    The Relevant Service Information section of the NPRM (77 FR 22686, 
April 17, 2012) specified that ``Related investigative actions'' and 
``corrective actions'' are those actions specified in the service 
information that are necessary to address the identified unsafe 
condition. Those ``necessary'' actions are applicable to particular 
configurations and conditions. ``Related investigative actions'' are 
those actions that are identified as follow-on actions that are: (1) 
Related to the required action, and (2) are on-condition actions that 
further investigate the nature of any condition found. Related 
investigative actions could include, for example, inspections and 
operational tests. ``Corrective actions'' are those actions that are 
on-condition actions that correct or address any condition found. 
Corrective actions could include, for example, repairs, removal and 
replacement, and modifications.

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--with minor editorial changes. We have determined that 
these minor changes:
     Are consistent with the intent that was proposed in the 
NPRM (77 FR 22686, April 17, 2012) for correcting the unsafe condition; 
and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM (77 FR 22686, April 17, 2012).

Costs of Compliance

    We estimate that this AD affects 91 airplanes of U.S. registry. We 
estimate the following costs to comply with this AD:

[[Page 48424]]

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                  Cost on U.S.
             Action                     Labor cost           Parts cost     Cost per product       operators
----------------------------------------------------------------------------------------------------------------
Inspections....................  23 work-hours x $85 per              $0   $1,955 per          $177,905 per
                                  hour = $1,955 per                         inspection cycle.   inspection
                                  inspection cycle.                                             cycle.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary corrective 
actions that would be required based on the results of the inspection. 
We have no way of determining the number of aircraft that might need 
these corrective actions:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                   Action                                 Labor cost                Parts cost        product
----------------------------------------------------------------------------------------------------------------
Inspection.................................  2 work-hours x $85 per hour = $170.              $0            $170
Repair.....................................  7 work-hours x $85 per hour = $595.               0             595
----------------------------------------------------------------------------------------------------------------

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):

2012-16-07 The Boeing Company: Amendment 39-17154; Docket No. FAA-
2012-0336; Directorate Identifier 2011-NM-213-AD.

(a) Effective Date

    This AD is effective September 18, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 737-500 series 
airplanes, certificated in any category, as identified in Boeing 
Special Attention Service Bulletin 737-53-1315, dated July 29, 2011.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 53, Fuselage.

(e) Unsafe Condition

    This AD was prompted by reports of chem-mill step cracking on 
the aft lower lobe fuselage skins. We are issuing this AD to detect 
and correct cracking on the aft lower lobe fuselage skins, which 
could result in decompression of the airplane.

(f) Compliance

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

(g) Inspection

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Special Attention Service Bulletin 737-53-
1315, dated July 29, 2011, except as required by paragraph (i)(1) of 
this AD: Do an external detailed inspection; and, as applicable, do 
an external or internal subsurface eddy current, magneto optic 
imager, or C-scan inspection; to detect cracks in the fuselage skin 
at the chem-mill steps; in accordance with the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 737-53-
1315, dated July 29, 2011. Repeat the inspections thereafter at the 
applicable times specified in paragraph 1.E., ``Compliance,'' of 
Boeing Special Attention Service Bulletin 737-53-1315, dated July 
29, 2011.

(h) Repair

    If any crack is found during any inspection required by 
paragraph (g) of this AD: At the applicable times specified in 
paragraph 1.E., ``Compliance,'' of Boeing Special Attention Service 
Bulletin 737-53-1315, dated July 29, 2011, do all the actions 
specified in either paragraph (h)(1) or (h)(2) of this AD.
    (1) Do a time-limited repair; followed by applicable related 
investigative actions, corrective actions, and making the time-
limited repair permanent; in accordance with Boeing Special 
Attention Service Bulletin 737-53-1315, dated July 29, 2011, except 
as required by paragraph (i)(2) of this AD.
    (2) Do a permanent repair, including a detailed inspection of 
the bonded doubler for disbonding and a high frequency eddy current 
inspection for cracks of the bonded doubler, in accordance with 
Boeing Special Attention Service Bulletin 737-53-1315, dated July 
29, 2011. Repair any cracks and disbonding before further flight, in 
accordance with Boeing Special Attention Service Bulletin 737-53-
1315, dated July 29, 2011, except as required by paragraph (i)(2) of 
this AD. Accomplishment of the permanent repair terminates the 
repetitive inspections required by this AD for the area(s) of the 
repair only.

[[Page 48425]]

(i) Exceptions to Service Bulletin Specifications

    The exceptions specified in paragraphs (i)(1) and (i)(2) of this 
AD apply to this AD.
    (1) Where Boeing Special Attention Service Bulletin 737-53-1315, 
dated July 29, 2011, specifies a compliance time after ``the date of 
this service bulletin,'' this AD requires compliance within the 
specified compliance time after the effective date of this AD.
    (2) Where Boeing Special Attention Service Bulletin 737-53-1315, 
dated July 29, 2011, specifies to contact Boeing for repair 
instructions: Before further flight, repair using a method approved 
in accordance with the procedures specified in paragraph (j) of this 
AD.

(j) 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, it 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.
    (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 the 
Boeing Commercial Airplanes Organization Designation Authorization 
(ODA) that 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.

(k) Related Information

    For more information about this AD, contact Wayne Lockett, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office (ACO), 1601 Lind Avenue SW., Renton, Washington 
98057-3356; phone: 425-917-6447; fax: 425-917-6590; email: 
wayne.lockett@faa.gov.

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) under 5 U.S.C. 552(a) and 1 CFR 
part 51.
    (2) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Special Attention Service Bulletin 737-53-1315, dated 
July 29, 2011.
    (ii) Reserved.
    (3) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com.
    (4) You may review copies of the service information at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, 
Washington 98057-3356. For information on the availability of this 
material at the FAA call 425-227-1221.
    (5) 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 NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on July 31, 2012.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-19423 Filed 8-13-12; 8:45 am]
BILLING CODE 4910-13-P
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