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[Federal Register Volume 79, Number 82 (Tuesday, April 29, 2014)]
[Rules and Regulations]
[Pages 23906-23908]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-08987]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0837; Directorate Identifier 2013-NM-112-AD; 
Amendment 39-17832; AD 2014-08-08]
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 737-200, -200C, -300, -400, and -500 series 
airplanes. This AD was prompted by reports of cracking found in the 
skin at the lower aft corner of the forward entry doorway on airplanes 
that do not have an airstair door cutout. This AD requires repetitive 
inspections for cracking in the lower corners of the forward entry 
doorway on airplanes that do not have an airstair door cutout, and 
repair if necessary. We are issuing this AD to detect and correct 
cracking in the lower corners of the forward entry doorway, which could 
lead to crack progression and consequent rapid decompression of the 
airplane.

DATES: This AD is effective June 3, 2014
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of June 3, 
2014.

ADDRESSES: 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. You may view this referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, WA. 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 by searching for and locating Docket No. FAA-2013-
0837; 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 Docket 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: Alan Pohl, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6450; fax: 
425-917-6590; email: alan.pohl@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to certain The Boeing Company 
Model 737-200, -200C, -300, -400, and -500 series airplanes. The NPRM 
published in the Federal Register on October 2, 2013 (78 FR 60807). The 
NPRM was prompted by reports of cracking found in the skin at the lower 
aft corner of the forward entry doorway on airplanes that do not have 
an airstair door cutout. The NPRM proposed to require repetitive 
inspections for cracking in the lower corners of the forward entry 
doorway on airplanes that do not have an airstair door cutout, and 
repair if necessary. We are issuing this AD to detect and correct 
cracking in the lower corners of the forward entry doorway, which could 
lead to crack progression and consequent rapid decompression of the 
airplane.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the proposal 
(78 FR 60807, October 2, 2013) and the FAA's response to each comment.

Support for the Proposed Requirements

    Boeing stated that it concurs with the proposed requirements.

Statement Regarding Effect of Winglets on Accomplishment of AD 
Requirements

    Aviation Partners Boeing stated that the installation of winglets 
per APB Supplemental Type Certificate (STC) ST01219SE (http://
rgl.faa.gov/Regulatory--and--Guidance--Library/rgstc.nsf/0/
be866b732f6cf31086257b9700692796/$FILE/ST01219SE.pdf) does not affect 
the accomplishment of the manufacturer's service instructions.
    We agree. We have redesignated paragraph (c) of the NPRM (78 FR 
60807, October 2, 2013) as paragraph (c)(1) and added paragraph (c)(2) 
to this final rule to state that installation of APB STC ST01219SE 
(http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/
be866b732f6cf31086257b9700692796/$FILE/ST01219SE.pdf) does not affect 
the ability to accomplish the actions required by this AD. Therefore, 
for airplanes on which APB STC ST01219SE is installed, a ``change in 
product'' alternative method of compliance (AMOC) approval request is 
not necessary to comply with the requirements of section 39.17 of the 
Federal Aviation Regulations (14 CFR 39.17).

Request To Allow Credit for Previously Accomplished Repairs

    Alaska Airlines (ASA) requested that we revise the NPRM (78 FR 
60807, October 2, 2013) to allow credit for previously accomplished 
repairs. ASA stated that it has already installed repairs in the 
specified area using FAA- and Boeing-approved data on some of its 
airplanes. ASA did not provide details for any specific repair.
    We do not agree to allow credit for unspecified repairs. ASA did 
not provide criteria for evaluating existing repairs or for 
demonstrating how such repairs would comply with the requirements of 
this AD. However, once we issue this AD, any person may request 
approval of an existing repair as an AMOC under the provisions of 
paragraph (j) of this AD. We have not changed this final rule in this 
regard.

Request To Allow Certain Terminating Repairs for Certain Airplanes

    Southwest Airlines (SWA) requested that certain structural repairs 
specified in Part 2 of the Work Instructions of Boeing Alert Service 
Bulletin 737-53A1329, dated June 4, 2013, terminate both the initial 
and repetitive inspections required by paragraph (g) of the NPRM (78 FR 
60807, October 2, 2013). SWA pointed out that Boeing

[[Page 23907]]

Alert Service Bulletin 737-53A1329, dated June 4, 2013, states that 
certain repairs provided in Part 2 of the Work Instructions terminate 
both the initial and the repetitive inspections specified in that 
service bulletin for Group 3 airplanes.
    We agree that the structural repairs specified in Part 2 of the 
Work Instructions of Boeing Alert Service Bulletin 737-53A1329, dated 
June 4, 2013, terminate both the initial and repetitive inspections 
required for Group 3 airplanes identified in that service bulletin. We 
have revised paragraph (h) of this final rule to specify that both the 
initial and repetitive inspections are terminated by the specified 
repairs for Group 3 airplanes.

Request To Consider Certain STC Modifications as an AMOC With This AD

    ASA requested that modifications per STC ST03387AT (http://
rgl.faa.gov/Regulatory--and--Guidance--Library/rgstc.nsf/0/
bd126e373ba4c5da86257a79006f31bf/$FILE/ST03387AT.pdf) and STC SA2969SO 
(http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/
2a10f5d4090a534686257a79006f0f97/$FILE/SA2969SO.pdf) be considered as 
an AMOC for the requirements of this AD. ASA noted that it has 
passenger/cargo configured airplanes that have been modified per these 
STCs.
    We disagree with the commenter's request. ASA did not demonstrate 
how these modifications would address the identified unsafe condition. 
We also need to clarify the AMOC process. AMOCs provide an alternative 
method of compliance to the methods required to be used in the 
associated AD. An AMOC is issued only after an AD has been issued and 
only after data are provided to show that the proposed solution is 
complete and addresses the unsafe condition. However, once we issue 
this AD, any person may request approval of an AMOC under the 
provisions of paragraph (j) of this AD.

Request To Delegate Repair Approval Authority to the Manufacturer

    SWA requested that AMOC authority be granted to the manufacturer 
for existing repairs approved previously using FAA Form 8100-9, 
``Statement of Compliance with Airworthiness Standards.'' SWA provided 
no justification for this request.
    We do not agree that a change to this final rule is necessary in 
this regard. Paragraph (j)(3) of this AD already delegates the 
authority to approve an AMOC for any repair required by this AD to the 
Boeing Commercial Airplanes Organization Designation Authorization, as 
long as the repair meets the certification basis of the airplane and 
the approval specifically refers to this AD. We have made no change to 
this final rule in this regard.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the changes described previously and minor editorial 
changes. We have determined that these minor changes:
     Are consistent with the intent that was proposed in the 
NPRM (78 FR 60807, October 2, 2013) for correcting the unsafe 
condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM (78 FR 60807, October 2, 2013).

Costs of Compliance

    We estimate that this AD affects 376 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                             Parts                              Cost on U.S.
              Action                      Labor cost         cost       Cost per product          operators
----------------------------------------------------------------------------------------------------------------
Inspection of the lower corners of  5 work-hours x $85          $0   $425, per inspection   $159,800, per
 the forward entry doorway (Groups   per hour = $425, per             cycle.                 inspection cycle.
 2 and 3 airplanes) \1\.             inspection cycle.
----------------------------------------------------------------------------------------------------------------
\1\ We have received no definitive data that would enable us to provide cost estimates for the inspection on
  Group 1 airplanes.

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this AD.

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:

[[Page 23908]]

    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):

2014-08-08 The Boeing Company: Amendment 39-17832; Docket No. FAA-
2013-0837; Directorate Identifier 2013-NM-112-AD.

(a) Effective Date

    This AD is effective June 3, 2014.

(b) Affected ADs

    For The Boeing Company Model 737-300, -400, and -500 series 
airplanes: Certain requirements of AD 2008-09-13, Amendment 39-15494 
(73 FR 24164, May 2, 2008), may be affected by certain requirements 
of this AD.

(c) Applicability

    (1) This AD applies to The Boeing Company Model 737-200, -200C, 
-300, -400, and -500 series airplanes, certificated in any category, 
without an airstair door cutout, as identified in Boeing Alert 
Service Bulletin 737-53A1329, dated June 4, 2013.
    (2) Installation of Supplemental Type Certificate (STC) 
ST01219SE (http://rgl.faa.gov/Regulatory--and--Guidance--Library/
rgstc.nsf/0/be866b732f6cf31086257b9700692796/$FILE/ST01219SE.pdf) 
does not affect the ability to accomplish the actions required by 
this AD. Therefore, for airplanes on which STC ST01219SE is 
installed, a ``change in product'' alternative method of compliance 
(AMOC) approval request is not necessary to comply with the 
requirements of section 39.17 of the Federal Aviation Regulations 
(14 CFR 39.17).

(d) Subject

    Air Transport Association (ATA) of America Code 53, Fuselage.

(e) Unsafe Condition

    This AD was prompted by reports of cracking found in the skin at 
the lower aft corner of the forward entry doorway on airplanes that 
do not have an airstair door cutout. We are issuing this AD to 
detect and correct cracking in the lower corners of the forward 
entry doorway, which could lead to crack progression and consequent 
rapid decompression of the airplane.

(f) Compliance

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

(g) Repetitive Inspections

    Except as provided by paragraph (i)(1) of this AD, at the 
applicable times specified in paragraph 1.E., ``Compliance,'' of 
Boeing Alert Service Bulletin 737-53A1329, dated June 4, 2013, do 
the actions specified in paragraph (g)(1) or (g)(2) of this AD, as 
applicable.
    (1) For Group 1 airplanes, as identified in Boeing Alert Service 
Bulletin 737-53A1329, dated June 4, 2013: Except as provided by 
paragraph (i)(2) of this AD, inspect the lower corners of the 
forward entry doorway for cracking, using a method approved in 
accordance with the procedures specified in paragraph (j) of this 
AD.
    (2) For Group 2 and Group 3 airplanes, as identified in Boeing 
Alert Service Bulletin 737-53A1329, dated June 4, 2013: At the 
forward entry doorway lower forward and aft corners, as applicable, 
do an internal detailed inspection of the skin assembly and bear 
strap, an internal high frequency eddy current (HFEC) inspection of 
the bear strap, and external detailed and HFEC inspections of the 
skin assembly for cracking, in accordance with Part 2 of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
53A1329, dated June 4, 2013. If no cracking is found during any 
inspection required by this paragraph: Except as provided by 
paragraph (i)(1) of this AD, repeat the applicable inspections at 
the applicable time specified in paragraph 1.E., ``Compliance,'' of 
Boeing Alert Service Bulletin 737-53A1329, dated June 4, 2013.

(h) Repair

    (1) If any cracking is found during any inspection required by 
paragraph (g) of this AD: For Group 3 airplanes with cracking at the 
aft lower corner of the forward entry doorway, before further 
flight, repair in accordance with Part 2 of the Accomplishment 
Instructions of Boeing Alert Service Bulletin 737-53A1329, dated 
June 4, 2013. Accomplishment of this repair terminates the initial 
and repetitive inspections required by this AD in the area common to 
the repair for Group 3 airplanes only. For all other cracking found, 
before further flight, repair using a method approved in accordance 
with the procedures specified in paragraph (j) of this AD.
    (2) Installation of a repair approved in accordance with 
paragraph (j) of this AD terminates the repetitive inspections 
required by this AD for the repaired area only.

(i) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Service Bulletin 737-53A1329, dated June 
4, 2013, specifies a compliance time ``after the original issue date 
of this service bulletin,'' this AD requires compliance within the 
specified compliance time after the effective date of this AD.
    (2) Although Boeing Alert Service Bulletin 737-53A1329, dated 
June 4, 2013, specifies contacting Boeing for information on certain 
inspections and repairs, this AD requires that those actions be done 
by 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, send it to the 
attention of the person identified in paragraph (k) 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.
    (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 
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 Alan Pohl, Aerospace 
Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; 
phone: 425-917-6450; fax: 425-917-6590; email: alan.pohl@faa.gov.

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Service Bulletin 737-53A1329, dated June 4, 
2013.
    (ii) Reserved.
    (3) For The Boeing Company 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 view this service information at FAA, Transport 
Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For 
information on the availability of this material at the FAA, call 
425-227-1221.
    (5) You may view this 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 April 14, 2014.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2014-08987 Filed 4-28-14; 8:45 am]
BILLING CODE 4910-13-P
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