```

[Federal Register Volume 81, Number 196 (Tuesday, October 11, 2016)]
[Rules and Regulations]
[Pages 70011-70013]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-24197]

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-5042; Directorate Identifier 2015-NM-140-AD; 
Amendment 39-18680; AD 2016-20-14]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

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 an evaluation by the design approval 
holder (DAH) indicating that certain fastener locations in the window 
corner surround structure are subject to widespread fatigue damage 
(WFD). This AD requires repetitive high frequency eddy current (HFEC) 
inspections for cracking in certain fastener locations in the window 
corner surround structure, and repair if necessary. We are issuing this 
AD to detect and correct fatigue cracking around certain fastener 
locations that could cause multiple window corner skin cracks, which 
could result in rapid decompression and consequent loss of structural 
integrity of the airplane.

DATES: This AD is effective November 15, 2016.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of November 15, 
2016.

ADDRESSES: For service information identified in this final rule, 
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. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
5042.

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-2016-
5042; 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: Gaetano Settineri, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6577; fax: 425-917-6590; email: gaetano.settineri@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 all The Boeing Company 
Model 737-600, -700, -700C, -800, -900 and -900ER series airplanes. The 
NPRM published in the Federal Register on April 5, 2016 (81 FR 19512) 
(``the NPRM''). The NPRM was prompted by an evaluation by the DAH 
indicating that certain fastener locations in the window corner 
surround structure are subject to WFD. The NPRM proposed to require 
repetitive HFEC inspections for cracking in certain fastener locations 
in the window corner surround structure, and repair if necessary. We 
are issuing this AD to detect and correct fatigue cracking around 
certain fastener locations that could cause multiple window corner skin 
cracks, which could result in rapid decompression and consequent loss 
of structural integrity of the airplane.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Support for the NPRM

    Boeing and the Airline Pilots Association, International supported 
the content of the NPRM.

Effect of Winglets on Accomplishment of the Proposed Actions

    Aviation Partners Boeing stated that accomplishing the supplemental 
type certificate (STC) ST00830SE does not affect compliance with the 
actions specified in the NPRM.
    We agree with the commenter. We have redesignated paragraph (c) as 
(c)(1) and added a new paragraph (c)(2) to this AD to state that 
installation of STC ST00830SE does not affect the ability to accomplish 
the actions required by this final rule. Therefore, for airplanes on 
which STC ST00830SE is installed, a ``change in product'' alternative 
method of compliance (AMOC) approval request is not necessary to comply 
with the requirements of 14 CFR 39.17.

Request for Clarification of Extent of Boeing Organization Designation 
Authority (ODA)

    Southwest Airlines (SWA) asked for clarification that the Boeing 
ODA identified in paragraph (i)(3) of the proposed AD can provide an 
AMOC for any ``repair, modification, or alteration'' that includes the 
authority to approve existing repairs in the inspection area that 
inhibit accomplishment of the AD requirements as terminating action to 
paragraph (g) of the proposed AD. SWA also asked if the ODA has the 
authority to provide alternative inspection procedures for repaired 
areas where the inspection in paragraph (g) of the proposed AD cannot 
be accomplished. Additionally, SWA asked that we clarify that the 
Boeing ODA identified in paragraph (i)(3) of the proposed AD is able to 
issue an AMOC to the proposed AD for an existing repair at the S-14 lap 
joint (where the location of the repair inhibits accomplishing the 
initial inspection), provided the repair was approved by any FAA 
designation authority, and there is a minimum of three fastener rows 
above and below the lap joint. SWA stated that neither Boeing Alert 
Service Bulletin 737-53A1351, dated July 8, 2015, nor the NPRM clearly 
state how to address existing repairs that prevent

[[Page 70012]]

accomplishment of the inspections specified in paragraph (g) of the 
proposed AD.
    We agree with the commenter that clarification of the extent of the 
authority of the Boeing ODA is necessary. The Boeing ODA has the 
authority to evaluate existing repairs and provide alternative 
inspection programs in the repaired area, including authority to 
approve alternative inspections as AMOCs if needed.
    We infer that SWA is also asking if the Boeing ODA can issue a 
global AMOC for the referenced repair at the S-14 lap joint. The Boeing 
ODA does not have the authority to approve global AMOCs. In addition, 
we have not received any information from Boeing that defines such a 
repair that would be considered for a global AMOC. If Boeing provides 
supporting data, we will evaluate the data to determine if that repair 
and any associated inspections provide an acceptable level of safety 
for such an AMOC. We have not changed this AD in this regard.

Change to This AD

    We have determined that the end level effect of the unsafe 
condition in the NPRM should be changed to more closely match the 
service information. Therefore, we have changed ``. . . reduced 
structural integrity'' to ``. . . loss of structural integrity'' in the 
SUMMARY and SUPPLEMENTARY INFORMATION sections and in paragraph (e) of 
this AD accordingly.

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 for correcting the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 737-53A1351, dated July 
8, 2015. The service information describes procedures for HFEC 
inspections and repair for cracking in certain fastener locations in 
the window corner surround structure. This service information is 
reasonably available because the interested parties have access to it 
through their normal course of business or by the means identified in 
the ADDRESSES section.

Costs of Compliance

    We estimate that this AD affects 1,528 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Inspection.......................  38 work-hours x $85              $0  $3,230 per           $4,935,440 per
                                    per hour = $3,230                    inspection cycle.    inspection cycle
                                    per inspection
                                    cycle.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that will 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:

    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):

2016-20-14 The Boeing Company: Amendment 39-18680; FAA-2016-5042; 
Directorate Identifier 2015-NM-140-AD.

(a) Effective Date

    This AD is effective November 15, 2016.

(b) Affected ADs

    None.

(c) Applicability

    (1) This AD applies to all The Boeing Company Model 737-600, -
700, -700C, -800, -900 and -900ER series airplanes, certificated in 
any category.
    (2) Installation of Supplemental Type Certificate (STC) 
ST00830SE (http://

[[Page 70013]]

rgl.faa.gov/Regulatory_and_Guidance_Library/rgSTC.nsf/0/
38B606833BBD98B386257FAA00602538?OpenDocument&Highlight=st00830se) 
does not affect the ability to accomplish the actions required by 
this AD. Therefore, for airplanes on which STC ST00830SE is 
installed, a ``change in product'' alternative method of compliance 
(AMOC) approval request is not necessary to comply with the 
requirements of 14 CFR 39.17.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by an evaluation by the design approval 
holder indicating that certain fastener locations in the window 
corner surround structure are subject to widespread fatigue damage. 
We are issuing this AD to detect and correct fatigue cracking around 
certain fastener locations that could cause multiple window corner 
skin cracks, which could result in rapid decompression and 
consequent loss of structural integrity of the airplane.

(f) Compliance

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

(g) Repetitive Inspections and Repair

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1351, dated 
July 8, 2015: Do an external high frequency eddy current (HFEC) 
inspection for cracking of the skin around the fastener locations at 
the upper forward and lower aft corners of each window between 
station (STA) 360 and STA 540, as applicable, and at the lower 
forward and upper aft corners of each window between STA 727 and STA 
887, in accordance with the Accomplishment Instructions of Boeing 
Alert Service Bulletin 737-53A1351, dated July 8, 2015. Repeat the 
inspection thereafter at the applicable times specified in paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 737-53A1351, 
dated July 8, 2015. If any crack is found during any inspection, 
repair before further flight using a method approved in accordance 
with the procedures specified in paragraph (i) of this AD.

(h) Exception to the Service Bulletin Specifications

    Although Boeing Alert Service Bulletin 737-53A1351, dated July 
8, 2015, specifies to contact Boeing for repair instructions, and 
specifies that action as ``RC'' (Required for Compliance), this AD 
requires repair before further flight using a method approved in 
accordance with the procedures specified in paragraph (i) of this 
AD.

(i) 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 (j) 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, modification, or alteration 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. To be approved, the 
repair method, modification deviation, or alteration deviation must 
meet the certification basis of the airplane and the approval must 
specifically refer to this AD.
    (4) Except as required by paragraph (h) of this AD: For service 
information that contains steps that are labeled as RC, the 
provisions of paragraphs (i)(4)(i) and (i)(4)(ii) of this AD apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, must be done to comply 
with the AD. If a step or substep is labeled ``RC Exempt,'' then the 
RC requirement is removed from that step or substep. An AMOC is 
required for any deviations to RC steps, including substeps and 
identified figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance or inspection 
program without obtaining approval of an AMOC, provided the RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(j) Related Information

    For more information about this AD, contact Gaetano Settineri, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6577; 
fax: 425-917-6590; email: gaetano.settineri@faa.gov.

(k) 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 737-53A1351, dated July 8, 
2015.
    (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 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 September 28, 2016.
Dionne Palermo,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-24197 Filed 10-7-16; 8:45 am]
 BILLING CODE 4910-13-P
```