Document ID: FAA-2016-9523-0006
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: The Boeing Company Airplanes
Posted Date: 2017-08-11T04:00Z

[Federal Register Volume 82, Number 154 (Friday, August 11, 2017)]
[Proposed Rules]
[Pages 37549-37554]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-16357]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9523; Product Identifier 2016-NM-134-AD]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (SNPRM); reopening 
of comment period.

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SUMMARY: We are revising an earlier notice of proposed rulemaking 
(NPRM) to supersede Airworthiness Directive (AD) 2014-12-13, which 
applies to all The Boeing Company Model 737-100, -200, -200C, -300, -
400, and -500 series airplanes. This action revises the NPRM by 
expanding the inspection area. This action also revises the NPRM by no 
longer proposing to supersede AD 2014-12-13. We are proposing this AD 
to address the unsafe condition on these products. Since these actions 
impose an additional burden over that proposed in the NPRM, we are 
reopening the comment period to allow the public the chance to comment 
on these proposed changes.

DATES: The comment period for the NPRM published in the Federal 
Register on January 5, 2017 (82 FR 1254), is reopened.
    We must receive comments on this SNPRM by September 5, 2017.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:

[[Page 37550]]

     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this SNPRM, contact Boeing 
Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 
2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740; telephone 
562-797-1717; Internet https://www.myboeingfleet.com. You may view this 
referenced service information at the FAA, Transport Standards Branch, 
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-2016-9523.

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-
9523; 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 SNPRM, the regulatory evaluation, any comments received, 
and other information. The street address for the Docket Office (phone: 
800-647-5527) is in the ADDRESSES section. Comments will be available 
in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Payman Soltani, Aerospace Engineer, 
Airframe Section, FAA, Los Angeles Aircraft Certification Office (ACO) 
Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-
627-5313; fax: 562-627-5210; email: payman.soltani@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2016-9523; 
Product Identifier 2016-NM-134-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this SNPRM. We will consider all 
comments received by the closing date and may amend this SNPRM because 
of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    On June 6, 2014, we issued AD 2014-12-13, Amendment 39-17874 (79 FR 
39300, July 10, 2014) (``AD 2014-12-13''). AD 2014-12-13 requires 
actions to address an unsafe condition on all The Boeing Company Model 
737-100, -200, -200C, -300, -400, and -500 series airplanes. AD 2014-
12-13 requires repetitive inspections for cracking of the aft support 
fitting for the main landing gear (MLG) beam, and the rear spar upper 
chord and rear spar web; and repair if necessary.
    We issued an NPRM to amend 14 CFR part 39 by adding an AD to 
supersede AD 2014-12-13 that would apply to all The Boeing Company 
Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. The 
NPRM published in the Federal Register on January 5, 2017 (82 FR 1254) 
(``the NPRM''). The NPRM was prompted by reports of additional cracking 
in the inspar upper skin at Wing Buttock Line (WBL) 157 and in the skin 
at two holes common to the rear spar in the same area, and by reports 
of rear spar web cracks on both wings. Subsequent inspections revealed 
that the right rear spar upper chord was almost completely severed and 
the left rear spar upper chord was completely severed. The NPRM 
proposed to expand the inspection area and add applicable related 
investigative and corrective actions.

Actions Since NPRM Was Issued

    Since we issued the NPRM, we have determined it is necessary to 
expand the inspection area because the NPRM did not adequately identify 
the inspection area. We have also determined that it is necessary for 
operators to do the inspections in this proposed AD (in the SNPRM) 
before the inspections in AD 2014-12-13 can be terminated. In the NPRM, 
we proposed to supersede AD 2014-12-13 and referred to the compliance 
times in Boeing Alert Service Bulletin 737-57A1318, Revision 1, dated 
July 22, 2016, which would have given operators an additional 4,500 
flight cycles to do the next inspection. However, operators must do the 
inspections at the compliance times required by AD 2014-12-13 until the 
actions required by this proposed AD (in the SNPRM) are done. 
Therefore, we are no longer superseding AD 2014-12-13. However, we have 
included paragraph (k)(2) in this proposed AD (in the SNPRM) to specify 
terminating action for AD 2014-12-13.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 737-57A1318, Revision 1, 
dated July 22, 2016. The service information describes procedures for 
repetitive high frequency eddy current (HFEC) open hole inspections for 
any cracking in the forward support fitting, the aft support fitting, 
the rear spar upper chord, and the rear spar web at the 12 fastener 
holes (locations 1-12). The service information also describes 
procedures for optional HFEC open hole inspections for any cracking in 
the forward support fitting, the aft support fitting, the rear spar 
upper chord, and the rear spar web, and HFEC surface inspections for 
any cracking in the rear spar upper chord and rear spar upper web, as 
applicable. The service information also describes procedures for 
related investigative and corrective actions.
    We also reviewed Boeing Alert Service Bulletin 737-57A1328, dated 
July 22, 2016. The service information describes procedures for 
repetitive eddy current inspections of the left and right wing for any 
cracking in the inspar upper skin and at the repair parts if 
applicable, and related investigative and corrective actions.
    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.

Comments

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

Request To Include Other Inspection Areas

    Boeing requested that the NPRM be revised to include other 
inspection areas during the HFEC open hole inspection. Boeing stated 
that, as written, the NPRM implies that in some options the upper chord 
and web do not need to be inspected during the HFEC open hole 
inspection.
    We agree with the commenter's request for the reasons stated above. 
We have revised the introductory text to paragraph (h) of this proposed 
AD (in the SNPRM) to include an HFEC

[[Page 37551]]

inspection of the forward support fitting, the aft support fitting, the 
rear spar upper chord, and the rear spar web.

Request To Revise the NPRM or Service Information To Allow Installation 
of the Same Type and Size of Fasteners

    All Nippon Airlines (ANA) requested that paragraph (h) of the NPRM 
or the service information be revised to allow installation of the same 
type and size of fasteners previously removed from the airplane after 
the open hole HFEC inspection. ANA stated that for group 7 airplanes, 
figures 25 and 26 of Boeing Alert Service Bulletin 737-57A1318, May 15, 
2013, specify that oversized fasteners are installed at fastener holes 
after the open hole HFEC inspection has been accomplished. ANA stated 
that, however, for the same group 7 airplanes, figures 29 and 30 of 
Boeing Alert Service Bulletin 737-57A1318, Revision 1, dated July 22, 
2016, specify that standard size fasteners are installed at fastener 
holes after the open hole HFEC inspection has been accomplished. ANA 
stated that as a result, operators will have to request alternative 
methods of compliance (AMOCs) for all airplanes on which the actions in 
Boeing Alert Service Bulletin 737-57A1318, May 15, 2013, have already 
been done because paragraph (h) of the NPRM states to do all applicable 
related investigative and corrective actions using Boeing Alert Service 
Bulletin 737-57A1318, Revision 1, dated July 22, 2016, which includes 
the installation of the standard size fasteners. ANA stated that this 
would be a burden for operators, Boeing, and the FAA.
    We agree with the commenter's request to revise this proposed AD. 
Boeing Alert Service Bulletin 737-57A1318, Revision 1, dated July 22, 
2016, should have called out the correct fastener size to be installed 
after the fastener holes have been inspected and oversized as specified 
in Boeing Alert Service Bulletin 737-57A1318, May 15, 2013. Group 7 has 
two configurations: Configuration 1 is for airplanes without a repair; 
Configuration 2 is for airplanes with a repair. We added paragraph 
(h)(2) to this proposed AD (in the SNPRM) to state, ``For group 7, 
configuration 1 airplanes identified in Boeing Alert Service Bulletin 
737-57A1318, Revision 1, dated July 22, 2016: Install the same type and 
same size fasteners as those previously removed from the airplane after 
accomplishing the open hole HFEC inspection specified in the 
introductory text of paragraph (h) of this AD.''

Request for AMOC Approval

    ANA requested that the NPRM be revised to allow approved AMOCs for 
AD 2014-12-13. ANA stated that airplanes have AMOCs for AD 2014-12-23 
for certain repairs done using certain Boeing 737-300/-400/-500 
structural repair manuals or certain Boeing ODA forms. ANA stated that 
existing AMOCs should be considered for AMOC approval in the NPRM.
    We agree with the commenter's request for the reasons provided 
above. We have redesignated paragraph (l)(4) of the proposed AD (in the 
NPRM) as paragraph (l)(5) in this proposed AD (in the SNPRM). We have 
added paragraph (l)(4) to this proposed AD (in the SNPRM) to allow 
AMOCs approved previously for AD 2014-12-13, Amendment 39-17874 (79 FR 
39300, July 10, 2014), as AMOCs for the corresponding provisions of 
paragraphs (g) and (h) of this AD.

Effect of Winglets on Accomplishment of the Proposed Actions

    Aviation Partners Boeing stated that accomplishing the supplemental 
type certificate (STC) ST01219SE does not affect the actions specified 
in the NPRM.
    We concur. We have redesignated paragraph (c) of the proposed AD 
(in the NPRM) as paragraph (c)(1) in this proposed AD and added 
paragraph (c)(2) to this proposed AD to state that ``Installation of 
Supplemental Type Certificate (STC) ST01219SE 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 14 CFR 39.17.''

Request To Clarify the NPRM for Historical Accuracy

    Boeing requested that the NPRM be revised to clarify the content 
for historical accuracy. Boeing stated that in the ``Actions Since AD 
2014-12-13 and 2015-21-08 Were Issued'' paragraph of the preamble of 
the NPRM, the first paragraph described that a 2.375-inch long crack in 
the inspar upper skin was discovered since the issuance of AD 2014-12-
13 and AD 2015-21-08. Boeing stated, however, the discovery of the 
crack led to the issuance of AD 2015-21-08 and not AD 2014-12-13. 
Boeing stated that the AD will become a reference for prior events, and 
therefore, historical accuracy is essential.
    We agree with the commenter to clarify the historical accuracy of 
this SNPRM. While the paragraph, ``Actions Since AD 2014-12-13 and 
2015-21-08 Were Issued,'' is not carried over in the SNPRM, we 
acknowledge that the discovery of a 2.375-inch long crack in the inspar 
upper skin led to the issuance of AD 2015-21-08. We have not changed 
this SNPRM regarding this issue.

FAA's Determination

    We are proposing this SNPRM because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design. 
Certain changes described above expand the scope of the NPRM. As a 
result, we have determined that it is necessary to reopen the comment 
period to provide additional opportunity for the public to comment on 
this SNPRM.

Proposed Requirements of This SNPRM

    This SNPRM would require accomplishing the actions specified in the 
service information described previously, except as discussed under 
``Differences Between this Proposed AD and the Service Information.'' 
For information on the procedures and compliance times, see this 
service information at http://www.regulations.gov by searching for and 
locating Docket No. FAA-2016-9523.
    The phrase ``related investigative actions'' is used in this SNPRM. 
Related investigative actions are follow-on actions that (1) are 
related to the primary action, and (2) further investigate the nature 
of any condition found. Related investigative actions in an AD could 
include, for example, inspections.
    The phrase ``corrective actions'' is used in this SNPRM. Corrective 
actions correct or address any condition found. Corrective actions in 
an AD could include, for example, repairs.

Differences Between This SNPRM and the Service Information

    Boeing Alert Service Bulletin 737-57A1318, Revision 1, dated July 
22, 2016; and Boeing Alert Service Bulletin 737-57A1328, dated July 22, 
2016; specify to contact the manufacturer for certain instructions, but 
this proposed AD would require accomplishment of repair methods, 
modification deviations, and alteration deviations in one of the 
following ways:
     In accordance with a method that we approve; or
     Using data that meet the certification basis of the 
airplane, and that have been approved by the Boeing

[[Page 37552]]

Commercial Airplanes Organization Designation Authorization (ODA) whom 
we have authorized to make those findings.

Costs of Compliance

    We estimate that this AD affects 471 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
----------------------------------------------------------------------------------------------------------------
HFEC open hole inspections......  82 work-hours x $85              $0   $6,970 per           $3,282,870 per
                                   per hour = $6,970                     inspection cycle.    inspection cycle.
                                   per inspection
                                   cycle.
Eddy current inspection.........  14 work-hours x $85              $0   $1,190 per           $560,490 per
                                   per hour = $1,190                     inspection cycle.    inspection cycle.
                                   per inspection
                                   cycle.
----------------------------------------------------------------------------------------------------------------

                                      Estimated Costs for Optional Actions
----------------------------------------------------------------------------------------------------------------
                 Action                          Labor cost             Parts cost         Cost per product
----------------------------------------------------------------------------------------------------------------
Inspection.............................  Up to 41 work-hours x $85               $0   Up to $1,641,435 per
                                          per hour = $3,485 per                        inspection cycle.
                                          inspection cycle.
----------------------------------------------------------------------------------------------------------------

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

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.
    This proposed AD is issued in accordance with authority delegated 
by the Executive Director, Aircraft Certification Service, as 
authorized by FAA Order 8000.51C. In accordance with that order, 
issuance of ADs is normally a function of the Compliance and 
Airworthiness Division, but during this transition period, the 
Executive Director has delegated the authority to issue ADs applicable 
to transport category airplanes to the Director of the System Oversight 
Division.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under the 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.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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):

The Boeing Company: Docket No. FAA-2016-9523; Product Identifier 
2016-NM-134-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by September 5, 
2017.

(b) Affected ADs

    This AD affects AD 2014-12-13, Amendment 39-17874 (79 FR 39300, 
July 10, 2014), and AD 2015-21-08, Amendment 39-18301 (80 FR 65921, 
October 28, 2015).

(c) Applicability

    (1) This AD applies to all The Boeing Company Model 737-100, -
200, -200C, -300, -400, and -500 series airplanes, certificated in 
any category.
    (2) Installation of Supplemental Type Certificate (STC) 
ST01219SE 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 14 CFR 39.17.

(d) Subject

    Air Transport Association (ATA) of America Code 57, Wings.

(e) Unsafe Condition

    This AD was prompted by reports of additional cracking in the 
inspar upper skin at Wing Buttock Line (WBL) 157 and in the skin at 
two holes common to the rear spar in the same area, and rear spar 
web cracks were also noted on both wings. Subsequent inspections 
revealed that the right rear spar upper chord was almost completely 
severed and the left rear spar upper chord was completely severed. 
We are issuing this AD to detect and correct cracking of the forward 
and aft support fittings for the main landing

[[Page 37553]]

gear (MLG) beam, and the rear spar upper chord and rear spar web in 
the area of rear spar station (RSS) 224.14, which could grow and 
result in a fuel leak and possible fire.

(f) Compliance

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

(g) Required Actions for Group 1 Airplanes (MLG Support Fittings and 
Rear Spar)

    For airplanes identified as Group 1 in Boeing Alert Service 
Bulletin 737-57A1318, Revision 1, dated July 22, 2016: At the 
applicable time specified in table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-57A1318, 
Revision 1, dated July 22, 2016, except as required by paragraph 
(j)(3) of this AD, do applicable inspections and corrective actions 
using a method approved in accordance with the procedures specified 
in paragraph (l) of this AD.

(h) Required Actions for Groups 2-7 Airplanes (MLG Support Fittings and 
Rear Spar)

    For airplanes identified as Groups 2-7 in Boeing Alert Service 
Bulletin 737-57A1318, Revision 1, dated July 22, 2016: At the 
applicable time specified in table 2 through table 9 of paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 737-57A1318, 
Revision 1, dated July 22, 2016, except as required by paragraph 
(j)(3) of this AD, do high frequency eddy current (HFEC) open hole 
inspections for any cracking in the forward support fitting, the aft 
support fitting, the rear spar upper chord, and the rear spar web at 
the 12 fastener holes (locations 1-12); or HFEC open hole 
inspections for any cracking in the forward support fitting, the aft 
support fitting, the rear spar upper chord, and the rear spar web, 
and an HFEC surface inspection for any cracking in the rear spar 
upper chord and rear spar upper web; as applicable; and do all 
applicable related investigative and corrective actions; in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-57A1318, Revision 1, dated July 22, 2016, 
except as provided by paragraphs (h)(1) and (h)(2) of this AD, and 
except as required by paragraph (j)(1) of this AD. Do all applicable 
related investigative and corrective actions before further flight. 
Thereafter, repeat the HFEC inspection at the applicable time 
specified in table 2 through table 9 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-57A1318, 
Revision 1, dated July 22, 2016.
    (1) Options provided in Boeing Alert Service Bulletin 737-
57A1318, Revision 1, dated July 22, 2016, for accomplishing the 
inspection are acceptable for the corresponding requirements in the 
introductory text of paragraph (h) of this AD, provided that the 
inspections are done at the applicable times in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-57A1318, 
Revision 1, dated July 22, 2016.
    (2) For Group 7, Configuration 1 airplanes identified in Boeing 
Alert Service Bulletin 737-57A1318, Revision 1, dated July 22, 2016: 
Install the same type and same size fasteners as those previously 
removed from the airplane after accomplishing the open hole HFEC 
inspection specified in the introductory text of paragraph (h) of 
this AD.

(i) Eddy Current Inspection (Inspar Upper Skin)

    For airplanes identified in Boeing Alert Service Bulletin 737-
57A1328, dated July 22, 2016: At the applicable time specified in 
table 1 and table 2 of paragraph 1.E., ``Compliance,'' of Boeing 
Alert Service Bulletin 737-57A1328, dated July 22, 2016, except as 
required by paragraph (j)(2) of this AD, do an eddy current 
inspection of the left and right wings for any cracking in the 
inspar upper skin, and at the repair parts if installed, and do all 
applicable related investigative and corrective actions, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-57A1328, dated July 22, 2016, except as 
required by paragraph (j)(1) of this AD. Do all related 
investigative and corrective actions before further flight. 
Thereafter, repeat the eddy current inspection at the applicable 
time specified in table 1 and table 2 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-57A1328, dated 
July 22, 2016.

(j) Exceptions to the Service Information

    (1) If any cracking is found during any inspection required by 
this AD, and Boeing Alert Service Bulletin 737-57A1318, Revision 1, 
dated July 22, 2016; or Boeing Alert Service Bulletin 737-57A1328, 
dated July 22, 2016; specifies to contact Boeing for appropriate 
action: Before further flight, repair using a method approved in 
accordance with the procedures specified in paragraph (l) of this 
AD.
    (2) Where Boeing Alert Service Bulletin 737-57A1328, dated July 
22, 2016, 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.
    (3) Where Boeing Alert Service Bulletin 737-57A1318, Revision 1, 
dated July 22, 2016, specifies a compliance time ``after the 
Revision 1 date of this service bulletin, whichever occurs later,'' 
this AD requires compliance within the specified compliance time 
after the effective date of this AD.

(k) Terminating Action

    (1) Accomplishing the initial inspections and applicable related 
investigative and corrective actions required by paragraphs (g), 
(h), and (i) of this AD, as applicable, terminates all requirements 
of AD 2015-21-08.
    (2) Accomplishing the initial inspections and applicable related 
investigative and corrective actions required by paragraphs (g) and 
(h) of this AD, as applicable, terminates all requirements of AD 
2014-12-13.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles Aircraft Certification Office (ACO) 
Branch, 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 certification office, 
send it to the attention of the person identified in paragraph 
(m)(1) of this AD. Information may be emailed to: 9-ANM-LAACO-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, Los Angeles ACO Branch, 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) AMOCs approved previously for AD 2014-12-13, Amendment 39-
17874 (79 FR 39300, July 10, 2014), are approved as AMOCs for the 
corresponding provisions of paragraphs (g) and (h) of this AD.
    (5) Except as required by paragraph (j)(1) of this AD: For 
service information that contains steps that are labeled as Required 
for Compliance (RC), the provisions of paragraphs (l)(5)(i) and 
(l)(5)(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 sub-step is labeled ``RC Exempt,'' then 
the RC requirement is removed from that step or sub-step. 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.

(m) Related Information

    (1) For more information about this AD, contact Payman Soltani, 
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5313; fax: 562-627-5210; email: payman.soltani@faa.gov.
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740; 
telephone 562-797-1717; Internet https://www.myboeingfleet.com. You 
may view this referenced service information at the FAA, Transport 
Standards Staff, 1601 Lind Avenue SW., Renton, WA. For information 
on the availability of this material at the FAA, call 425-227-1221.

[[Page 37554]]

    Issued in Renton, Washington, on July 26, 2017.
Jeffrey E. Duven,
Director, System Oversight Division, Aircraft Certification Service.
[FR Doc. 2017-16357 Filed 8-10-17; 8:45 am]
 BILLING CODE 4910-13-P