83 FR 56699 - Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 83, Issue 220 (November 14, 2018)

We are superseding Airworthiness Directive (AD) 2016-13-16, which applied to all The Boeing Company Model 737-600, -700, -700C, - 800, -900, and -900ER series airplanes. AD 2016-13-16 required an inspection or records check to determine if affected horizontal stabilizers are installed, related investigative actions, and, for affected horizontal stabilizers, repetitive inspections for any crack of the horizontal stabilizer rear spar upper chord, and corrective action if necessary. This AD requires retaining the requirements of AD 2016-13-16, with revised service information that clarifies the inspection areas and serial number information of the horizontal stabilizer. This AD was prompted by reports of a manufacturing oversight, in which a supplier omitted the required protective finish on certain bushings installed in the rear spar upper chord on horizontal stabilizers, which could lead to galvanic corrosion and consequent cracking of the rear spar upper chord. We are issuing this AD to address the unsafe condition on these products.

[Federal Register Volume 83, Number 220 (Wednesday, November 14, 2018)]
[Rules and Regulations]
[Pages 56699-56702]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-24684]



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Rules and Regulations
                                                Federal Register
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This section of the FEDERAL REGISTER contains regulatory documents 
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Federal Register / Vol. 83, No. 220 / Wednesday, November 14, 2018 / 
Rules and Regulations

[[Page 56699]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0408; Product Identifier 2017-NM-146-AD; Amendment 
39-19495; AD 2018-23-09]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: We are superseding Airworthiness Directive (AD) 2016-13-16, 
which applied to all The Boeing Company Model 737-600, -700, -700C, -
800, -900, and -900ER series airplanes. AD 2016-13-16 required an 
inspection or records check to determine if affected horizontal 
stabilizers are installed, related investigative actions, and, for 
affected horizontal stabilizers, repetitive inspections for any crack 
of the horizontal stabilizer rear spar upper chord, and corrective 
action if necessary. This AD requires retaining the requirements of AD 
2016-13-16, with revised service information that clarifies the 
inspection areas and serial number information of the horizontal 
stabilizer. This AD was prompted by reports of a manufacturing 
oversight, in which a supplier omitted the required protective finish 
on certain bushings installed in the rear spar upper chord on 
horizontal stabilizers, which could lead to galvanic corrosion and 
consequent cracking of the rear spar upper chord. We are issuing this 
AD to address the unsafe condition on these products.

DATES: This AD is effective December 19, 2018.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of December 19, 
2018.

ADDRESSES: For service information identified in this final rule, 
contact Boeing Commercial Airplanes, Attention: Contractual & Data 
Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 
90740-5600; telephone 562-797-1717; internet https://www.myboeingfleet.com. You may view this service information at the 
FAA, Transport Standards Branch, 2200 South 216th St., Des Moines, WA. 
For information on the availability of this material at the FAA, call 
206-231-3195. It is also available on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-
0408.

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-2018-
0408; or in person at Docket Operations between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays. The AD docket contains 
this final rule, the regulatory evaluation, any comments received, and 
other information. The address for Docket Operations (phone: 800-647-
5527) is 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: Lu Lu, Aerospace Engineer, Airframe 
Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 
98198; phone and fax: 206-231-3525; email: [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to supersede AD 2016-13-16, Amendment 39-18581 (81 FR 44503, 
July 8, 2016) (``AD 2016-13-16''). AD 2016-13-16 applied to all The 
Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER 
series airplanes. The NPRM published in the Federal Register on May 15, 
2018 (83 FR 22417). The NPRM was prompted by a determination that 
clarification of inspection areas and serial number information of the 
horizontal stabilizer is necessary and reports of a manufacturing 
oversight, in which a supplier omitted the required protective finish 
on certain bushings installed in the rear spar upper chord on 
horizontal stabilizers, which could lead to galvanic corrosion and 
consequent cracking of the rear spar upper chord. The NPRM proposed to 
continue to require an inspection or records check to determine if 
affected horizontal stabilizers are installed, related investigative 
actions, and, for affected horizontal stabilizers, repetitive 
inspections for any crack of the horizontal stabilizer rear spar upper 
chord, and corrective action if necessary. The NPRM also proposed to 
clarify the inspection areas and serial number information of the 
horizontal stabilizer. We are issuing this AD to address cracking of 
the rear spar upper chord, which could result in the failure of the 
upper chord, consequent departure of the horizontal stabilizer from the 
airplane, and loss of control 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. Air Line Pilots Association, 
International (ALPA), Boeing, and United Airlines stated that they 
supported 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 the actions specified 
in the NPRM.
    We concur with the commenter. We have redesignated paragraph (c) of 
the proposed AD as paragraph (c)(1) of this AD and added 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 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.

Request To Review Parts Installation Limitations Paragraph

    Southwest Airlines (SWA) requested that we review the ``Parts 
Installation Limitation'' paragraph in the proposed AD. SWA stated that 
Boeing Alert Service Bulletin 737-55A1097, Revision

[[Page 56700]]

1, dated September 20, 2017, specifies that an operator can either do a 
check of delivery and maintenance records to find the serial number of 
the horizontal stabilizer installed on the airplane during production 
and to determine if the horizontal stabilizer has been exchanged, or an 
operator can gain access to the horizontal stabilizer identification 
plate and do an inspection of the identification plate to find the 
serial numbers of the horizontal stabilizers.
    SWA stated that it does not agree with the use of maintenance 
records to validate serial numbers based on the potential error of not 
recording the full serial number (manufacturer code and serial number) 
from the identification plate within the maintenance record 
documentation. SWA commented that it has determined that the delivery 
record and physical verification are correct methods in confirming that 
the serial numbers are installed.
    We partially agree with the commenter's request. We have reviewed 
the effectiveness of performing a records check. We disagree with the 
commenter that a records check is not a valid method and note that it 
is acceptable for complying with certain actions required by paragraph 
(g) of this AD. As specified in Note 17 of paragraph 3.A., ``General 
Information'' of the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-55A1097, Revision 1, dated September 20, 2017, ``A 
check of the airplane maintenance and delivery records is an acceptable 
method to determine if the left and right horizontal stabilizers are 
affected provided the installed components can be conclusively 
determined from that check.'' We agree that if an operator is not 
confident that it cannot positively identify the affected stabilizers 
by using maintenance records, then this method should not be used. In 
addition, Boeing Alert Service Bulletin 737-55A1097, Revision 1, dated 
September 20, 2017, specifies a check of delivery and maintenance 
records with a table for the affected manufacturer code and serial 
number combination to ensure all the affected parts are captured.
    In regards to the ``Parts Installation Limitation'' paragraph in 
this AD, there is no option to do a check of the airplane maintenance 
and delivery records. As specified in paragraph (i)(1) of this AD, a 
horizontal stabilizer may be installed if the part is inspected in 
accordance with ``Part 2: Horizontal Stabilizer Identification Plate 
Inspection'' of the Accomplishments Instructions of Boeing Alert 
Service Bulletin 737-55A1097, Revision 1, dated September 20, 2017, and 
no affected serial number is found. As specified in paragraph (i)(2) of 
this AD, a horizontal stabilizer may be installed if the part is 
inspected in accordance with ``Part 2: Horizontal Stabilizer 
Identification Plate Inspection'' of the Accomplishments Instructions 
of Boeing Alert Service Bulletin 737-55A1097, Revision 1, dated 
September 20, 2017, and an affected serial number is found, provided 
the actions specified in paragraphs (i)(2)(i) and (i)(2)(ii) of this AD 
are done, as applicable. We have not changed this AD 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 change 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 addressing 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 737-55A1097, Revision 1, 
dated September 20, 2017. This service information describes procedures 
for an identification plate inspection or records check to determine 
whether affected horizontal stabilizers are installed, related 
investigative actions, and for affected horizontal stabilizers, 
repetitive high frequency eddy current (HFEC) inspections for any crack 
of the horizontal stabilizer rear spar upper chord, and corrective 
action. 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 1,748 airplanes of U.S. registry. 
We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                Cost per         Cost on U.S.
              Action                      Labor cost           Parts cost        product          operators
----------------------------------------------------------------------------------------------------------------
Inspection or records check to     1 work-hour x $85 per                 $0             $85  $148,580.
 determine the serial number of     hour = $85.
 the horizontal stabilizer.
HFEC inspection (horizontal        6 work-hour x $85 per                  0             510  Up to $891,480.
 stabilizer with affected serial    hour = 510.
 number).
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this AD.
    According to the manufacturer, all of the costs of this AD may be 
covered under warranty, thereby reducing the cost impact on affected 
individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all available costs in our 
cost estimate.

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

[[Page 56701]]

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 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 and 
associated appliances to the Director of the System Oversight Division.

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),
    (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 removing Airworthiness Directive (AD) 
2016-13-16, Amendment 39-18581 (81 FR 44503, July 8, 2016), and adding 
the following new AD:

2018-23-09 The Boeing Company: Amendment 39-19495; Docket No. FAA-
2018-0408; Product Identifier 2017-NM-146-AD.

(a) Effective Date

    This AD is effective December 19, 2018.

(b) Affected ADs

    This AD replaces AD 2016-13-16, Amendment 39-18581 (81 FR 44503, 
July 8, 2016) (``AD 2016-13-16'').

(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 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 55, Stabilizers.

(e) Unsafe Condition

    This AD was prompted by reports of a manufacturing oversight, in 
which a supplier omitted the required protective finish on certain 
bushings installed in the rear spar upper chord on horizontal 
stabilizers, which could lead to galvanic corrosion and consequent 
cracking of the rear spar upper chord. We are issuing this AD to 
address cracking of the rear spar upper chord, which could result in 
the failure of the upper chord, consequent departure of the 
horizontal stabilizer from the airplane, and loss of control of the 
airplane.

(f) Compliance

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

(g) Required Actions

    Except as required by paragraph (h) of this AD: At the 
applicable times specified in paragraph 1.E., ``Compliance,'' of 
Boeing Alert Service Bulletin 737-55A1097, Revision 1, dated 
September 20, 2017, do all applicable actions identified as ``RC'' 
(required for compliance) in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
55A1097, Revision 1, dated September 20, 2017.

(h) Exceptions to Service Information

    (1) For purposes of determining compliance with the requirements 
of this AD: Where Boeing Alert Service Bulletin 737-55A1097, 
Revision 1, dated September 20, 2017, uses the phrase ``the Revision 
1 date of this service bulletin,'' this AD requires using ``the 
effective date of this AD.''
    (2) Where Boeing Alert Service Bulletin 737-55A1097, Revision 1, 
dated September 20, 2017, specifies contacting Boeing, and specifies 
that action as RC: This AD requires repair using a method approved 
in accordance with the procedures specified in paragraph (k) of this 
AD.

(i) Parts Installation Limitations

    As of the effective date of this AD, no person may install a 
horizontal stabilizer on any airplane, except as specified in 
paragraphs (i)(1) or (i)(2) of this AD.
    (1) A horizontal stabilizer may be installed if the part is 
inspected in accordance with ``Part 2: Horizontal Stabilizer 
Identification Plate Inspection'' of the Accomplishments 
Instructions of Boeing Alert Service Bulletin 737-55A1097, Revision 
1, dated September 20, 2017, and no affected serial number is found.
    (2) A horizontal stabilizer may be installed if the part is 
inspected in accordance with ``Part 2: Horizontal Stabilizer 
Identification Plate Inspection'' of the Accomplishments 
Instructions of Boeing Alert Service Bulletin 737-55A1097, Revision 
1, dated September 20, 2017, and an affected serial number is found, 
provided that the actions specified in paragraphs (i)(2)(i) and 
(i)(2)(ii) of this AD are done, as applicable.
    (i) Initial and repetitive high frequency eddy current (HFEC) 
inspections, which are part of the required actions specified in 
paragraph (g) of this AD, are completed within the compliance times 
specified in paragraph (g) of this AD.
    (ii) All applicable corrective actions, which are part of the 
required actions specified in paragraph (g) of this AD, are done 
within the compliance times specified in paragraph (g) of this AD.

(j) Credit for Previous Actions

    For Groups 1 and 2, Configuration 1 airplanes, as identified in 
Boeing Alert Service Bulletin 737-55A1097, Revision 1, dated 
September 20, 2017: This paragraph provides credit for the actions 
specified in paragraph (g) of this AD, if those actions were 
performed before the effective date of this AD using Boeing Alert 
Service Bulletin 737-55A1097, dated July 1, 2015.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle 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 (l)(1) of this AD. Information may be 
emailed to: [email protected].
    (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 Branch, FAA, to make those findings. To be

[[Page 56702]]

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 2016-13-16 are approved as 
AMOCs for the corresponding provisions of Boeing Alert Service 
Bulletin 737-55A1097, Revision 1, dated September 20, 2017, that are 
required by paragraph (g) of this AD.
    (5) Except as required by paragraph (h)(2) of this AD: For 
service information that contains steps that are labeled as Required 
for Compliance (RC), the provisions of paragraphs (k)(5)(i) and 
(k)(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 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.

(l) Related Information

    (1) For more information about this AD, contact Lu Lu, Aerospace 
Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 South 
216th St., Des Moines, WA 98198; phone and fax: 206-231-3525; email: 
[email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (m)(3) and (m)(4) of this AD.

(m) 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 737-55A1097, Revision 1, dated 
September 20, 2017.
    (ii) [Reserved]
    (3) 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-
5600; telephone 562-797-1717; internet https://www.myboeingfleet.com.
    (4) You may view this service information at the FAA, Transport 
Standards Branch, 2200 South 216th St., Des Moines, WA. For 
information on the availability of this material at the FAA, call 
206-231-3195.
    (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 Des Moines, Washington, on November 2, 2018.
Jeffrey E. Duven,
Director, System Oversight Division, Aircraft Certification Service.
[FR Doc. 2018-24684 Filed 11-13-18; 8:45 am]
 BILLING CODE 4910-13-P