[Federal Register Volume 83, Number 94 (Tuesday, May 15, 2018)]
[Proposed Rules]
[Pages 22417-22420]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-10209]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0408; Product Identifier 2017-NM-146-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede Airworthiness Directive (AD) 2016-13-
16, which applies to all The Boeing Company Model 737-600, -700, -700C, 
-800, -900, and -900ER series airplanes. AD 2016-13-16 requires 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. Since we issued AD 2016-13-16, we have determined 
that clarification of inspection areas and serial number information of 
the horizontal stabilizer is necessary. Therefore, this proposed AD 
would retain the requirements of AD 2016-13-16, with revised service 
information that clarifies the inspection areas and serial number 
information of the horizontal stabilizer. We are proposing this AD to 
address the unsafe condition on these products.

DATES: We must receive comments on this proposed AD by June 29, 2018.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     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 NPRM, 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 the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this NPRM, 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: 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:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2018-0408; 
Product Identifier 2017-NM-146-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this NPRM. We will consider all 
comments received by the closing date and may amend this NPRM 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.

[[Page 22418]]

Discussion

    We issued AD 2016-13-16, Amendment 39-18581 (81 FR 44503, July 8, 
2016) (``AD 2016-13-16''), for all The Boeing Company Model 737-600, -
700, -700C, -800, -900, and -900ER series airplanes. AD 2016-13-16 
requires an identification plate 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. AD 2016-13-16 
resulted from 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 issued AD 2016-13-16 to address cracking of the rear spar 
upper chord, which can result in the failure of the upper chord, 
consequent departure of the horizontal stabilizer from the airplane, 
and loss of control of the airplane.

Actions Since AD 2016-13-16 Was Issued

    Since we issued AD 2016-13-16, it has been determined that 
clarification of inspection areas and serial number information of the 
horizontal stabilizer is necessary. Therefore, the service information 
has been revised to clarify the inspection areas for cracking and 
serial number information of the horizontal stabilizer.

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.

FAA's Determination

    We are proposing this AD 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.

Proposed AD Requirements

    Although this proposed AD does not explicitly restate the 
requirements of AD 2016-13-16, this proposed AD would retain all 
requirements of AD 2016-13-16. Those requirements are referenced in the 
service information identified previously, which, in turn, is 
referenced in paragraph (g) of this proposed AD. This proposed AD would 
clarify the inspection areas and serial number information of the 
horizontal stabilizer. This proposed AD would also require 
accomplishment of the actions identified as ``RC'' (required for 
compliance) in the Accomplishment Instructions of Boeing Alert Service 
Bulletin 737-55A1097, Revision 1, dated September 20, 2017, described 
previously.
    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-2018-0408.

Costs of Compliance

    We estimate that this proposed AD affects 1,748 airplanes of U.S. 
registry. We estimate the following costs to comply with this proposed 
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 the      hour = $85.
 horizontal stabilizer.
HFEC inspection.......................  6 work-hour x $85 per                  0             510         891,480
                                         hour = $510.
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    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this proposed 
AD.
    According to the manufacturer, all of the costs of this proposed 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 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 have 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 that the proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,

[[Page 22419]]

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

The Boeing Company: Docket No. FAA-2018-0408; Product Identifier 
2017-NM-146-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by June 29, 
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

    This AD applies to all The Boeing Company Model 737-600, -700, -
700C, -800, -900, and 900ER series airplanes, certificated in any 
category.

(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, 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 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) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd.,

[[Page 22420]]

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.

    Issued in Des Moines, Washington, on May 7, 2018.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2018-10209 Filed 5-14-18; 8:45 am]
 BILLING CODE 4910-13-P


