
[Federal Register Volume 82, Number 33 (Tuesday, February 21, 2017)]
[Rules and Regulations]
[Pages 11132-11134]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-01825]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-6426; Directorate Identifier 2016-NM-023-AD; 
Amendment 39-18791; AD 2017-02-12]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all The 
Boeing Company Model 737-300, -400, and -500 series airplanes. This AD 
was prompted by reports of intergranular cracks on the front spar chord 
lugs of the outboard horizontal stabilizer. This AD requires repetitive 
inspections of the front spar chord lugs and lug bores of the 
horizontal stabilizer, and repair if necessary. We are issuing this AD 
to address the unsafe condition on these products.

DATES: This AD is effective March 28, 2017.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of March 28, 
2017.

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-
6426.

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-
6426; 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: Payman Soltani, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office (ACO), 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 
562-627-5313; fax: 562-627-5210; email: Payman.Soltani@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 737-300, -400, and -500 series airplanes. The NPRM published in 
the Federal Register on May 10, 2016 (81 FR 28774) (``the NPRM''). The 
NPRM was prompted by reports of intergranular cracks on the front spar 
chord lugs of the outboard horizontal stabilizer. The NPRM proposed to 
require repetitive inspections of the front spar chord lugs and lug 
bores of the horizontal stabilizer, and repair if necessary. We are 
issuing this AD to detect and correct cracking of the front spar chord 
lugs of the horizontal stabilizer. Such cracking could cause stabilizer 
instability, adversely affect controllability of the airplane, and 
adversely affect the 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 had no objection to the NPRM.

Effect of Winglets on Accomplishment of the Proposed Actions

    Aviation Partners Boeing stated that accomplishing Supplemental 
Type

[[Page 11133]]

Certificate (STC) ST01219SE does not affect the ability to accomplish 
the actions specified in the proposed AD.
    We concur with the commenter. We have redesignated paragraph (c) of 
the proposed AD as paragraph (c)(1) and added paragraph (c)(2) to this 
AD to state that installation of 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 Revise Compliance Time

    All Nippon Airways (ANA) requested that we revise paragraph (i) of 
the proposed AD to provide a grace period of 27 months after the 
effective date of the AD in which to accomplish the initial inspection 
on horizontal stabilizers, including replacement horizontal 
stabilizers. ANA stated that these revisions would reduce the burden on 
operators. ANA proposed new, complex language for paragraph (i) of the 
proposed AD that would incorporate their proposal.
    We partially agree. We agree that the 27-month after the effective 
date of this AD grace period applies to replacement horizontal 
stabilizers. However, we do not agree to add a grace period of 27 
months to paragraph (i) of this AD or to incorporate ANA's proposed 
language. We have revised paragraph (i) of this AD to clarify the 
provisions to address ANA's concern and to align more closely with the 
language used in similar ADs.
    The compliance time in paragraph (g) of this AD applies to all 
horizontal stabilizers, including those installed after the effective 
date of this AD. Because the unsafe condition is related to corrosion, 
the compliance times in this AD are measured in months. Therefore, time 
accumulated on a horizontal stabilizer on and off an airplane applies 
to the initial compliance time and the repetitive inspection interval. 
A horizontal stabilizer that is off the airplane when the next 
inspection is due is not required to be inspected until it is ready to 
be installed on the airplane.

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 737-55A1092, dated August 
7, 2015. The service information describes procedures for inspections 
for corrosion and cracking of the front spar chord lugs of the 
horizontal stabilizer, and inspections for corrosion of the lug bores. 
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 346 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
----------------------------------------------------------------------------------------------------------------
Inspections..............  14 work-hours x $85 per                $0   $1,190 per            $411,740 per
                            hour = $1,190 per                           inspection cycle.     inspection cycle
                            inspection cycle.
----------------------------------------------------------------------------------------------------------------

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

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701: ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    This AD will not have federalism implications under Executive Order 
13132. This AD will not have a substantial direct effect on the States, 
on the relationship between the national government and the States, or 
on the distribution of power and responsibilities among the various 
levels of government.
    For the reasons discussed above, I certify that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    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):


[[Page 11134]]


2017-02-12 The Boeing Company: Amendment 39-18791; Docket No. FAA-
2016-6426; Directorate Identifier 2016-NM-023-AD.

(a) Effective Date

    This AD is effective March 28, 2017.

(b) Affected ADs

    None.

(c) Applicability

    (1) This AD applies to all The Boeing Company Model 737-300, -
400, and -500 series airplanes, certificated in any category.
    (2) Installation of Supplemental Type Certificate (STC) 
ST01219SE (http://rgl.faa.gov/Regulatory_and_Guidance_Library/
rgstc.nsf/0/ebd1cec7b301293e86257cb30045557a/$FILE/ST01219SE.pdf) 
does not affect the ability to accomplish the actions required by 
this AD. Therefore, for airplanes on which STC ST01219SE is 
installed, a ``change in product'' alternative method of compliance 
(AMOC) approval request is not necessary to comply with the 
requirements of 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 intergranular cracks on the 
front spar chord lugs of the outboard horizontal stabilizer. We are 
issuing this AD to detect and correct cracking of the front spar 
chord lugs of the horizontal stabilizer. Such cracking could cause 
stabilizer instability, adversely affect controllability of the 
airplane, and adversely affect the structural integrity of the 
airplane.

(f) Compliance

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

(g) Repetitive Inspections and Repairs

    Within 27 months after the effective date of this AD: Do the 
actions required by paragraphs (g)(1) and (g)(2) of this AD, and do 
all applicable repairs, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 737-55A1092, dated 
August 7, 2015, except as required by paragraph (h) of this AD. Do 
all applicable repairs before further flight. Repeat the inspections 
specified in paragraphs (g)(1) and (g)(2) of this AD thereafter at 
the applicable intervals specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-55A1092, dated 
August 7, 2015.
    (1) Do a detailed inspection for corrosion and an ultrasonic 
inspection for cracking of the front spar chord lugs of the left and 
right horizontal stabilizers.
    (2) Do a detailed inspection for corrosion of the lug bores of 
the front spar chord of the left and right horizontal stabilizers.

(h) Service Information Exception

    Where Boeing Alert Service Bulletin 737-55A1092, dated August 7, 
2015, specifies to contact Boeing for appropriate action, and 
specifies that action as ``RC'' (Required for Compliance): Before 
further flight, repair using a method approved in accordance with 
the procedures specified in paragraph (j) of this AD.

(i) Parts Installation Limitation

    As of the effective date of this AD: A horizontal stabilizer may 
be installed on any airplane, provided all applicable actions 
required by the introductory text of paragraph (g) and paragraphs 
(g)(1) and (g)(2) of this AD are done within the compliance times 
specified in the introductory text of paragraph (g) of this AD, and 
in accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-55A1092, dated August 7, 2015, except as 
required by paragraph (h) of this AD.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles Aircraft Certification Office 
(ACO), FAA, has the authority to approve AMOCs for this AD, if 
requested using the procedures found in 14 CFR 39.19. In accordance 
with 14 CFR 39.19, send your request to your principal inspector or 
local Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in paragraph (k) of this AD. 
Information may be emailed to: 9-ANM-LAACO-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, Los Angeles 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 (j)(4)(i) and (j)(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.

(k) Related Information

    For more information about this AD, contact Payman Soltani, 
Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles ACO, 
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5313; fax: 562-627-5210; email: Payman.Soltani@faa.gov.

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Service Bulletin 737-55A1092, dated August 7, 
2015.
    (ii) Reserved.
    (3) For Boeing 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 January 17, 2017.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2017-01825 Filed 2-17-17; 8:45 am]
BILLING CODE 4910-13-P


