
[Federal Register Volume 84, Number 36 (Friday, February 22, 2019)]
[Rules and Regulations]
[Pages 5589-5592]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-02930]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0409; Product Identifier 2017-NM-120-AD; Amendment 
39-19559; AD 2019-03-07]
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 superseding Airworthiness Directive (AD) 2017-16-05, 
which applied to certain The Boeing Company Model 737-600, -700, -700C, 
-800, -900, and -900ER series airplanes. AD 2017-16-05 required a one-
time detailed visual inspection for discrepancies in the Krueger flap 
bullnose attachment hardware, and related investigative and corrective 
actions if necessary. This AD adds airplanes and an additional 
inspection to determine if any Krueger flap no. 1, 2, 3, or 4 has been 
replaced, and related investigative and corrective actions. Since this 
is a rotable parts issue, the applicability of this AD has been 
expanded beyond the airplanes listed in the related service bulletin to 
include all airplanes on which a Krueger flap bullnose may be 
installed. This AD was prompted by a report of a Krueger flap bullnose 
departing an airplane during taxi, which caused damage to the wing 
structure and thrust reverser, and a report of a missing no. 2 Krueger 
flap bullnose hinge bolt from an airplane that was not included in the 
effectivity of AD 2017-16-05. We are issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective March 29, 2019.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of March 29, 
2019.

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; phone: 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-
0409.

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-
0409; 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

[[Page 5590]]

Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Alan Pohl, Aerospace Engineer, 
Airframe Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des 
Moines, WA 98198; phone and fax: 206-231-3527; email: 
alan.pohl@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to supersede AD 2017-16-05, Amendment 39-18982 (82 FR39344, 
August 18, 2017) (``AD 2017-16-05''). AD 2017-16-05 applied to certain 
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 FR22420). The NPRM was prompted by a report of a Krueger flap 
bullnose departing an airplane during taxi, which caused damage to the 
wing structure and thrust reverser, and a report of a missing no. 2 
Krueger flap bullnose hinge bolt from an airplane that was not included 
in the effectivity of AD 2017-16-05. The NPRM proposed to continue to 
require a one-time detailed visual inspection for discrepancies in the 
Krueger flap bullnose attachment hardware, and related investigative 
and corrective actions, if necessary. The NPRM also proposed to add 
airplanes and an additional inspection to determine if any Krueger flap 
no. 1, 2, 3, or 4 has been replaced, and related investigative and 
corrective actions. Since this is a rotable parts issue, the 
applicability of this AD has been expanded beyond the airplanes listed 
in the related service bulletin to include all airplanes on which a 
Krueger flap bullnose may be installed. We are issuing this AD to 
address missing Krueger flap bullnose hardware. Such missing hardware 
could result in the Krueger flap bullnose departing the airplane during 
flight, which could damage empennage structure and lead to the 
inability to maintain continued safe flight and landing.

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 concurred with the content of the NPRM. Delta Air Lines 
(DAL) and American Airlines (AAL) concurred with the intent of the 
NPRM.

Effect of Winglets on Accomplishment of the Proposed Actions

    Aviation Partners Boeing stated that accomplishing the Supplemental 
Type Certificate (STC) ST00830SE does not affect 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 Remove Airplanes From the Applicability

    All Nippon Airways (ANA) requested that we remove the airplanes 
identified in paragraph (c)(3) of the proposed AD. ANA stated that 
those airplanes are not required to do the actions specified in 
paragraph (g) of the proposed AD.
    We disagree with the request. Although the airplanes identified in 
paragraph (c)(1)(iii) of this AD (paragraph (c)(3) of the proposed AD) 
are not required to do the actions specified in paragraph (g) of this 
AD, those airplanes must still comply with the parts installation 
limitation specified in paragraph (i) of this AD. We have not changed 
this AD in this regard.

Request for a Different Method of Compliance

    DAL requested that we include an option in paragraph (i) of the 
proposed AD to install the Krueger flap before accomplishing the 
required actions. DAL mentioned that it has updated its manuals to 
inspect after installation on the airplane, not prior to installation.
    We agree that clarification is necessary. The required inspection 
of the Krueger flap bullnose can only be accomplished after 
installation on the Krueger flap assembly, either prior to or after 
installation on the airplane. We have revised paragraph (i) to specify 
that the actions required by paragraph (g) of this AD must be 
accomplished after installation but prior to further flight.

Request To Clarify Which Krueger Flaps Are Affected

    DAL and AAL requested that we clarify paragraph (i) of the proposed 
AD to specify affected Krueger flap(s) and Krueger flap bullnose(s). 
DAL stated that not all four positions need to be inspected, only the 
Krueger flap(s) and Krueger flap bullnose(s) being installed. AAL 
suggested that we reword paragraph (i) of the proposed AD to improve 
clarity.
    We agree with the request because it is not necessary to perform 
the actions specified in paragraph (i) of this AD on all four Krueger 
flap(s) or Krueger flap bullnose(s). Only the Krueger flap(s) or 
Krueger flap bullnose(s) being installed must be inspected. We have 
revised paragraph (i) of this AD to specify: ``These actions are 
required only for the Krueger flap(s) or Krueger flap bullnose(s) being 
installed.''

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 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 737-57A1327, Revision 2, 
dated July 25, 2017. This service information describes procedures for 
a one-time detailed visual inspection for discrepancies in the Krueger 
flap bullnose attachment hardware, and related investigative and 
corrective actions; and an inspection to determine if any Krueger flap 
no. 1, 2, 3, or 4 has been replaced, 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.

Costs of Compliance

    We estimate that this AD affects 1,814 airplanes of U.S. registry. 
We estimate the following costs to comply with this AD:

[[Page 5591]]



                                                 Estimated Costs
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                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Inspection of the Krueger flap          3 work-hours x $85 per                $0            $255        $381,225
 bullnose hardware (1,495 airplanes)     hour = $255.
 (retained actions from AD 2017-16-05).
Inspection to determine if any Krueger  3 work-hours x $85 per                 0             255         462,570
 flap no. 1, 2, 3, or 4 has been         hour = $255.
 replaced (1,814 airplanes) (new
 action).
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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 AD.
    According to the manufacturer, some 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 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) 
2017-16-05, Amendment 39-18982 (82 FR 39344, August 18, 2017), and 
adding the following new AD:

2019-03-07 The Boeing Company: Amendment 39-19559; Docket No. FAA-
2018-0409; Product Identifier 2017-NM-120-AD.

(a) Effective Date

    This AD is effective March 29, 2019.

(b) Affected ADs

    This AD replaces AD 2017-16-05, Amendment 39-18982 (82 FR 39344, 
August 18, 2017) (``AD 2017-16-05'').

(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, as specified in paragraphs (c)(1)(i) through 
(c)(1)(iii) of this AD.
    (i) Airplanes in Groups 1 and 2 as identified in Boeing Alert 
Service Bulletin 737-57A1327, Revision 2, dated July 25, 2017 
(``BASB 737-57A1327, R2'').
    (ii) Airplanes in Group 3, as identified in BASB 737-57A1327, 
R2, except where this service bulletin specifies the groups as line 
numbers 6422 through 6465 inclusive, this AD specifies those groups 
as line number 6422 through any line number airplane with an 
original Certificate of Airworthiness or an original Export 
Certificate of Airworthiness dated on or before the effective date 
of this AD.
    (iii) All Model 737-600, -700, -700C, -800, -900 and -900ER 
series airplanes with an original Certificate of Airworthiness or an 
original Export Certificate of Airworthiness dated after the 
effective date of this AD.
    (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 57, Wings.

(e) Unsafe Condition

    This AD was prompted by a report of a Krueger flap bullnose 
departing an airplane during taxi, which caused damage to the wing 
structure and thrust reverser, and a report of a missing no. 2 
Krueger flap bullnose hinge bolt from an airplane that was not 
included in the effectivity of AD 2017-16-05. We are issuing this AD 
to address missing Krueger flap bullnose hardware. Such missing 
hardware could result in the Krueger flap bullnose departing the 
airplane during flight, which could damage empennage structure and 
lead to the inability to maintain continued safe flight and landing.

(f) Compliance

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

(g) Required Actions

    For airplanes identified in paragraphs (c)(1)(i) and (c)(1)(ii) 
of this AD: Except as required by paragraph (h) of this AD, at the 
applicable times specified in paragraph 1.E., ``Compliance,'' of 
BASB 737-57A1327, R2, do all applicable actions identified as ``RC''

[[Page 5592]]

(required for compliance) in, and in accordance with, the 
Accomplishment Instructions of BASB 737-57A1327, R2.

(h) Exceptions to Service Information Specifications

    (1) For purposes of determining compliance with the requirements 
of this AD: Where BASB 737-57A1327, R2 uses the phrase ``the 
original issue date of this service bulletin,'' this AD requires 
using September 22, 2017 (the effective date of AD 2017-16-05).
    (2) For purposes of determining compliance with the requirements 
of this AD: Where BASB 737-57A1327, R2 uses the phrase ``the 
Revision 2 date of this service bulletin,'' this AD requires using 
``the effective date of this AD.''

(i) Parts Installation Limitation

    As of the effective date of this AD, no person may install a 
Krueger flap or Krueger flap bullnose on any airplane identified in 
paragraph (c)(1)(i), (c)(1)(ii), or (c)(1)(iii) of this AD, unless 
the actions required by paragraph (g) of this AD have been 
accomplished on the Krueger flap bullnose after installation but 
prior to further flight. These actions are required only for the 
Krueger flap(s) or Krueger flap bullnose(s) being installed.

(j) Credit for Previous Actions

    (1) This paragraph provides credit for the actions specified in 
paragraph (g) of this AD, if those actions were performed before 
September 22, 2017 (the effective date of AD 2017-16-05), using 
Boeing Alert Service Bulletin 737-57A1327, dated May 20, 2016.
    (2) 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-
57A1327, Revision 1, dated September 28, 2016.

(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: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration required by this AD 
if it is approved by the Boeing Commercial Airplanes Organization 
Designation Authorization (ODA) that has been authorized by the 
Manager, Seattle ACO Branch, FAA, 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 2017-16-05 are approved as 
AMOCs for the corresponding provisions of BASB 737-57A1327, R2 that 
are required by paragraph (g) of this AD.
    (5) For service information that contains steps that are labeled 
as 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) Operators may deviate from steps not labeled as RC by 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 Alan Pohl, 
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3527; 
email: alan.pohl@faa.gov.
    (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 737-57A1327, Revision 2, dated 
July 25, 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; phone: 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 February 7, 2019.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2019-02930 Filed 2-21-19; 8:45 am]
BILLING CODE 4910-13-P


