AD 2017-16-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Boeing | Various | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Missing Krueger flap bullnose 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.
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Required Actions
Perform a one-time detailed visual inspection for discrepancies in the Krueger flap bullnose attachment hardware. Investigate and correct any discrepancies found, if necessary.
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Compliance Time
Before further flight
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Affected Aircraft
The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes.
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Federal Register Abstract
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. 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. This AD requires a one-time detailed visual inspection for discrepancies in the Krueger flap bullnose attachment hardware, and related investigative and corrective actions, if necessary. We are issuing this AD to address the unsafe condition on these products.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
(1) This AD applies to The Boeing Company Model 737-600, -700, -
700C, -800, -900, and -900ER series airplanes, certificated in any
category, as identified in Boeing Alert Service Bulletin 737-
57A1327, Revision 1, dated September 28, 2016.
(2) Installation of Supplemental Type Certificate (STC)
ST00830SE (<a href="http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/354588EE63741A068625807D006726F6?OpenDocument&Highlight=st00830se">http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/354588EE63741A068625807D006726F6?OpenDocument&Highlight=st00830se</a>)
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.
Document Text
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[Federal Register Volume 82, Number 159 (Friday, August 18, 2017)]
[Rules and Regulations]
[Pages 39344-39347]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2017-16354]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2016-9112; Product Identifier 2016-NM-091-AD; Amendment
39-18982; AD 2017-16-05]
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 certain
The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER
series airplanes. 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. This AD requires a one-time
detailed visual inspection for discrepancies in the Krueger flap
bullnose attachment hardware, and related investigative and corrective
actions, if necessary. We are issuing this AD to address the unsafe
condition on these products.
DATES: This AD is effective September 22, 2017.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of September
22, 2017.
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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. 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. It is also available on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2016-
9112.
Examining the AD Docket
You may examine the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2016-
9112; 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: Alan Pohl, Aerospace Engineer,
Airframe Section, FAA, Seattle Aircraft Certification Office (ACO)
Branch, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6450; fax: 425-917-6590; email: <a href="/cdn-cgi/l/email-protection#ec8d808d82c29c838480ac8a8d8dc28b839a"><span class="__cf_email__" data-cfemail="d0b1bcb1befea0bfb8bc90b6b1b1feb7bfa6">[email protected]</span></a>.
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 certain The Boeing Company
Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes.
The NPRM published in the Federal Register on September 29, 2016 (81 FR
66874) (``the NPRM''). The NPRM was prompted by a report of a Krueger
flap bullnose departing an airplane during taxi, which caused damage to
the wing
[[Page 39345]]
structure and thrust reverser. The NPRM proposed 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. We are issuing this AD to detect and correct
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
Vincent Romano, a private citizen, and United Airlines (UAL),
stated their support for 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 NPRM as paragraph (c)(1) 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 Reference the Latest Service Information
All Nippon Airways (ANA), American Airlines (AAL), Boeing,
<a href="http://Jet2.com">Jet2.com</a>, TUIfly GmbH (HAP), UAL, and Kennedy Juma, requested revising
the NPRM to reference Boeing Alert Service Bulletin 737-57A1327,
Revision 1, dated September 28, 2016. Some commenters pointed out that
the original issue had some errors in the illustrations and needed
certain clarifications. ANA and Boeing also requested that we provide
credit for accomplishing the original issue of the service information.
We agree that this final rule should reference the latest service
information. Since we issued the NPRM, Boeing issued Boeing Alert
Service Bulletin 737-57A1327, Revision 1, dated September 28, 2016. We
have revised paragraphs (c)(1) (paragraph (c) of the proposed AD) and
(g) of this AD to reference Boeing Alert Service Bulletin 737-57A1327,
Revision 1, dated September 28, 2016, for accomplishment of the
required actions. We have also revised this AD to provide credit for
using Boeing Alert Service Bulletin 737-57A1327, dated May 20, 2016, to
accomplish the required actions before the effective date of this AD.
Request To Correct the Latest Service Information
AAL requested that Boeing Alert Service Bulletin 737-57A1327,
Revision 1, dated September 28, 2016, be corrected to address errors in
Figures 1, 2, 3, and 4. AAL stated that these errors affect the
depiction of how the clevis assembly, clevis, and bullnose hinge lug
are attached to each other, and suggested that revising the figures to
correct the errors would clarify which parts must be subject to the
detailed inspection.
We acknowledge that Figures 1, 2, 3, and 4 of Boeing Alert Service
Bulletin 737-57A1327, Revision 1, dated September 28, 2016, contain
errors in the labeling of parts in the illustrations. However, the
instructions in the tables in the figures correctly identify the parts
and actions to be accomplished. Since the instructions are correct, the
service bulletin adequately addresses the unsafe condition. We do not
revise manufacturers' service information. However, Boeing might decide
to revise Boeing Alert Service Bulletin 737-57A1327, Revision 1, dated
September 28, 2016, to correct the errors. We have not changed the AD
in this regard.
Request To Allow Alternate Replacement Procedure
AAL and Southwest Airlines (SWA) requested that we revise the NPRM
to provide an option to replace cracked or deformed bullnose hinge lugs
or clevis assemblies with bullnose hinge lugs or clevis assemblies
instead of replacement with a Krueger flap assembly, as specified in
paragraph 3.B.2.a.(1)(a)1) of Boeing Alert Service Bulletin 737-
57A1327, Revision 1, dated September 28, 2016. AAL suggested that the
replacement option could be done using certain sections of a component
maintenance manual (CMM). SWA suggested the use of Boeing production
installation drawings. Both AAL and SWA also stated that replacing only
the affected bullnose hinge lugs or clevis assemblies would also reduce
the cost of repair or replacement. SWA also stated that there is a
limited inventory of Krueger flap assemblies and that limited
inventory, combined with a 6-month compliance time could significantly
impair operators.
We understand that the suggested replacement option might reduce
the burden on operators. However, we do not agree to revise this AD to
include the suggested changes. The repairs provided by the suggested
sections of the CMM address normal wear-and-tear, and these repairs may
not be appropriate for addressing damage that might result from an
improperly attached Krueger flap. Boeing informed us that there is no
procedure in the CMM that would provide step-by-step instructions to
remove only the bullnose other than by use of the drawing system.
Engineering instructions would be needed to ensure that the remainder
of the flap assembly is serviceable and not damaged in addition to the
damaged bullnose hinge lugs or clevis assembly, and that level of
instruction would be too much detail for an AD. However, once we issue
this AD, any person may request approval of an AMOC under the
provisions of paragraph (i) of this AD. We have not changed the 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 changes described previously and minor editorial
changes. We have determined that these minor changes:
<bullet> Are consistent with the intent that was proposed in the
NPRM for correcting the unsafe condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM.
[[Page 39346]]
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 1,
dated September 28, 2016. The 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. 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 1,495 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 of the Krueger flap 3 work-hours x $85 per None................ $255 $381,225
bullnose hardware. hour = $255.
----------------------------------------------------------------------------------------------------------------
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 to
the Director of the System Oversight Division.
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):
2017-16-05 The Boeing Company: Amendment 39-18982; Docket No. FAA-
2016-9112; Product Identifier 2016-NM-091-AD.
(a) Effective Date
This AD is effective September 22, 2017.
(b) Affected ADs
None.
(c) Applicability
(1) This AD applies to The Boeing Company Model 737-600, -700, -
700C, -800, -900, and -900ER series airplanes, certificated in any
category, as identified in Boeing Alert Service Bulletin 737-
57A1327, Revision 1, dated September 28, 2016.
(2) Installation of Supplemental Type Certificate (STC)
ST00830SE (<a href="http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/354588EE63741A068625807D006726F6?OpenDocument&Highlight=st00830se">http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/354588EE63741A068625807D006726F6?OpenDocument&Highlight=st00830se</a>)
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. We are issuing this AD to detect and
correct 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) Inspection of the Krueger Flap Bullnose
Within 6 months after the effective date of this AD, do a
detailed inspection for discrepancies of the Krueger flap bullnose
attachment hardware, and do all applicable related investigative and
corrective actions,
[[Page 39347]]
in accordance with the Accomplishment Instructions of Boeing Alert
Service Bulletin 737-57A1327, Revision 1, dated September 28, 2016.
Do all applicable related investigative and corrective actions
before further flight.
(h) Credit for Previous Actions
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, dated May 20, 2016.
(i) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Seattle 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
(j)(1) of this AD. Information may be emailed to: <a href="/cdn-cgi/l/email-protection#5f66721e1112720c3a3e2b2b333a721e1c10721e12101c720d3a2e2a3a2c2b2c1f393e3e71383029"><span class="__cf_email__" data-cfemail="ecd5c1ada2a1c1bf898d98988089c1adafa3c1ada1a3afc1be899d99899f989fac8a8d8dc28b839a">[email protected]</span></a>.
(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) For service information that contains steps that are labeled
as Required for Compliance (RC), the provisions of paragraphs
(i)(4)(i) and (i)(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 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.
(j) Related Information
(1) For more information about this AD, contact Alan Pohl,
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 1601
Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6450; fax:
425-917-6590; email: <a href="/cdn-cgi/l/email-protection#6a0b060b04441a0502062a0c0b0b440d051c"><span class="__cf_email__" data-cfemail="ceafa2afa0e0bea1a6a28ea8afafe0a9a1b8">[email protected]</span></a>.
(2) Service information identified in this AD that is not
incorporated by reference is available at the addresses specified in
paragraphs (k)(3) and (k)(4) of this AD.
(k) 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 1, dated
September 28, 2016.
(ii) Reserved.
(3) For Boeing 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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(4) You may view this service information at FAA, Transport
Standards Branch, 1601 Lind Ave 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: <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Renton, Washington, on July 26, 2017.
Jeffrey E. Duven,
Director, System Oversight Division, Aircraft Certification Service.
[FR Doc. 2017-16354 Filed 8-17-17; 8:45 am]
BILLING CODE 4910-13-P
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