AD 2018-10-12
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 737-100 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-200 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-200C Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-300 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-400 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 737-500 Series | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Cracks in the left-side and right-side keel beam upper chords and both aft vertical stiffeners, which could result in the inability of the keel beam structure to sustain required flight loads, which could adversely affect the structural integrity of the airplane.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Accomplish the actions identified as "RC" (required for compliance) in the Accomplishment Instructions of Boeing Alert Requirements Bulletin 737-57A1339 RB, dated April 16, 2018, which includes repetitive surface HFEC and detailed inspections for cracking of the aft vertical stiffeners; repetitive detailed inspections for cracking of time-limited repairs; a one-time surface HFEC inspection for cracking of the keel beam upper chord inboard flanges and a general visual inspection for cracking of the associated angle; and applicable on-condition actions.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 50 flight hours
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
All The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This AD requires repetitive high frequency eddy current (HFEC) and detailed inspections, as applicable, for cracking of certain aft vertical stiffeners; repetitive detailed inspections for cracking of time-limited repairs, as applicable; a one-time HFEC inspection for cracking of the keel beam upper chord inboard flanges; a one-time general visual inspection for cracking of a certain angle; and applicable on-condition actions. This AD was prompted by a report of cracks in the left-side and right-side keel beam upper chords and aft vertical stiffeners. 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
This AD applies to all The Boeing Company Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, certificated in any
category.
Document Text
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[Federal Register Volume 83, Number 100 (Wednesday, May 23, 2018)]
[Rules and Regulations]
[Pages 23775-23778]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2018-10920]
========================================================================
Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
========================================================================
Federal Register / Vol. 83, No. 100 / Wednesday, May 23, 2018 / Rules
and Regulations
[[Page 23775]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2018-0446; Product Identifier 2018-NM-069-AD; Amendment
39-19288; AD 2018-10-12]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for all The
Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 series
airplanes. This AD requires repetitive high frequency eddy current
(HFEC) and detailed inspections, as applicable, for cracking of certain
aft vertical stiffeners; repetitive detailed inspections for cracking
of time-limited repairs, as applicable; a one-time HFEC inspection for
cracking of the keel beam upper chord inboard flanges; a one-time
general visual inspection for cracking of a certain angle; and
applicable on-condition actions. This AD was prompted by a report of
cracks in the left-side and right-side keel beam upper chords and aft
vertical stiffeners. We are issuing this AD to address the unsafe
condition on these products.
DATES: This AD is effective June 7, 2018.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of June 7,
2018.
We must receive comments on this AD by July 9, 2018.
ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
<bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the instructions for submitting comments.
<bullet> Fax: 202-493-2251.
<bullet> 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.
<bullet> 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 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 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 <a href="http://www.regulations.gov">http://www.regulations.gov</a> by
searching for and locating Docket No. FAA-2018-0446.
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-2018-
0446; 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 final rule, 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: Galib Abumeri, Aerospace Engineer,
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5324; fax: 562-627-
5210; email: <a href="/cdn-cgi/l/email-protection#a4e3c5c8cdc68ae5c6d1c9c1d6cde4c2c5c58ac3cbd2"><span class="__cf_email__" data-cfemail="4700262b2e25690625322a22352e0721262669202831">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We have received a report indicating that cracks were discovered in
the left-side and right-side keel beam upper chords and both aft
vertical stiffeners on an airplane that had accumulated 1,304 flight
cycles since the aft vertical stiffeners had been inspected in
accordance with Boeing Service Bulletin 737-57A1269. The Boeing Company
has done an analysis of the affected structure and found that the
actual stresses on aft vertical stiffeners at left buttock line (LBL)
and right buttock line (RBL) 6.15 are more than those used to design
the structure. The increased stresses cause fatigue cracks in the
stiffeners. If the aft vertical stiffeners have cracks or are severed,
the fatigue damage may extend into the adjacent keel beam structure.
The Boeing Company has determined that the existing inspections in
Boeing Service Bulletin 737-57A1269, required by AD 2005-20-01,
Amendment 39-14294 (70 FR 56358, September 27, 2005) (``AD 2005-20-
01''), do not provide sufficient inspection intervals for timely crack
detection in the aft vertical stiffeners. Cracking of the aft vertical
stiffeners, if not addressed, could result in the inability of the keel
beam structure to sustain required flight loads, which could adversely
affect the structural integrity of the airplane.
We have determined that both AD 2005-20-01 and this AD must be done
in order to address the identified unsafe condition. Boeing plans to
issue a revision to Service Bulletin 737-57A1269 in the near future and
at that time we may consider superseding AD 2005-20-01.
Related Service Information Under 1 CFR Part 51
We reviewed Boeing Alert Requirements Bulletin 737-57A1339 RB,
dated April 16, 2018. The service information describes procedures for
repetitive surface HFEC and detailed inspections for cracking of the
aft vertical stiffeners; repetitive detailed inspections for cracking
of time-limited repairs; a one-time surface HFEC inspection for
cracking of the keel beam upper chord inboard flanges and a general
visual inspection for cracking of the associated angle; and applicable
on-condition 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.
FAA's Determination
We are issuing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or
[[Page 23776]]
develop in other products of the same type design.
AD Requirements
This AD requires accomplishing the actions identified as ``RC''
(required for compliance) in the Accomplishment Instructions of Boeing
Alert Requirements Bulletin 737-57A1339 RB, dated April 16, 2018,
described previously, except for any differences identified as
exceptions in the regulatory text of this AD.
For information on the procedures and compliance times, see this
service information at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and
locating Docket No. FAA-2018-0446.
Explanation of Requirements Bulletin
The FAA worked in conjunction with industry, under the
Airworthiness Directives Implementation Aviation Rulemaking Committee
(AD ARC), to enhance the AD system. One enhancement is a process for
annotating which steps in the service information are ``required for
compliance'' (RC) with an AD. Boeing has implemented this RC concept
into Boeing service bulletins. In an effort to further improve the
quality of ADs and AD-related Boeing service information, a joint
process improvement initiative was worked between the FAA and Boeing.
The initiative resulted in the development of a new process in which
the service information more clearly identifies the actions needed to
address the unsafe condition in the ``Accomplishment Instructions.''
The new process results in a Boeing Requirements Bulletin, which
contains only the actions needed to address the unsafe condition (i.e.,
only the RC actions).
Interim Action
We consider this AD interim action. We are currently considering
requiring the replacement of the vertical stiffeners on certain
airplanes, which would constitute terminating action for certain
inspections required by this AD action. The planned compliance time for
replacing the vertical stiffeners would allow enough time to provide
notice and opportunity for prior public comment on the merits of the
modification.
FAA's Justification and Determination of the Effective Date
An unsafe condition exists that requires the immediate adoption of
this AD without providing an opportunity for public comments prior to
adoption. The FAA has found that the risk to the flying public
justifies waiving notice and comment prior to adoption of this rule
because cracks in the keel beam upper chords could result in the
inability of the keel beam structure to sustain required flight loads,
which could adversely affect the structural integrity of the airplane.
Therefore, we find good cause that notice and opportunity for prior
public comment are impracticable. In addition, for the reason(s) stated
above, we find that good cause exists for making this amendment
effective in less than 30 days.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety and was not preceded by notice and an opportunity for public
comment. However, we invite you to send any written data, views, or
arguments about this final rule. Send your comments to an address
listed under the ADDRESSES section. Include the docket number FAA-2018-
0446 and Product Identifier 2018-NM-069-AD at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this final rule. We will
consider all comments received by the closing date and may amend this
final rule because of those comments.
We will post all comments we receive, without change, to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this final rule.
Costs of Compliance
We estimate that this AD affects 67 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
----------------------------------------------------------------------------------------------------------------
Surface HFEC and detailed 2 work-hours x $85 $0 $170 per inspection Up to $11,390 per
inspections of aft vertical per hour = $170 per cycle. inspection cycle.
stiffeners (for inspection cycle.
Configuration 1 airplanes).
Detailed inspection of aft 2 work-hours x $85 0 $170 per inspection Up to $11,390 per
vertical stiffeners and time- per hour = $170. cycle. inspection cycle.
limited repair (for
Configuration 2 airplanes).
Surface HFEC inspection of 2 work-hours x $85 0 $170................ $11,390.
the keel beam upper chord per hour = $170.
inboard flanges and a
general visual inspection of
the angle (for all
airplanes).
----------------------------------------------------------------------------------------------------------------
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.
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
[[Page 23777]]
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
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):
2018-10-12 The Boeing Company: Amendment 39-19288; Docket No. FAA-
2018-0446; Product Identifier 2018-NM-069-AD.
(a) Effective Date
This AD is effective June 7, 2018.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all The Boeing Company Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, certificated in any
category.
(d) Subject
Air Transport Association (ATA) of America Code 57, Wings; 53,
Fuselage.
(e) Unsafe Condition
This AD was prompted by a report of cracks in the left-side and
right-side keel beam upper chords and aft vertical stiffeners.
Cracks in the aft vertical stiffeners may lead to the inability of
the keel beam structure to sustain required flight loads, which
could adversely affect the structural integrity of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions for Group 1 Airplanes
For airplanes identified as Group 1 in Boeing Alert Requirements
Bulletin 737-57A1339 RB, dated April 16, 2018: Within 120 days after
the effective date of this AD, inspect the airplane and do all
applicable corrective actions using a method approved in accordance
with the procedures specified in paragraph (k) of this AD.
(h) Required Actions for Group 2 Airplanes
Except as required by paragraph (i) of this AD: For airplanes
identified as Group 2 in Boeing Alert Requirements Bulletin 737-
57A1339 RB, dated April 16, 2018, at the applicable times specified
in the ``Compliance'' paragraph of Boeing Alert Requirements
Bulletin 737-57A1339 RB, dated April 16, 2018, do all applicable
actions identified in, and in accordance with, the Accomplishment
Instructions of Boeing Alert Requirements Bulletin 737-57A1339 RB,
dated April 16, 2018.
Note 1 to paragraph (h) of this AD: Guidance for accomplishing
the actions required by this AD can be found in Boeing Alert Service
Bulletin 737-57A1339, dated April 16, 2018, which is referred to in
Boeing Alert Requirements Bulletin 737-57A1339 RB, dated April 16,
2018.
(i) Exceptions to Service Information Specifications
(1) For purposes of determining compliance with the requirements
of this AD: Where Boeing Alert Requirements Bulletin 737-57A1339 RB,
dated April 16, 2018, uses the phrase ``the original issue date of
Requirements Bulletin 737-57A1339 RB,'' this AD requires using the
effective date of this AD.
(2) Where Boeing Alert Requirements Bulletin 737-57A1339 RB,
dated April 16, 2018, specifies contacting Boeing, this AD requires
repair using a method approved in accordance with the procedures
specified in paragraph (k) of this AD.
(j) Optional Terminating Action for Repetitive Inspections
Removal of the time-limited repair and accomplishment of
additional actions in accordance with the Accomplishment
Instructions of Boeing Alert Requirements Bulletin 737-57A1339 RB,
dated April 16, 2018, terminate the repetitive inspections of the
aft vertical stiffeners and time-limited repair, as specified in the
Accomplishment Instructions of Boeing Alert Requirements Bulletin
737-57A1339 RB, dated April 16, 2018, and required by paragraph (h)
of this AD.
(k) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Los Angeles 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: <a href="/cdn-cgi/l/email-protection#cff6e28e8182e2838e8e8c80e28e82808ce29daabebaaabcbbbc8fa9aeaee1a8a0b9"><span class="__cf_email__" data-cfemail="4c75610d020161000d0d0f03610d01030f611e293d39293f383f0c2a2d2d622b233a">[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, Los Angeles 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.
(l) Related Information
(1) For more information about this AD, contact Galib Abumeri,
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch,
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5324; fax: 562-627-5210; email: <a href="/cdn-cgi/l/email-protection#2760464b4e45096645524a42554e6741464609404851"><span class="__cf_email__" data-cfemail="3d7a5c51545f137c5f4850584f547d5b5c5c135a524b">[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 (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 Requirements Bulletin 737-57A1339 RB, dated
April 16, 2018.
(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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
(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
[[Page 23778]]
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 Des Moines, Washington, on May 11, 2018.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification
Service.
[FR Doc. 2018-10920 Filed 5-22-18; 8:45 am]
BILLING CODE 4910-13-P
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