AD 2020-10-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | DC-9-81 (MD-81) | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | DC-9-82 (MD-82) | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | DC-9-83 (MD-83) | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | DC-9-87 (MD-87) | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | MD-88 | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Cracking in the center wing lower skin could cause structural failure of the wings.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Perform repetitive eddy current high frequency (ETHF) inspections for any cracking in the left and right side center wing lower skin, and repair if any crack is found. Expand the inspection area to include adjacent stringers with similar stress levels and perform repetitive inspections with increased sensitivity for crack detection. Perform repetitive eddy current low frequency (ETLF) inspections of the left and right side fastener holes and the forward and aft skins at certain locations for any cracking.
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
The Boeing Company Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes, and Model MD-88 airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
The FAA is superseding Airworthiness Directive (AD) 2016-07- 28, which applied to all The Boeing Company Model DC-9-81 (MD-81), DC- 9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes, and Model MD-88 airplanes. AD 2016-07-28 required repetitive eddy current high frequency (ETHF) inspections for any cracking in the left and right side center wing lower skin, and repair if any crack was found. This AD continues to require repetitive ETHF inspections for any cracking in the left and right side center wing lower skin, and repair if any crack is found. This AD also requires expanding the inspection area to include adjacent stringers with similar stress levels and to perform repetitive inspections with increased sensitivity for crack detection. This AD was prompted by a report of a crack at a certain stringer not addressed by AD 2016-07-28, and cracks at certain other stringers and associated end fittings, and skins in the center wing fuel tank where the stringers meet the end fittings addressed by AD 2016-07-28. The FAA is 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 DC-9-81 (MD-81),
DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes, and
Model MD-88 airplanes, certificated in any category.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 85, Number 100 (Friday, May 22, 2020)]
[Rules and Regulations]
[Pages 31046-31049]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2020-11034]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0096; Product Identifier 2019-NM-211-AD; Amendment
39-19913; AD 2020-10-10]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2016-07-
28, which applied to all The Boeing Company Model DC-9-81 (MD-81), DC-
9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes, and Model
MD-88 airplanes. AD 2016-07-28 required repetitive eddy current high
frequency (ETHF) inspections for any cracking in the left and right
side center wing lower skin, and repair if any crack was found. This AD
continues to require repetitive ETHF inspections for any cracking in
the left and right side center wing lower skin, and repair if any crack
is found. This AD also requires expanding the inspection area to
include adjacent stringers with similar stress levels and to perform
repetitive inspections with increased sensitivity for crack detection.
This AD was prompted by a report of a crack at a certain stringer not
addressed by AD 2016-07-28, and cracks at certain other
[[Page 31047]]
stringers and associated end fittings, and skins in the center wing
fuel tank where the stringers meet the end fittings addressed by AD
2016-07-28. The FAA is issuing this AD to address the unsafe condition
on these products.
DATES: This AD is effective June 26, 2020.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of June 26,
2020.
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 service information at the
FAA, Airworthiness Products Section, Operational Safety 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="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and
locating Docket No. FAA-2020-0096.
Examining the AD Docket
You may examine the AD docket on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2020-
0096; 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, any comments received, and other information. The
address for Docket Operations is 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: Mohit Garg, Aerospace Engineer,
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5264; fax: 562-627-
5210; email: <a href="/cdn-cgi/l/email-protection#0d6062656479236a6c7f6a4d6b6c6c236a627b"><span class="__cf_email__" data-cfemail="25484a4d4c510b42445742654344440b424a53">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to supersede AD 2016-07-28, Amendment 39-18473 (81 FR
21253, April 11, 2016) (``AD 2016-07-28''). AD 2016-07-28 applied to
all The Boeing Company Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83
(MD-83), and DC-9-87 (MD-87) airplanes, and Model MD-88 airplanes. The
NPRM published in the Federal Register on February 13, 2020 (85 FR
8209). The NPRM was prompted by a report of a crack at stringer S-13
which was not addressed by AD 2016-07-28, and by reports of cracks at
stringers S-15, S-16, or S-17 and associated end fittings, and skins in
the center wing fuel tank where the stringers meet the end fittings,
which were addressed by AD 2016-07-28. The NPRM proposed to continue to
require repetitive ETHF inspections for any cracking in the left and
right side center wing lower skin, and repair if any crack is found.
The NPRM also proposed to require expanding the inspection type and
area to include repetitive eddy current low frequency (ETLF)
inspections of the left and right side fastener holes and the forward
and aft skins at certain locations for any cracking. The FAA is issuing
this AD to detect and correct cracking in the center wing lower skin.
Such cracking could cause structural failure of the wings.
Comments
The FAA gave the public the opportunity to participate in
developing this AD. The following represents the comment received on
the NPRM and the FAA's response to that comment.
Request To Clarify Actions Since AD 2016-07-28 Was Issued
Boeing requested a correction in the ``Actions Since AD 2016-07-28
Was Issued'' section of the NPRM. Boeing stated that the wording in the
section suggests that there have been crack reports for other stringers
not addressed in AD 2016-07-28 beyond the single crack report for
stringer S-13, and that these additional reports are the reason for
expanding the inspection area. Boeing reiterated that AD 2016-07-28
addresses stringers S-15, S-16, and S-17, and, with the exception of
the single crack report for stringer S-13, the scope of stringers
reported cracked since the issuance of AD 2016-07-28 has not increased.
Boeing contends that the reason for the new ruling is to expand the
inspection area to include adjacent stringers with similar stress
levels and to perform a new inspection with increased crack detection,
as stated in the NPRM. Boeing stated that the first sentence in the
``Actions Since AD 2016-07-28 Was Issued'' section of the NPRM should
read, ``Since the FAA issued AD 2016-07-28, a single occurrence of
cracking has been found in stringer S-13, which is the only area not
addressed by AD 2016-07-28.''
The FAA agrees that the description in the NPRM is inaccurate.
Since that section of the preamble does not reappear in the final rule,
the requested change to the final rule is not necessary. However, the
FAA has changed the SUMMARY and Discussion section of the preamble, and
paragraph (e) of this AD, to reflect that this AD was prompted by the
single crack report at stringer S-13, and that stringer S-13 was not
covered by AD 2016-07-28.
Conclusion
The FAA reviewed the relevant data, considered the comment
received, and determined that air safety and the public interest
require adopting this AD with the changes described previously, and
minor editorial changes. The FAA has determined that these minor
changes:
<bullet> Are consistent with the intent that was proposed in the
NPRM for addressing the unsafe condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM.
The FAA 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
The FAA reviewed Boeing Alert Service Bulletin MD80-57A244,
Revision 1, dated October 1, 2019. This service information describes
procedures for a general visual inspection (GVI) for existing repairs;
repetitive ETLF inspections of the left and right side fastener holes
common to stringers 11 through 22 and the forward and aft skins for any
crack; repetitive ETHF inspections of the lower skin at stringers 18
through 20 for any crack; an ETHF inspection of the left side and right
side center wing lower skin for any crack; and applicable on-condition
actions. On-condition actions include repair and an internal GVI for
any cracks in stringers 11 through 22 between Xcw=0.0 and Xcw=20.0.
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
The FAA estimates that this AD affects 288 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
[[Page 31048]]
Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
Inspection (retained actions from 14 work-hours x $85 $0 $1,190 per $342,720 per
AD 2016[dash]07[dash]28). per hour = $1,190 inspection cycle. inspection cycle.
per inspection
cycle.
Expanded inspection (new action). Up to 48 work-hours 0 Up to $4,080 per Up to $1,175,040
x $85 per hour = inspection cycle. per inspection
Up to $4,080 per cycle.
inspection cycle.
----------------------------------------------------------------------------------------------------------------
The FAA has received no definitive data that would enable the
agency 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.
The FAA is 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
The FAA has 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) Will not affect intrastate aviation in Alaska, and
(3) 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)
2016-07-28, Amendment 39-18473 (81 FR 21253, April 11, 2016), and
adding the following new AD:
2020-10-10 The Boeing Company: Amendment 39-19913; Docket No. FAA-
2020-0096; Product Identifier 2019-NM-211-AD.
(a) Effective Date
This AD is effective June 26, 2020.
(b) Affected ADs
This AD replaces AD 2016-07-28, Amendment 39-18473 (81 FR 21253,
April 11, 2016) (``AD 2016-07-28'').
(c) Applicability
This AD applies to all The Boeing Company Model DC-9-81 (MD-81),
DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes, and
Model MD-88 airplanes, certificated in any category.
(d) Subject
Air Transport Association (ATA) of America Code 57, Wings.
(e) Unsafe Condition
This AD was prompted by a report of a crack at a certain
stringer not addressed by AD 2016-07-28, and cracks at certain other
stringers and associated end fittings, and skins in the center wing
fuel tank where the stringers meet the end fittings addressed by AD
2016-07-28. The FAA is issuing this AD to detect and correct
cracking in the center wing lower skin. Such cracking could cause
structural failure of the wings.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
Except as specified in paragraph (h) of this AD: At the
applicable times specified in paragraph 1.E., ``Compliance,'' of
Boeing Alert Service Bulletin MD80-57A244, Revision 1, dated October
1, 2019, do all applicable actions identified as ``RC'' (required
for compliance) in, and in accordance with, the Accomplishment
Instructions of Boeing Alert Service Bulletin MD80-57A244, Revision
1, dated October 1, 2019.
Note 1 to paragraph (g) of this AD: Boeing Alert Service
Bulletin MD80-57A244, Revision 1, dated October 1, 2019, refers to
Drawing SN09570007 for certain inspection sequences. If the pages of
Drawing SN09570007 are illegible, guidance can be found in Boeing
Multi Operator Message MOM-MOM-19-0549-01B, dated October 4, 2019.
(h) Exception to Service Information Specifications
Where Boeing Alert Service Bulletin MD80-57A244, Revision 1,
dated October 1, 2019, specifies contacting Boeing for repair
instructions or for alternative inspections: This AD requires doing
the repair, or doing the alternative inspections and applicable on-
condition actions before further flight using a method approved in
accordance with the procedures specified in paragraph (i) of this
AD.
(i) 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 (j)(1) of this AD. Information
may be emailed to: <a href="/cdn-cgi/l/email-protection#281105696665056469696b67056965676b057a4d595d4d5b5c5b684e4949064f475e"><span class="__cf_email__" data-cfemail="b58c98f4fbf898f9f4f4f6fa98f4f8faf698e7d0c4c0d0c6c1c6f5d3d4d49bd2dac3">[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 Company Organization Designation
Authorization (ODA) that has been authorized by the Manager, Los
Angeles ACO Branch, FAA, to make those findings. To be approved, the
repair method, modification deviation, or
[[Page 31049]]
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 2016-07-28 are not approved
as AMOCs for this AD.
(5) For service information that contains steps that are labeled
as Required for Compliance (RC), the provisions of paragraphs
(i)(5)(i) and (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.
(j) Related Information
(1) For more information about this AD, contact Mohit Garg,
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch,
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5264; fax: 562-627-5210; email: <a href="/cdn-cgi/l/email-protection#5e333136372a70393f2c391e383f3f70393128"><span class="__cf_email__" data-cfemail="e8858780819cc68f899a8fa88e8989c68f879e">[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 (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 MD80-57A244, Revision 1, dated
October 1, 2019.
(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,
Airworthiness Products Section, Operational Safety 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, email <a href="/cdn-cgi/l/email-protection#3e585b5a4c5b5910525b595f527e505f4c5f10595148"><span class="__cf_email__" data-cfemail="f5939091879092db9990929499b59b948794db929a83">[email protected]</span></a>, or go to: <a href="https://www.archives.gov/federal-register/cfr/ibr-locations.html">https://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued on May 14, 2020.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness
Division, Aircraft Certification Service.
[FR Doc. 2020-11034 Filed 5-21-20; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 6, 2026
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