[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 [www.gpo.gov]
[FR Doc No: 2020-11034]


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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.

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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 https://www.myboeingfleet.com. 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 https://www.regulations.gov by searching for and 
locating Docket No. FAA-2020-0096.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov 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: [email protected].

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:
     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.
    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
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                                                                                                 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: [email protected].
    (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: [email protected].
    (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 https://www.myboeingfleet.com.
    (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 [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    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]
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