[Federal Register Volume 88, Number 29 (Monday, February 13, 2023)]
[Rules and Regulations]
[Pages 9185-9188]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-02934]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-1050; Project Identifier AD-2021-01257-T; 
Amendment 39-22316; AD 2023-02-09]
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) 2007-10-
04, which applied to all McDonnell Douglas Model DC-9-81 (MD-81), DC-9-
82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and MD-88 airplanes. AD 
2007-10-04 required repetitive inspections to detect cracks in the 
horizontal stabilizer, and related investigative and corrective actions 
if necessary. Since the FAA issued AD 2007-10-04, it has been 
determined that certain compliance times and repetitive intervals must 
be reduced to address the unsafe condition. This AD continues to 
require the actions specified in AD 2007-10-04 with revised compliance 
times for certain actions. The FAA is issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective March 20, 2023.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of March 20, 
2023.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2022-1050; 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.
    Material Incorporated by Reference:
     For service information incorporated by reference 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; website myboeingfleet.com.
     You may view this service information at the FAA, 
Airworthiness

[[Page 9186]]

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 at regulations.gov under 
Docket No. FAA-2022-1050.

FOR FURTHER INFORMATION CONTACT: Manuel Hernandez, Aerospace Engineer, 
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount 
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5256; email: 
[email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to supersede AD 2007-10-04, Amendment 39-15045 (72 FR 
25960, May 8, 2007) (AD 2007-10-04). AD 2007-10-04 applied to all 
McDonnell Douglas Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-
83), DC-9-87 (MD-87), and MD-88 airplanes. The NPRM published in the 
Federal Register on September 15, 2022 (87 FR 56593). The NPRM was 
prompted by the determination that certain compliance times and 
repetitive intervals must be reduced for the high frequency eddy 
current (HFEC) surface and open hole inspections of the rear spar upper 
caps. The FAA received a report from Boeing of a crack found along 
fasteners in the upper rear spar that was longer than two inches during 
an inspection of the horizontal rear spar upper cap on a Model DC-9-82 
(MD-82) airplane with 69,799 flight hours and 38,520 flight cycles. The 
crack was discovered prior to the compliance time intervals for the 
repetitive inspections required by AD 2007-10-04; it was determined 
that certain compliance times do not provide at least two opportunities 
to reliably detect dual origin cracks before they reach critical 
length.
    In addition, since the FAA issued AD 2007-10-04, the legal name of 
the manufacturer has been changed from McDonnell Douglas Corporation to 
The Boeing Company on the most recent type certificate data sheet for 
the affected airplane models.
    In the NPRM, the FAA proposed to continue to require the actions 
specified in AD 2007-10-04, with revised compliance times for certain 
actions. The FAA is issuing this AD to detect and correct cracks in the 
upper and lower aft skin panels and rear spar upper caps, which, if not 
corrected, could lead to the loss of overall structural integrity of 
the horizontal stabilizer.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from one commenter, Boeing. The following 
presents the comments received on the NPRM and the FAA's response to 
each comment.

Request To Revise ``Related Service Information Under 1 CFR Part 51''

    Boeing requested that the FAA revise the description of the service 
information in the ``Related Service Information under 1 CFR part 51'' 
paragraph in the NPRM. The paragraph in the NPRM reads as follows: 
``Corrective actions include stop drilling the end of the crack, 
trimming out the crack and installing filler, installing a horizontal 
stabilizer upper and lower aft skin panel splice, replacing the 
horizontal stabilizer upper and lower aft skin panel, installing 
bushings and cold working holes, removing the crack and performing a 
repair, replacing the horizontal stabilizer rear spar upper cap splice, 
and replacing the splice repair with a new horizontal stabilizer rear 
spar upper cap.'' Boeing suggested the FAA revise the text to read: 
``Corrective actions to the horizontal stabilizer skin panel upper and 
lower aft skin panel include options for (1) stop drilling the end of 
the crack or trimming out the crack, and then doing a skin splice 
repair or replacing the skin at the given compliance time, (2) 
installing a skin panel splice, or (3) replacing the skin panel. 
Corrective actions to the horizontal stabilizer rear spar upper cap 
include options for (1) enlarging the hole to remove the crack, (2) 
performing a cap splice repair, (3) performing a cap splice repair and 
cold-working certain holes, (4) performing a cap replacement, or (5) 
performing a cap replacement and cold-working certain holes.'' Boeing 
reasoned that the revised text would distinguish between corrective 
actions specifically for skins and those for spar cap, per the Boeing 
Service Bulletin, and would also clarify that replacing a temporarily 
repaired structure is applicable only to the skin panel and not the 
spar cap; a repaired spar cap is inspected repetitively.
    The FAA agrees and revised the ``Related Service Information under 
1 CFR part 51'' paragraph in the final rule as requested.

Conclusion

    The FAA reviewed the relevant data, considered any comments 
received, and determined that air safety requires adopting this AD as 
proposed. Accordingly, the FAA is issuing this AD to address the unsafe 
condition on these products. Except for minor editorial changes, and 
any other changes described previously, this AD is adopted as proposed 
in the NPRM. None of the changes will increase the economic burden on 
any operator.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Service Bulletin MD80-55A065, 
Revision 2, dated October 11, 2021. This service information specifies 
procedures for repetitive eddy current inspections (HFEC or low 
frequency eddy current inspections, as applicable) of the horizontal 
stabilizer; and applicable corrective actions. Corrective actions to 
the horizontal stabilizer skin panel upper and lower aft skin panel 
include options for (1) stop drilling the end of the crack or trimming 
out the crack, and then doing a skin splice repair or replacing the 
skin at the given compliance time, (2) installing a skin panel splice, 
or (3) replacing the skin panel. Corrective actions to the horizontal 
stabilizer rear spar upper cap include options for (1) enlarging the 
hole to remove the crack, (2) performing a cap splice repair, (3) 
performing a cap splice repair and cold-working certain holes, (4) 
performing a cap replacement, or (5) performing a cap replacement and 
cold-working certain holes.
    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 ADDRESSES.

Costs of Compliance

    The FAA estimates that this AD affects 22 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Inspections (retained actions      8 work-hours x $85               $0  $680 per inspection  $14,960 per
 from AD 2007-10-04).               per hour = $680,                     cycle.               inspection cycle.
                                    per inspection
                                    cycle.

[[Page 9187]]

 
Inspections (new proposed action)  Up to 20 work-hours               0  Up to $1,700 per     Up to $37,400 per
                                    x $85 per hour =                     inspection cycle.    inspection cycle.
                                    $1,700 per
                                    inspection cycle.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
corrective actions (e.g., repairs, replacements, installation) that 
would be required based on the results of the inspection. The FAA has 
no way of determining the number of aircraft that might need these 
corrective actions:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
             Action                     Labor cost                Parts cost               Cost per product
----------------------------------------------------------------------------------------------------------------
Repair, replacement and          Up to 656 work-hours x   Up to $128,892...........  Up to $184,652.
 installation of upper or lower   $85 per hour = $55,760.
 aft skin panel or splice.
Stop drill repair..............  4 work-hours x $85 per   $0.......................  $340.
                                  hour = $340.
Trim out.......................  8 work-hours x $85 per   $0.......................  $680.
                                  hour = $680.
Install bushings and cold work.  26 work-hours x $85 per  $9,827...................  $12,037.
                                  hour = $2,210.
Crack removal and repair.......  6 work-hours x $85 per   $2,033...................  $2,543.
                                  hour = $510.
Replace rear spar upper cap....  368 work-hours x $85     $36,402..................  $67,682.
                                  per hour = $31,280.
----------------------------------------------------------------------------------------------------------------

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

    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.

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:
0
a. Removing Airworthiness Directive (AD) 2007-10-04, Amendment 39-15045 
(72 FR 25960, May 8, 2007); and
0
b. Adding the following new AD:

2023-02-09 The Boeing Company: Amendment 39-22316; Docket No. FAA-
2022-1050; Project Identifier AD-2021-01257-T.

(a) Effective Date

    This airworthiness directive (AD) is effective March 20, 2023.

(b) Affected ADs

    This AD replaces AD 2007-10-04, Amendment 39-15045 (72 FR 25960, 
May 8, 2007) (AD 2007-10-04).

(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), DC-9-87 (MD-87), and MD-88 
airplanes, certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 55, Stabilizers.

(e) Unsafe Condition

    This AD was prompted by reports of cracks found in the 
horizontal stabilizer in the upper and lower aft skin panels at the 
aft inboard corner at station XH = 8.2 and in the rear spar upper 
caps adjacent to the aft skin panel at station XH = 10.0; and by a 
determination that certain compliance times and inspection intervals 
must be reduced. The FAA is issuing this AD to detect and correct 
cracks in the upper and lower aft skin panels and rear spar upper 
caps, which, if not corrected, could lead to the loss of overall 
structural integrity of the horizontal stabilizer.

(f) Compliance

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

(g) Repetitive Inspections and Corrective 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 MD80-55A065, Revision 2, dated October 
11, 2021, do an eddy current inspection to detect any cracking in 
the horizontal stabilizer and do all applicable repetitive 
inspections and corrective actions, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD80-
55A065, Revision 2, dated October 11, 2021. Do all applicable 
repetitive inspections and corrective actions at the times specified 
in paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
MD80-55A065, Revision 2, dated October 11, 2021.

[[Page 9188]]

(h) Exceptions to Service Information Specifications

    (1) Where the Compliance Time columns of the tables in paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin MD80-55A065, 
Revision 2, dated October 11, 2021, use the phrase ``the original 
issue date of this service bulletin,'' this AD requires using May 
23, 2007 (the effective date of AD 2007-10-04).
    (2) Where the Compliance Time columns of the tables in paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin MD80-55A065, 
Revision 2, dated October 11, 2021, use the phrase ``the Revision 2 
date of this service bulletin,'' this AD requires using ``the 
effective date of this AD.''

(i) 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 the 
effective date of this AD using Boeing Alert Service Bulletin MD80-
55A065, dated April 25, 2007. This service information was 
incorporated by reference in AD 2007-10-04, Amendment 39-15045 (72 
FR 25960, May 8, 2007).
    (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 MD80-
55A065, Revision 1, dated September 23, 2008. This service 
information is not incorporated by reference in this AD.

(j) 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 responsible Flight Standards 
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 (k)(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 responsible Flight Standards 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 alteration deviation must 
meet the certification basis of the airplane, and the approval must 
specifically refer to this AD.
    (4) AMOCs approved for AD 2007-10-04 are approved as AMOCs for 
the corresponding provisions of Boeing Alert Service Bulletin MD80-
55A065, Revision 2, dated October 11, 2021, that are required by 
paragraph (g) of this AD, except the AMOCs specified in paragraphs 
(j)(4)(i) through (iii) of this AD are not approved as AMOCs for 
this AD.
    (i) FAA Letter Number 120L-14-226a, dated January 29, 2015.
    (ii) FAA Letter Number 120L-15-384b, dated November 2, 2015.
    (iii) FAA Letter Number 120L-10-345, dated August 3, 2010.

(k) Related Information

    (1) For more information about this AD, contact Manuel 
Hernandez, Aerospace Engineer, Airframe Section, FAA, Los Angeles 
ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; 
phone: 562-627-5256; email: [email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (l)(3) and (4) of this AD.

(l) 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 MD80-55A065, Revision 2, dated 
October 11, 2021.
    (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; website 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: www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on January 24, 2023.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2023-02934 Filed 2-10-23; 8:45 am]
BILLING CODE 4910-13-P


