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Published 2021-06-23 · Federal Register document 2021-13458

Airworthiness Directives; The Boeing Company Airplanes

Publication summary

The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-8 and 737-9 (737 MAX) airplanes. This AD was prompted by the determination that additional Certification Maintenance Requirements (CMRs) are necessary. This AD requires a revision of the existing maintenance or inspection program to incorporate three additional CMRs. The FAA is issuing this AD to address the unsafe condition on these products.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:24:08.106391+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2021-9c919420683447c6
Source row
results[210]
Raw source SHA-256
9c919420683447c683ad0c877cb886e341c11862be32b47c536a001b1d76dcb5

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2021-10-07
Effective date printed in this edition
2021-07-08
Read 10 complete recorded clauses
Effective Date
(a) Effective Date

    This airworthiness directive (AD) is effective July 8, 2021.

Exact source excerpt. Text positions 13178–13264, end exclusive, in the original decoded publication. SHA-256: 7829dc2643c7c72e77ea9911def383d6f8b670e38310696a90359075f9333137

Affected ADs
(b) Affected ADs

    None.

Exact source excerpt. Text positions 13264–13293, end exclusive, in the original decoded publication. SHA-256: 871a4afc60ceeae06e8010585055188633d616078500c45937092bfe892239c0

Applicability wording · Applicability
(c) Applicability

    This AD applies to The Boeing Company Model 737-8 and 737-9 
airplanes, certificated in any category, with an original 
airworthiness certificate or original export certificate of 
airworthiness issued before November 20, 2020.

Exact source excerpt. Text positions 13293–13545, end exclusive, in the original decoded publication. SHA-256: 7968eb58dc1abab345ca914d94df44d3e8473f668e3811e7baeaf08c2dca9e53

Subject
(d) Subject

    Air Transport Association (ATA) of America Code Codes 22, 
Autoflight; and 27, Flight controls.

Exact source excerpt. Text positions 13545–13659, end exclusive, in the original decoded publication. SHA-256: d8ea6da57c85ad9b2353b341abae7d77ff27805635c5d7eea63c28818c882413

Unsafe Condition
(e) Unsafe Condition

    This AD was prompted by a determination that additional 
Certification Maintenance Requirements (CMRs) are necessary. The FAA 
is issuing this AD to ensure the availability of certain flight 
control system functions through maintenance tests to verify that 
the functions have not failed; a potential latent failure of a 
flight control system function, as tested by these three CMR items, 
if combined with unusual flight maneuvers or with another flight 
control system failure, could result in reduced controllability of 
the airplane.

[[Page 32737]]

Exact source excerpt. Text positions 13659–14242, end exclusive, in the original decoded publication. SHA-256: 086c9afc8729abda206cf6380542738814b4c48f59202deee40b3c4ab71f5ff3

Compliance
(f) Compliance

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

Exact source excerpt. Text positions 14242–14344, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3

Maintenance or Inspection Program Revision
(g) Maintenance or Inspection Program Revision

    Within 30 days after the effective date of this AD, revise the 
existing maintenance or inspection program, as applicable, to 
incorporate the CMR item information identified in figure 1 to 
paragraph (g) of this AD. For airplanes that have exceeded the CMR 
interval, in total flight hours (FHs), for a required CMR item, the 
associated task must be done before further flight after revision of 
the maintenance or inspection program.
[GRAPHIC] [TIFF OMITTED] TR23JN21.020

    Note 1 to paragraph (g): The CMR tasks and intervals specified 
in figure 1 to paragraph (g) of this AD correspond to the items 
identified in Boeing Certification Maintenance Requirements Document 
D626A011-9-03, dated July 2020. The information in both sources is 
identical.

Exact source excerpt. Text positions 14344–15155, end exclusive, in the original decoded publication. SHA-256: 253b015f678bb72c3ddbb5351e5c7f04c6c4e7b178188f28dcc38cd3eba9f3a7

Alternative Methods of Compliance (AMOCs)
(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle 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 Related Information. 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.

Exact source excerpt. Text positions 15155–15872, end exclusive, in the original decoded publication. SHA-256: a74d9a36e0072856c68274b7b982b35f8e8d52b28235be76bfea809a11bb6850

Related Information
(i) Related Information

    For more information about this AD, contact Ken Fairhurst, 
Manager, Systems and Equipment Section, FAA, Seattle ACO Branch, 
2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-
3500; email: [email protected].

Exact source excerpt. Text positions 15872–16128, end exclusive, in the original decoded publication. SHA-256: 6c183c0daa860f2b6d62142665daddfa501b010079bdf05441fc12bb7fae535c

Material Incorporated by Reference
(j) Material Incorporated by Reference

    None.

Exact source excerpt. Text positions 16128–16179, end exclusive, in the original decoded publication. SHA-256: 9d583edbcf085b1fae94c8be8274ba3ce59b91db7bf15c5f5fd81fff2816eec7

No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.

Find all recorded historical references to AD 2021-10-07 · 0 printed reference observations in this pinned collection.

These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.

Why these observations are shown

They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.

Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 7f82e2caf4cf493089e799f12b795333337cdb6311d48fc6cd9c61d14ff4683c. Source manifest: 50acb6a629901f68b835befdccb6f024b2a915615460d3313bf1147613294551.

Official source · 2021-06-23

Publication text

This is the complete recorded text of this dated publication.

Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.

Read the complete official publication text
[Federal Register Volume 86, Number 118 (Wednesday, June 23, 2021)]
[Rules and Regulations]
[Pages 32735-32737]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-13458]



[[Page 32735]]

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0013; Project Identifier AD-2021-00087-T; 
Amendment 39-21540; AD 2021-10-07]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain The Boeing Company Model 737-8 and 737-9 (737 MAX) airplanes. 
This AD was prompted by the determination that additional Certification 
Maintenance Requirements (CMRs) are necessary. This AD requires a 
revision of the existing maintenance or inspection program to 
incorporate three additional CMRs. The FAA is issuing this AD to 
address the unsafe condition on these products.

DATES: This AD is effective July 8, 2021.
    The FAA must receive comments on this AD by August 9, 2021.

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 https://www.regulations.gov. 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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0013; 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 street address for the 
Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Ken Fairhurst, Manager, Systems and 
Equipment Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des 
Moines, WA 98198; phone and fax: 206-231-3500; email: [email protected].

SUPPLEMENTARY INFORMATION:

Background

    Modern transport category airplanes can remain in service for 
decades. To ensure that an airplane's critical systems and back-up 
systems continue to meet FAA requirements, such as those in 14 CFR 
25.1309, manufacturers may develop and rely on required actions that 
include CMRs. CMRs are limitations documented in the airplane's 
instructions for continued airworthiness (ICA) that require operators 
to periodically check systems or replace certain equipment in order to 
ensure the continued availability and functionality of those systems 
over time.\1\ Air carriers have existing programs to schedule CMRs and 
comply with their requirements.
---------------------------------------------------------------------------

    \1\ More detailed information on CMRs can be found in FAA 
Advisory Circular (AC) 25-19A, ``Certification Maintenance 
Requirements,'' available at rgl.faa.gov.
---------------------------------------------------------------------------

    The FAA's recent review of the 737 MAX flight control system 
resulted in the determination that three additional CMR items are 
necessary to ensure the continued functioning of certain systems 
throughout the life of the airplane. The manufacturer proposed, and the 
FAA reviewed and approved, these three new CMRs (i.e., 22-CMR-01, 22-
CMR-02, and 27-CMR-09), which are described in Boeing Certification 
Maintenance Requirements Document D626A011-9-03, dated July 2020, and 
available in the docket for this AD.
    Prior to return to service, initial inspections of these systems 
were completed when necessary on affected airplanes; this ensured the 
safety of the 737 MAX return to service. Due to most of the fleet being 
well below flight-hour thresholds that would require inspection, and 
Boeing's coordination with operators of affected airplanes to do 
initial inspections prior to return to service, the FAA determined this 
AD to incorporate the new CMR items could be issued subsequent to 
return to service. Consistent with that approach, Boeing released a 
Multi-Operator Message. This approach protects both the safety of the 
return to service and the long term safety of the fleet.
    For newly produced airplanes, Boeing has incorporated the three 
additional CMRs into the ICA for every airplane delivered on or after 
November 20, 2020 (the effective date of AD 2020-24-02 (85 FR 74560, 
November 20, 2020) (AD 2020-24-02)). These CMRs have also already been 
incorporated into the maintenance programs for all U.S.-registered 737 
MAX airplanes that had been delivered before the effective date of AD 
2020-24-02 and are included in the applicability of AD 2020-24-02.
    The manufacturer has also communicated guidance to incorporate 
these CMRs into the maintenance programs of all affected 737 MAX 
operators, via Boeing Multi Operator Message MOM-MOM-20-0891-01B, dated 
December 22, 2020.
    Since these CMRs are part of the ICA for all 737 MAX airplanes 
delivered on or after November 20, 2020 (the effective date of AD 2020-
24-02), this AD is applicable only to airplanes with an original 
airworthiness certificate or original export certificate of 
airworthiness issued prior to that date.
    These CMRs are necessary because a potential latent failure of a 
flight control system function, as tested by one of these three CMRs, 
if combined with unusual flight maneuvers or with another flight 
control system failure, could result in reduced controllability of the 
airplane.
    After these CMRs have been incorporated into the operator's 
maintenance and inspection program, they may be treated as other CMRs 
on the airplane (i.e., operators may propose any change, escalation, or 
cancellation of these CMRs by following the processes described in AC 
25-19A, and no AMOC would be required).

FAA's Determination

    The FAA is issuing this AD because the agency has determined the 
unsafe condition described previously is likely to exist or develop in 
other products of the same type design.

AD Requirements

    This AD requires a revision of the existing maintenance or 
inspection program, as applicable, to incorporate additional CMR item 
information.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 
U.S.C. 551 et seq.) authorizes agencies to dispense with notice and 
comment procedures for rules when the agency, for ``good cause,'' finds 
that those procedures are ``impracticable, unnecessary, or contrary to 
the public interest.'' Under this section, an agency, upon finding good 
cause, may issue a final rule without providing notice and seeking 
comment prior to issuance. Further, section 553(d) of the APA 
authorizes agencies to make rules effective in less than thirty days, 
upon a finding of good cause.

[[Page 32736]]

    As discussed previously, all U.S.-registered airplanes are already 
in compliance with the requirements of this AD. Accordingly, notice and 
opportunity for prior public comment are unnecessary, pursuant to 5 
U.S.C. 553(b)(3). In addition, for the foregoing reason, the FAA finds 
that good cause exists pursuant to 5 U.S.C. 553(d) for making this 
amendment effective in less than 30 days.

Comments Invited

    The FAA invites you to send any written data, views, or arguments 
about this final rule. Send your comments to an address listed under 
ADDRESSES. Include Docket No. FAA-2021-0013 and Project Identifier AD-
2021-00087-T at the beginning of your comments. The most helpful 
comments reference a specific portion of the final rule, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
this final rule because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this final rule.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this AD contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this AD, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this AD. Submissions containing CBI should be sent to Ken 
Fairhurst, Manager, Systems and Equipment Section, FAA, Seattle ACO 
Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-
231-3500; email: [email protected]. Any commentary that the 
FAA receives that is not specifically designated as CBI will be placed 
in the public docket for this rulemaking.

Regulatory Flexibility Act

    The requirements of the Regulatory Flexibility Act (RFA) do not 
apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt 
a rule without prior notice and comment. Because the FAA has determined 
that it has good cause to adopt this rule without notice and comment, 
RFA analysis is not required.

Costs of Compliance

    Although the FAA estimates that 72 airplanes of U.S. registry are 
included in the applicability of this AD, all of these airplanes are 
already in compliance with the requirements of this AD. Nevertheless, 
the FAA provides the following cost estimate.
    The FAA has determined that revising the existing maintenance or 
inspection program takes an average of 90 work-hours per operator, 
although the agency recognizes that this number may vary from operator 
to operator. Since operators incorporate maintenance or inspection 
program changes for their affected fleets, the FAA has determined that 
a per-operator estimate is more accurate than a per-airplane estimate. 
Therefore, the FAA estimates the average total cost per operator to be 
$7,650 (90 work-hours x $85 per work-hour).

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, and
    (2) Will not affect intrastate aviation in Alaska.

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:

2021-10-07 The Boeing Company: Amendment 39-21540; Docket No. FAA-
2021-0013; Project Identifier AD-2021-00407-T.

(a) Effective Date

    This airworthiness directive (AD) is effective July 8, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 737-8 and 737-9 
airplanes, certificated in any category, with an original 
airworthiness certificate or original export certificate of 
airworthiness issued before November 20, 2020.

(d) Subject

    Air Transport Association (ATA) of America Code Codes 22, 
Autoflight; and 27, Flight controls.

(e) Unsafe Condition

    This AD was prompted by a determination that additional 
Certification Maintenance Requirements (CMRs) are necessary. The FAA 
is issuing this AD to ensure the availability of certain flight 
control system functions through maintenance tests to verify that 
the functions have not failed; a potential latent failure of a 
flight control system function, as tested by these three CMR items, 
if combined with unusual flight maneuvers or with another flight 
control system failure, could result in reduced controllability of 
the airplane.

[[Page 32737]]

(f) Compliance

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

(g) Maintenance or Inspection Program Revision

    Within 30 days after the effective date of this AD, revise the 
existing maintenance or inspection program, as applicable, to 
incorporate the CMR item information identified in figure 1 to 
paragraph (g) of this AD. For airplanes that have exceeded the CMR 
interval, in total flight hours (FHs), for a required CMR item, the 
associated task must be done before further flight after revision of 
the maintenance or inspection program.
[GRAPHIC] [TIFF OMITTED] TR23JN21.020

    Note 1 to paragraph (g): The CMR tasks and intervals specified 
in figure 1 to paragraph (g) of this AD correspond to the items 
identified in Boeing Certification Maintenance Requirements Document 
D626A011-9-03, dated July 2020. The information in both sources is 
identical.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle 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 Related Information. 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.

(i) Related Information

    For more information about this AD, contact Ken Fairhurst, 
Manager, Systems and Equipment Section, FAA, Seattle ACO Branch, 
2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-231-
3500; email: [email protected].

(j) Material Incorporated by Reference

    None.

    Issued on June 9, 2021.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-13458 Filed 6-21-21; 4:15 pm]
BILLING CODE 4910-13-P


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Text SHA-256
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These are dated publication metadata, recorded clauses and literal source observations. Word, model-label, header and reference matches do not establish current legal effect, manufacturer/model identity, aircraft applicability, installed configuration or compliance.

The collection uses 33 explicit annual source snapshots. Source captures and operative-text qualifications have separate states. Missing information remains unknown.