Airworthiness Directives; Bell Textron Canada Limited Helicopters

[Federal Register Volume 86, Number 244 (Thursday, December 23, 2021)]
[Rules and Regulations]
[Pages 72833-72836]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-27645]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0728; Project Identifier MCAI-2020-00656-R; 
Amendment 39-21867; AD 2021-26-08]
RIN 2120-AA64


Airworthiness Directives; Bell Textron Canada Limited Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Bell Textron Canada Limited Model 206, 206A, 206A-1, 206B, 
206B-1, 206L, 206L-1, 206L-3, and 206L-4 helicopters. This AD was 
prompted by reports of cracked or missing nuts on the tail rotor drive 
shaft (TRDS) disc pack (Thomas) couplings. This AD requires removing 
certain nuts from service, installing newly designed nuts, and applying 
a specific torque and a torque stripe to each newly installed nut. This 
AD then requires, after the installation of each newly designed nut, 
inspecting the torque and, depending on the inspection results, either 
applying a torque stripe or performing further inspections and removing 
certain parts from service. Finally, this AD prohibits installing any 
affected nut on any TRDS Thomas coupling. The FAA is issuing this AD to 
address the unsafe condition on these products.

DATES: This AD is effective January 27, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of certain documents listed in this AD as of January 27, 
2022.

ADDRESSES: For service information identified in this final rule, 
contact Bell Textron Canada Limited, 12,800 Rue de l'Avenir, Mirabel, 
Quebec J7J 1R4, Canada; telephone 1-450-437-2862 or 1-800-363-8023; fax 
1-450-433-0272; email [email protected]; or at https://www.bellflight.com/support/contact-support. You may view the referenced 
service information at the FAA, Office of the Regional Counsel, 
Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort Worth, TX 
76177. For information on the availability of this material at the FAA, 
call (817) 222-5110. Service information that is incorporated by 
reference is also available at https://www.regulations.gov by searching 
for and locating Docket No. FAA-2021-0728.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0728; 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, the 
Transport Canada AD, any comments received, and other information. The 
street 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: Matt Fuller, AD Program Manager, 
General Aviation & Rotorcraft Unit, Airworthiness Products Section, 
Operational Safety Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 
76177; telephone (817) 222-5110; email [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to Bell Textron Canada 
Limited Model 206, 206A, 206A-1, 206B, 206B-1, 206L, 206L-1, 206L-3, 
and 206L-4 helicopters with nut part number (P/N) MS21042L4 or P/N 
MS21042L5 installed on the TRDS Thomas couplings. The NPRM published in 
the Federal Register on September 14, 2021 (86 FR 51038). In the NPRM, 
the FAA proposed to require, within 600 hours time-in-service (TIS) 
after the effective date of this AD, removing each affected nut from 
service, installing a newly designed nut, and applying a specific 
torque and a torque stripe to each newly installed nut. The NPRM also 
proposed to require, within 25 hours TIS after installation of each 
newly designed nut, inspecting the torque of each nut, and depending on 
the results of the inspection, further inspections and removing certain 
parts from service. Finally, the NPRM proposed to prohibit installing 
any affected nut on any TRDS Thomas coupling.
    The NPRM was prompted by a series of ADs issued by Transport 
Canada, which is the aviation authority for Canada. Initially, 
Transport Canada issued Canadian AD CF-2019-34, dated September 25, 
2019 (Transport Canada AD CF-2019-34), to correct an unsafe condition 
for Bell Helicopter Textron Canada Limited (now Bell Textron Canada 
Limited) Model 206, 206A, 206A-1, 206B, 206B-1, 206L, 206L-1, 206L-3, 
and 206L-4 helicopters, all serial numbers. Transport Canada AD

[[Page 72834]]

CF-2019-34 advised of reports of cracked or missing nuts at the TRDS 
Thomas couplings, which could have been caused by improper torque or 
hydrogen embrittlement. This condition, if not addressed, could result 
in loss of the tail rotor and subsequent loss of control of the 
helicopter.
    After Transport Canada issued Transport Canada AD CF-2019-34, it 
was determined that helicopters modified in accordance with 
Supplemental Type Certificate (STC) SH2750NM or Transport Canada STC 
SH99-202, were not able to comply with Transport Canada AD CF-2019-34. 
Accordingly, Transport Canada issued AD CF-2020-15, dated May 13, 2020 
(Transport Canada AD CF-2020-15) which supersedes Transport Canada AD 
CF-2019-34, and contains a new requirement for helicopters with STC 
SH2750NM or Transport Canada STC SH99-202 installed or models that have 
been modified per Bell Service Instruction BHT-206-SI-2052, Revision 1, 
dated October 14, 2010 (BHT-206-SI-2052). Transport Canada advises for 
certain model helicopters, the newly designed nuts cannot be installed 
because STC SH2750NM and Transport Canada STC SH99-202 install a pulley 
at the Thomas coupling location causing insufficient clearance. 
Transport Canada further advises for certain model helicopters with STC 
SH2750NM or Transport Canada STC SH99-202 installed, different part-
numbered nuts may be installed which were not identified in the 
applicable service information and are now required to be replaced with 
a new part-numbered nut that is not vulnerable to the unsafe condition. 
Accordingly, Air Comm Corporation, the STC holder for STC SH2750NM, 
issued new service information to address these additional issues and 
provide newly developed instructions which apply to certain model 
helicopters with STC SH2750NM or Transport Canada STC SH99-202 
installed.[FEDREG][VOL]*[/VOL][NO]*[/NO][DATE]*[/
DATE][RULES][RULE][PREAMB][AGENCY]*[/AGENCY][SUBJECT]*[/SUBJECT][/
PREAMB][SUPLINF][HED]*[/HED]
    Additionally, Transport Canada advises that BHT-206-SI-2052, which 
is optional, specifies procedures for Model 206L-1 and 206L-3 
helicopters to upgrade the airframe and systems and also includes 
installation of the Model 206L-4 TRDS Thomas coupling. According to 
Transport Canada, models that have incorporated BHT-206-SI-2052, with 
STC SH2750NM or Transport Canada STC SH99-202 installed, will have the 
Model 206L-4 helicopter pulley configuration and are subject to the Air 
Comm Corporation service information.
    Accordingly, Transport Canada AD CF-2020-15 requires the 
replacement of the affected nuts with the newly designed nuts at each 
TRDS Thomas coupling.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from one commenter; Bell. Bell 
recommended certain changes pertaining to the torque limits applied to 
each newly installed nut and the time for performing the torque 
recheck. The following presents the comments received on the NPRM and 
the FAA's response to each comment.
    Bell commented that the NPRM calls for an initial torque of 50 in/
lb to each nut, whereas the Bell maintenance manual requires an initial 
torque of 50-70 in/lb to each nut. Additionally, Bell explained that, 
as per its Standards Practice Manual (BHT-ALL-SPM) Chapter 2, tare 
torque must also be taken into consideration for self-locking hardware 
and that the total assembly torque is the measured tare torque plus the 
standard torque or specified torque. Bell requested that the 
installation torque in the AD be revised to read 50-70 in/lb.
    The FAA agrees that in this instance the maximum initial torque 
limit and the tare torque should be consistent with Bell's maintenance 
manuals and has revised this AD accordingly.
    Bell also commented that the NPRM calls for the torque recheck to 
be performed within 25 hours, whereas its maintenance manual requires 
the torque recheck between 10-25 hours. Bell recommended that the 
torque recheck be done within 25 hours TIS. The FAA agrees with the 
comment but no changes to this AD were necessary.

Conclusion

    These helicopters have been approved by the aviation authority of 
Canada and are approved for operation in the United States. Pursuant to 
the FAA's bilateral agreement with Canada, Transport Canada, its 
technical representative, has notified the FAA of the unsafe condition 
described in its AD. The FAA reviewed the relevant data, considered the 
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 helicopters. However, after the NPRM was 
published, the FAA discovered that costs were inadvertently excluded in 
the NPRM; those costs, which are nominal, are included in this final 
rule. Except for minor editorial changes, the change to the costs of 
compliance, and any other changes described previously, this AD is 
adopted as proposed in the NPRM. None of the changes will significantly 
increase the economic burden on any operator.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Bell Alert Service Bulletin 206-19-136, dated 
August 27, 2019 for FAA-certificated Model 206, 206A-series, and 206B-
series helicopters and non FAA-certificated Model TH-67 helicopters and 
Bell Alert Service Bulletin 206L-19-181, Revision A, dated August 29, 
2019 for Model 206L, 206L-1, 206L-3, and 206L-4 helicopters. This 
service information specifies procedures for replacing the affected 
nuts with the newly designed corrosion-resistant nuts.
    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.

Other Related Service Information

    The FAA reviewed Air Comm Corporation Service Bulletin SB 206EC-
092619, Revision NC, dated September 26, 2019, which also specifies 
procedures for replacing the affected nuts with the newly designed 
corrosion-resistant nuts, but explains that affected helicopters 
equipped with Air Comm Corporation air conditioning systems installed 
under STC SH2750NM use the affected nut to attach a pulley onto the 
TRDS, which causes clearance issues for the nuts to be installed at the 
coupling. Therefore, this service bulletin specifies replacing the nut 
with a lower profile nut.
    The FAA also reviewed BHT-206-SI-2052. This service information 
specifies procedures to upgrade Model 206L-1 and 206L-3 helicopters to 
allow operations at an increased internal gross weight.

Differences Between This AD and the Transport Canada AD

    Transport Canada AD CF-2020-15 requires compliance within 600 hours 
air time or within the next 24-months, whichever occurs first, whereas 
this AD requires compliance within 600 hours TIS and an additional 
inspection within 25 hours TIS after installation of certain nuts.

Costs of Compliance

    The FAA estimates that this AD affects 1,439 helicopters of U.S. 
Registry. Labor rates are estimated at $85 per work-hour. Based on 
these numbers, the FAA estimates the following costs to comply with 
this AD.

[[Page 72835]]

    Replacing each affected nut with the newly designed nut and 
applying torque and a torque stripe will take about 4 work-hours, and 
parts will cost about $75 for an estimated cost of $415 per nut 
replacement and $597,185 per nut replacement for the U.S. fleet.
    Checking the torque, and if applicable, applying a torque stripe, 
will take a minimal amount of time and have a nominal parts cost. If 
required, inspecting each TRDS Thomas coupling, and each bolt, nut, and 
washer for elongated holes and fretting on the fasteners will take 
about 0.5 work-hour for an estimated cost of $43 per inspection. 
Replacing each TRDS Thomas coupling will take about 4 work-hours, and 
parts will cost about $4,000 for an estimated cost of $4,340 per TRDS 
Thomas coupling replacement. Replacing each nut will take about 4 work-
hours, and parts will cost about $75 for an estimated cost of $415 per 
nut replacement. Replacing a bolt or washer will take a minimal amount 
of time and parts will cost a nominal amount.[FEDREG][VOL]*[/
VOL][NO]*[/NO][DATE]*[/DATE][RULES][RULE][PREAMB][AGENCY]*[/
AGENCY][SUBJECT]*[/SUBJECT][/PREAMB][SUPLINF][HED]*[/HED]

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 adding the following new airworthiness 
directive:

2021-26-08 Bell Textron Canada Limited: Amendment 39-21867; Docket 
No. FAA-2021-0728; Project Identifier MCAI-2020-00656-R.

(a) Effective Date

    This airworthiness directive (AD) is effective January 27, 2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Bell Textron Canada Limited Model 206, 206A, 
206A-1, 206B, 206B-1, 206L, 206L-1, 206L-3, and 206L-4 helicopters, 
certificated in any category, with nut part number (P/N) MS21042L4 
or P/N MS21042L5 installed on the tail rotor drive shaft (TRDS) disc 
pack (Thomas) couplings.
     Note 1 to paragraph (c): Helicopters with an OH-58A designation 
are Model 206A-1 helicopters.

(d) Subject

    Joint Aircraft Service Component (JASC) Code: 6510, Tail Rotor 
Drive Shaft.

(e) Unsafe Condition

    This AD was prompted by reports of cracked or missing nuts 
installed on the TRDS Thomas couplings. The FAA is issuing this AD 
to prevent failure or loss of a nut on the TRDS Thomas couplings. 
The unsafe condition, if not addressed, could result in loss of the 
tail rotor and subsequent loss of control of the helicopter.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.[FEDREG][VOL]*[/VOL][NO]*[/NO][DATE]*[/
DATE][RULES][RULE][PREAMB][AGENCY]*[/AGENCY][SUBJECT]*[/SUBJECT][/
PREAMB][SUPLINF][HED]*[/HED]

(g) Required Actions

    (1) Within 600 hours time-in-service (TIS) after the effective 
date of this AD:
    (i) For helicopters that have not been modified by installing 
Supplemental Type Certificate (STC) SH2750NM:
    (A) Remove each nut P/N MS21042L4 installed on each TRDS Thomas 
coupling from service, and replace with nut P/N NAS9926-4L. The 
location of nut P/N NAS9926-4L is depicted in Detail A Figure 1 of 
Bell Alert Service Bulletin (ASB) 206-19-136, dated August 27, 2019 
(ASB 206-19-136) or Bell ASB 206L-19-181, Revision A, dated August 
29, 2019 (ASB 206L-19-181), as applicable to your model helicopter.
    (B) Apply a torque of 5.65-7.90 Nm (50-70 in lb) plus tare 
torque to each nut installed as required by paragraph (g)(1)(i)(A) 
of this AD, and apply a torque stripe using torque seal lacquer (C-
049) or equivalent lacquer, as shown in Figure 2 of ASB 206-19-136 
or ASB 206L-19-181, as applicable to your model helicopter.
    Note 2 to paragraph (g)(1)(i)(B): Torque stripes are referred to 
as witness marks in ASB 206-19-136 and ASB 206L-19-181.
    (ii) For Bell Textron Canada Limited Model 206, 206A, 206A-1, 
206B, 206B-1, and 206L helicopters that have been modified by 
installing STC SH2750NM and Model 206L-1 and 206L-3 helicopters that 
have been modified by installing STC SH2750NM but have not been 
modified by accomplishing Bell Service Instruction BHT-206-SI-2052, 
Revision 1, dated October 14, 2010 (BHT-206-SI-2052):
    (A) Remove each nut P/N MS21042L4 installed on each TRDS Thomas 
coupling from service, except for nuts P/N MS21042L4 installed on 
the forward short TRDS Thomas coupling, and replace with nut P/N 
NAS9926-4L. The location of nut P/N NAS9926-4L is depicted in Detail 
A Figure 1 of ASB 206-19-136 or ASB 206L-19-181 as applicable to 
your model helicopter.
    (B) Remove each nut P/N MS21042L4 installed on the forward short 
TRDS Thomas coupling from service and replace with nut P/N 90-132L4.
    (C) For each nut installed as required by paragraphs 
(g)(1)(ii)(A) and (B) of this AD, apply a torque of 5.65-7.90 Nm 
(50-70 in lb) plus tare torque to each nut and apply a torque stripe 
using torque seal lacquer (C-049) or equivalent lacquer, as shown in 
Figure 2 of ASB 206-19-136 or ASB 206L-19-181, as applicable to your 
model helicopter.
    (iii) For Bell Textron Canada Limited Model 206L-1 and 206L-3 
helicopters that have been modified by installing STC SH2750NM and 
have been modified by accomplishing BHT-206-SI-2052:
    (A) Remove each nut P/N MS21042L4 installed on each TRDS Thomas 
coupling from service, except for nuts P/N MS21042L4 installed on 
the forward short TRDS Thomas coupling, and replace with nut P/N 
NAS9926-4L. The location of nut P/N NAS9926-4L is depicted in Detail 
A Figure 1 of ASB 206L-19-181.
    (B) Remove each nut P/N MS21042L4 installed on the forward short 
TRDS Thomas coupling from service and replace with nut P/N 90-132L4.

[[Page 72836]]

    (C) For each nut installed as required by paragraphs 
(g)(1)(iii)(A) and (B) of this AD, apply a torque of 5.65-7.90 Nm 
(50-70 in lb) plus tare torque to each nut, and apply a torque 
stripe using torque seal lacquer (C-049) or equivalent lacquer, as 
shown in Figure 2 of ASB 206L-19-181.
    (iv) For Bell Textron Canada Limited Model 206L-4 helicopters 
that have been modified by installing STC SH2750NM:
    (A) Remove each nut P/N MS21042L4 installed on each TRDS Thomas 
coupling from service, except for nuts P/N MS21042L4 installed on 
the forward short TRDS Thomas coupling, and replace with nut P/N 
NAS9926-4L. The location of nut P/N NAS9926-4L is depicted in Detail 
A Figure 1 of ASB 206L-19-181.
    (B) Remove from service each nut P/N MS21042L5 installed on the 
forward short TRDS Thomas coupling and replace with nut P/N 90-
132L5.
    (C) For each nut installed as required by paragraphs 
(g)(1)(iv)(A) and (B) of this AD, apply a torque of 5.65-7.90 Nm 
(50-70 in lb) plus tare torque to each nut, and apply a torque 
stripe using torque seal lacquer (C-049) or equivalent lacquer, as 
shown in Figure 2 of ASB 206L-19-181.
    (2) Within 25 hours TIS after installation of any nut P/N 
NAS9926-4L, P/N 90-132L4, or P/N 90-132L5, as required by paragraphs 
(g)(1)(i)(A), (ii)(A) and (B), (iii)(A) and (B), or (iv)(A) and (B) 
of this AD, apply a torque of 5.65 Nm (50 in lb) to each nut.
    (i) If the nut does not move, apply a torque stripe using torque 
seal lacquer (C-049) or equivalent lacquer, as shown in Figure 2 of 
ASB 206-19-136 or ASB 206L-19-181, as applicable to your model 
helicopter.
    (ii) If any nut moves, inspect each TRDS Thomas coupling and 
each bolt, nut, and washer for elongated holes and fretting on the 
fasteners. If any TRDS Thomas coupling has an elongated hole, remove 
the TRDS Thomas coupling from service. If any bolt, nut, or washer 
has any fretting, remove the affected part from service.
    (3) As of the effective date of this AD, do not install nut P/N 
MS21042L4 or MS21042L5 on any TRDS Thomas coupling.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation 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 International Validation Branch, send 
it to the attention of the person identified in paragraph (i)(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.

(i) Related Information

    (1) For more information about this AD, contact Matt Fuller, AD 
Program Manager, General Aviation & Rotorcraft Unit, Airworthiness 
Products Section, Operational Safety Branch, FAA, 10101 Hillwood 
Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email 
[email protected].[FEDREG][VOL]*[/VOL][NO]*[/NO][DATE]*[/
DATE][RULES][RULE][PREAMB][AGENCY]*[/AGENCY][SUBJECT]*[/SUBJECT][/
PREAMB][SUPLINF][HED]*[/HED]
    (2) Bell Service Instruction BHT-206-SI-2052, Revision 1, dated 
October 14, 2010, which is not incorporated by reference, contains 
additional information about the subject of this AD. This service 
information is available at the contact information specified in 
paragraphs (j)(3) and (4) of this AD.
    (3) The subject of this AD is addressed in Transport Canada AD 
CF-2020-15, dated May 13, 2020. You may view the Transport Canada AD 
at https://www.regulations.gov in Docket No. FAA-2021-0728.

(j) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference 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) Bell Alert Service Bulletin 206-19-136, dated August 27, 
2019.
    (ii) Bell Alert Service Bulletin 206L-19-181, Revision A, dated 
August 29, 2019.
    (3) For Bell service information identified in this AD, contact 
Bell Textron Canada Limited, 12,800 Rue de l'Avenir, Mirabel, Quebec 
J7J 1R4, Canada; telephone 1-450-437-2862 or 1-800-363-8023; fax 1-
450-433-0272; email [email protected]; or at https://www.bellflight.com/support/contact-support.
    (4) You may view this service information at the FAA, Office of 
the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 
6N-321, Fort Worth, TX 76177. For information on the availability of 
this material at the FAA, call (817) 222-5110.
    (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 December 12, 2021.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-27645 Filed 12-22-21; 8:45 am]
BILLING CODE 4910-13-P[FEDREG][VOL]*[/VOL][NO]*[/NO][DATE]*[/
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