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Airworthiness Directive packet

AD 2021-18-10

Airworthiness Directives; Bell Textron Canada Limited Helicopters

1 · Quick read — prepared by AircraftDirectives

Our plain-language summary — not the regulation

Requires revising the existing Rotorcraft Flight Manual (RFM) for your helicopter.

AD number
2021-18-10
Federal Register document
2021-19049
Citation
86 FR 49909
Amendment
39-21711
Docket
Docket No. FAA-2021-0497
Action
Final rule.
Published
2021-09-07
Effective
2021-10-12
Effective (as stated in the rule)
This AD is effective October 12, 2021.
Issued by
Transportation Department, Federal Aviation Administration
Regulation
14 CFR 39
Applies to (in our index)
Bell 429

2 · Official Federal Register document — government source, verbatim

Reproduced unedited from the Federal Register
[Federal Register Volume 86, Number 170 (Tuesday, September 7, 2021)]
[Rules and Regulations]
[Pages 49909-49912]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-19049]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0497; Project Identifier 2019-SW-043-AD; Amendment 
39-21711; AD 2021-18-10]
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 429 helicopters. This AD was 
prompted by three reports of unexpected forces or uncommanded inputs to 
the directional (yaw) control system. This AD requires revising the 
existing Rotorcraft Flight

[[Page 49910]]

Manual (RFM) for your helicopter. The FAA is issuing this AD to address 
the unsafe condition on these products.

DATES: This AD is effective October 12, 2021.

ADDRESSES: For service information identified in this final rule, 
contact Bell Textron Canada Limited, 12,800 Rue de l'Avenir, Mirabel, 
Quebec J7J1R4, Canada; telephone (450) 437-2862 or (800) 363-8023; fax 
(450) 433-0272; or at https://www.bellcustomer.com. 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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0497; 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: Mitch Soth, Flight Test Engineer, 
Southwest Section, Flight Test Branch, Compliance & Airworthiness 
Division, 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 429 helicopters, serial numbers 57001 and subsequent. The 
NPRM published in the Federal Register on July 7, 2021 (86 FR 35692). 
In the NPRM, the FAA proposed to require revising the existing RFM for 
your helicopter by adding procedures in Section 2, Normal Procedures, 
under 2-4. INTERIOR AND PRESTART CHECK, 2-5. ENGINE START, and 2-8. 
TAKEOFF; Section 3, Emergency and Malfunction Procedures, under 3-9. 
AUTOMATIC FLIGHT CONTROL SYSTEM; and Section 4, Performance, under 4-2. 
POWER ASSURANCE CHECK. The owner/operator (pilot) may revise the 
existing RFM for your helicopter, and the owner/operator must enter 
compliance with the applicable paragraphs of the AD into the aircraft 
records in accordance with Sec.  43.9(a)(1) through (4) and Sec.  
91.417(a)(2)(v). This is an exception to the FAA's standard maintenance 
regulations.
    The NPRM was prompted by Transport Canada Emergency AD CF-2019-16, 
dated May 6, 2019 (Transport Canada AD CF-2019-16), issued by Transport 
Canada, which is the aviation authority for Canada to correct an unsafe 
condition for Bell Helicopter Textron Canada Limited (now Bell Textron 
Canada Limited) Model 429 helicopters, serial numbers 57001 and 
subsequent. Transport Canada advises of three reports of unexpected 
forces or uncommanded inputs to the directional (yaw) control system 
during ground operations. Investigation revealed that a yaw trim 
runaway can occur while the automatic pedal trim function is operating. 
This condition, if not addressed, could result in loss of control of 
the helicopter. Accordingly, Transport Canada AD CF-2019-16 requires 
revising Bell RFM BHT-429-FM-1 by incorporating revision 14, dated 
April 18, 2019.

Discussion of Final Airworthiness Directive

Comments

    The FAA received one comment from an individual who supported the 
NPRM without change.

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 
comment 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.

Related Service Information

    The FAA reviewed Section 2--Normal Procedures, Section 3--Emergency 
and Malfunction Procedures, and Section 4--Performance, of Bell RFM 
BHT-429-FM-1, Revision 14, dated April 18, 2019. This revision of the 
service information adds a procedure to reduce the risk of trim runaway 
during start sequence, cautions to reduce the risk of uncommanded 
control movement during engine start and takeoff and re-setting force 
trim detent instructions during engine start and takeoff, and an 
emergency procedure to assist flight crew to recognize trim runaway and 
response instructions.

Costs of Compliance

    The FAA estimates that this AD affects 120 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.
    Revising the existing RFM for your helicopter takes about 0.50 
work-hour for an estimated cost of $43 per helicopter and $5,160 for 
the U.S. fleet.

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 helicopters 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,

[[Page 49911]]

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:

2021-18-10 Bell Textron Canada Limited: Amendment 39-21711; Docket 
No. FAA-2021-0497; Project Identifier 2019-SW-043-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective October 12, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Bell Textron Canada Limited Model 429 
helicopters, certificated in any category, serial numbers 57001 and 
subsequent.

(d) Subject

    Joint Aircraft Service Component (JASC) Code: 6720, Tail Rotor 
Control System.

(e) Unsafe Condition

    This AD was prompted by three reports of unexpected forces or 
uncommanded inputs to the directional (yaw) control system. The FAA 
is issuing this AD to prevent yaw trim runaway. The unsafe 
condition, if not addressed, could result in loss of control of the 
helicopter.

(f) Compliance

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

(g) Required Actions

    (1) Within 30 days after the effective date of this AD, revise 
the existing Rotorcraft Flight Manual for your helicopter as 
follows:
    (i) In Section 2, Normal Procedures, under 2-4. INTERIOR AND 
PRESTART CHECK, add the following as item 25: ``25. Depress the 
cyclic force TRIM REL button and collective FORCE REL button (4-axis 
only) to center actuators and extinguish any active out of detent 
indications.''
    (ii) In Section 2, Normal Procedures, under 2-5. ENGINE START 
and under 2-8. TAKEOFF, add the following above item 1: ``CAUTION: 
WHEN MANIPULATING FLIGHT CONTROLS WITH FORCE TRIM SELECTED ON, DO 
NOT RELEASE AFFECTED FLIGHT CONTROL UNTIL THE OUT OF DETENT 
INDICATION EXTINGUISHES. THE FLIGHT CONTROLS MAY BE RESET BY 
DEPRESSING THE CYCLIC FORCE TRIM REL BUTTON AND COLLECTIVE FORCE REL 
BUTTON (4-AXIS ONLY) UNTIL THE OUT OF DETENT INDICATION 
EXTINGUISHES.''
    (iii) In Section 3, Emergency and Malfunction Procedures, under 
3-9. AUTOMATIC FLIGHT CONTROL SYSTEM, add the information in Figure 
1 to paragraph (g)(1)(iii) of this AD as item 3-9-D:
[GRAPHIC] [TIFF OMITTED] TR07SE21.000

    (iv) In Section 4, Performance, under 4-2. POWER ASSURANCE 
CHECK, add the following above the instructions for performing a 
power assurance check: ``CAUTION: WHEN MANIPULATING FLIGHT CONTROLS 
WITH FORCE TRIM SELECTED ON, DO NOT RELEASE AFFECTED FLIGHT CONTROL 
UNTIL THE OUT OF DETENT INDICATION EXTINGUISHES. THE FLIGHT CONTROLS 
MAY BE RESET BY DEPRESSING THE CYCLIC FORCE TRIM REL BUTTON AND 
COLLECTIVE FORCE REL BUTTON (4-AXIS ONLY) UNTIL THE OUT OF DETENT 
INDICATION EXTINGUISHES.''
    (2) Using a document with information identical to the 
information in paragraph (g)(1) of this AD is acceptable for 
compliance

[[Page 49912]]

with the actions required by paragraph (g)(1) of this AD.
    (3) The actions required by paragraphs (g)(1) and (2) of this AD 
may be performed by the owner/operator (pilot) holding at least a 
private pilot certificate and must be entered into the aircraft 
records showing compliance with this AD in accordance with Sec.  
43.9(a)(1) through (4) and Sec.  91.417(a)(2)(v). The record must be 
maintained as required by Sec.  91.417, Sec.  121.380, or Sec.  
135.439.

(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 Mitch Soth, 
Flight Test Engineer, Southwest Section, Flight Test Branch, 
Compliance & Airworthiness Division, FAA, 10101 Hillwood Pkwy., Fort 
Worth, TX 76177; telephone (817) 222-5110; email [email protected].
    (2) The subject of this AD is addressed in Transport Canada 
Emergency AD CF-2019-16, dated May 6, 2019. You may view the 
Transport Canada AD on the internet at https://www.regulations.gov 
in Docket No. FAA-2021-0497.

(j) Material Incorporated by Reference

    None.

    Issued on August 26, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-19049 Filed 9-3-21; 8:45 am]
BILLING CODE 4910-13-P

Sources. Section 1 is written by AircraftDirectives from the record below and is a reading aid only. Section 2 is the United States Government's own text, reproduced without edit.

Federal Register: https://www.federalregister.gov/documents/2021/09/07/2021-19049/airworthiness-directives-bell-textron-canada-limited-helicopters

Official PDF: https://www.govinfo.gov/content/pkg/FR-2021-09-07/pdf/2021-19049.pdf

FAA DRS record: https://drs.faa.gov/browse/excelExternalWindow/1CC9789B67F22D138625874900584391.0001

Packet generated 2026-08-18 08:51 UTC.

This packet is not an airworthiness determination and not legal or maintenance advice. AircraftDirectives reproduces official records and condenses their wording for easier reading. It does not decide, certify or imply whether any aircraft, engine, appliance or part is airworthy, compliant, affected by this directive, or eligible for return to service. No inspection, approval, or determination of any kind is performed or implied by this document.

Section 1 is a reading aid, not the rule. It is our own plain-language condensation, written to help a reader find the relevant directive quickly. It is NOT a substitute for the regulation, it may omit conditions, exceptions, compliance times, alternative methods of compliance (AMOCs) and applicability limits, and it has no legal force whatsoever. Only the official text governs. Where Section 1 and Section 2 differ in any respect, Section 2 - and the official source it was retrieved from - controls absolutely.

Responsibility remains with the owner/operator. Under 14 CFR §91.403 and §91.417 the owner or operator is responsible for maintaining airworthiness and for required records; under §39.7 no person may operate a product to which an airworthiness directive applies except in accordance with that directive. Determining applicability to a specific serial number and configuration, and performing or supervising any required action, is the responsibility of the owner/operator and appropriately certificated personnel.

Accuracy and currency. Section 2 was retrieved at the time stamped above and is reproduced without edit; Federal Register material is a work of the United States Government. Directives are amended, corrected and superseded over time, and this sheet is a snapshot, not a live record - it does not update after printing. Re-check the official sources before acting on it. This packet is provided without warranty of any kind, express or implied, including fitness for a particular purpose. We do not sell parts and have no commercial interest in any action a directive may require.

AircraftDirectives · AD 2021-18-10 · Section 1 is our plain-language reading aid; Section 2 is the official Federal Register text and controls where the two differ. Not an airworthiness determination — 14 CFR §91.403 / §91.417 responsibility remains with the owner/operator. Retrieved 2026-08-18 08:51 UTC.