DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-1466; Project Identifier MCAI-2024-00205-R;
Amendment 39-22752; AD 2024-07-51]
RIN 2120-AA64

Airworthiness Directives; Bell Textron Canada Limited Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Bell Textron Canada Limited Model 429 helicopters. The FAA
previously sent this AD as an emergency AD to all known U.S. owners and
operators of these helicopters. This AD was prompted by multiple
reports of tail rotor (T/R) blade abrasion strip cracks. This AD
requires repetitively inspecting and checking the T/R blade abrasion
strip on certain T/R blades and, depending on results, replacing or
marking the T/R blade. This AD also prohibits installing affected T/R
blades on any helicopter. The FAA is issuing this AD to address the
unsafe condition on these products.

DATES: This AD is effective June 10, 2024. Emergency AD 2024-07-51,
issued on March 29, 2024, which contained the requirements of this
amendment, was effective with actual notice.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of June 10,
2024.
The FAA must receive comments on this AD by July 8, 2024.

ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
Federal eRulemaking Portal: Go to regulations.gov. Follow
the instructions for submitting comments.
Fax: (202) 493-2251.
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.
Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2024-1466; 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 Docket Operations is listed above.
Material Incorporated by Reference:
For Bell material, contact Bell Textron Canada Limited,
12,800 Rue de l'Avenir, Mirabel, Quebec J7J 1R4, Canada; phone 1-450-
437-2862 or 1-800-363-8023; fax 1-450-433-0272; email
productsupport@bellflight.com; or at bellflight.com/support/contact-support.
You may view this material 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. It is also available at
regulations.gov under Docket No. FAA-2024-1466.

FOR FURTHER INFORMATION CONTACT: Dan McCully, Aviation Safety Engineer,
FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone (404)
474-5548; email william.mccully@faa.gov.

SUPPLEMENTARY INFORMATION:

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-2024-1466; Project Identifier MCAI-
2024-00205-R'' 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
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 Dan
McCully, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; phone (404) 474-5548; email
william.mccully@faa.gov. Any commentary that the FAA receives that is
not specifically designated as CBI will be placed in the public docket
for this rulemaking.

Background

The FAA issued Emergency AD 2024-07-51, dated March 29, 2024 (the
emergency AD), to address an unsafe condition on Bell Textron Canada
Limited Model 429 helicopters, serial number 57001 and subsequent, with
a T/R blade part number (P/N) 429-016-101-105 having a serial number
identified in Table 1 of Bell Alert Service Bulletin 429-24-63, dated
March 21, 2024 (ASB 429-24-63) installed. The FAA sent the emergency AD
to all known U.S. owners and operators of these helicopters. For
affected T/R blades with an abrasion strip with any coating (such as a
protective tape or protective coating), the emergency AD requires
accomplishing actions in accordance with a method approved by the FAA,
Transport Canada, or Bell Textron Canada Ltd.'s Design Approval
Organization. For all other affected T/R blades, the emergency AD
requires repetitively cleaning and inspecting, and repetitively
checking the T/R blade abrasion strip and, depending on results,
replacing, marking, or remarking the T/R blade. The emergency AD also
prohibits installing affected T/R blades on any helicopter.
The emergency AD was prompted by Transport Canada Emergency AD CF-
2024-11, dated March 22, 2024 (Transport Canada AD CF-2024-11), issued
by Transport Canada, which is the aviation authority for Canada, to
correct an unsafe condition on certain serial-numbered Bell Textron
Canada Limited Model 429 helicopters. Transport Canada states that an
investigation revealed a manufacturing defect in certain serial-
numbered T/R blades part number 429-016-101-105. Transport Canada
further states that a critical step in the fabrication of the abrasion
strip was missed, which could result in the presence of stress risers,
leading to fatigue cracking. Accordingly, Transport Canada AD CF-2024-
11 requires inspecting the T/R blade abrasion strips and, depending on
the results, replacing or marking the T/R blade. Thereafter, Transport
Canada AD CF-2024-11 requires repetitively checking the T/R blade
abrasion strips and, depending on the results, replacing the T/R blade.
Lastly, Transport Canada AD CF-2024-11 requires repetitively inspecting
the T/R blade abrasion strips and, depending on the results, replacing
the T/R blade or reapplying the marking. The FAA is issuing this AD to
address the unsafe condition on these products.
You may examine Transport Canada AD CF-2024-11 in the AD docket at
regulations.gov under Docket No. FAA-2024-1466.

Related Material Under 1 CFR Part 51

The FAA reviewed ASB 429-24-63. For certain serial-numbered T/R
blades P/N 429-016-101-105, this material specifies procedures for
cleaning the T/R blade abrasion strip and, using a bright light,
visually inspecting each side of the T/R blade abrasion strip for a
chordwise crack. If there is a crack, this material specifies
procedures for replacing the T/R blade. If there is not a crack, this
material specifies procedures for marking the T/R blade with a paint
marker. Following application of the marking, this material specifies
procedures for visually checking each side of the T/R blade abrasion
strip for a chordwise crack before each engine start and a longer-term
repetitive visual inspection of the T/R blade abrasion strip for a
chordwise crack and if necessary, reapplying the marking. If a crack is
found as a result of any check or longer-term visual inspection, this
material specifies procedures for replacing the T/R blade.
This material 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.

FAA's Determination

These helicopters have been approved by the aviation authority of
another country and are approved for operation in the United States.
Pursuant to the FAA's bilateral agreement with the State of Design
Authority, it has notified the FAA of the unsafe condition described in
its emergency AD and the material described above. The FAA is issuing
this AD after determining that the unsafe condition described
previously is likely to exist or develop on other products of the same
type design.

AD Requirements

This AD requires accomplishing the actions specified in Transport
Canada AD CF-2024-11, except as discussed under ``Differences Between
this AD and the Transport Canada Emergency AD.''
This AD requires a check that the owner/operator (pilot) holding at
least a private pilot certificate may perform and must enter compliance
with the applicable paragraph of the AD into the helicopter maintenance
records in accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The
pilot may perform this check because it only involves using a
flashlight and visually checking affected T/R blade abrasion strips for
a crack. This action could be performed equally well by a pilot or a
mechanic. This is an exception to the FAA's standard maintenance
regulations.

Differences Between This AD and the Transport Canada Emergency AD

Regarding the initial inspection for a chordwise crack, this AD
distinguishes requirements if there is or is not any coating (such as a
protective tape or protective coating) over the T/R blade abrasion
strip, whereas Transport Canada AD CF-2024-11 does not. This AD
requires reporting certain information if any T/R blade abrasion strip
has a crack, whereas Transport Canada AD CF-2024-11 does not. Transport
Canada AD CF-2024-11 allows the installation of an affected T/R blade
so long as it passes the inspection and is marked as required within,
whereas this AD prohibits installing an affected T/R blade on any
helicopter.

Interim Action

The FAA considers this AD interim action. If final action is later
identified, the FAA might consider further rulemaking then.

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.
An unsafe condition exists that required the immediate adoption of
Emergency AD 2024-07-51, issued on March 29, 2024, to all known U.S.
owners and operators of these helicopters. The FAA found that the risk
to the flying public justified waiving notice and comment prior to
adoption of this rule because the affected components are part of an
assembly that is critical to the control of a helicopter. Multiple T/R
abrasion strip cracks have been reported, and investigation revealed
that a manufacturing defect exists in some of the abrasion strips,
which may lead to fatigue cracking and catastrophic T/R blade failure,
which in turn can cause the destruction of the T/R gearbox and loss of
directional control. At this time, the growth rate of the fatigue
cracking has not been determined. For these reasons, the initial
actions required by this AD must be accomplished within three days or
prior to the second flight after the effective date of this AD,
whichever occurs first. Thereafter, other actions required by this AD
must be accomplished before the second and each subsequent flight.
These conditions still exist, therefore, notice and opportunity for
prior public comment are impracticable and contrary to the public
interest pursuant to 5 U.S.C. 553(b)(3)(B).
In addition, 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,
for the same reasons the FAA found good cause to forego notice and
comment.

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 prior notice and
comment, RFA analysis is not required.

Costs of Compliance

The FAA estimates that this AD affects 145 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.
Actions required for a T/R blade abrasion strip with any coating
could vary. The FAA has no data to determine the costs to accomplish
these actions or the number of helicopters that may be affected by this
requirement.
Cleaning and inspecting a T/R blade abrasion strip takes
approximately 0.5 work-hour for an estimated cost of up to $170 per
helicopter (there are up to 4 affected T/R blades per helicopter) and
$24,650 for the U.S. fleet, per inspection cycle. Checking a T/R blade
abrasion strip takes approximately 0.25 work-hour for an estimated cost
of up to $85 per helicopter and $12,325 for the U.S. fleet, per check
cycle. Marking a T/R blade takes approximately 0.25 work-hour with a
nominal parts cost for an estimated cost of up to $85 per helicopter
and $12,325 for the U.S. fleet for the initial application and per
reapplication.
If required, replacing a T/R blade takes approximately 6 work-hours
and parts cost approximately $53,802 for an estimated cost of $54,312
per T/R blade. Reporting information takes approximately 1 work-hour
for an estimated cost of $85 per T/R blade.

Paperwork Reduction Act

A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a currently valid OMB Control Number. The OMB
Control Number for this information collection is 2120-0056. Public
reporting for this collection of information is estimated to be
approximately 1 hour per response, including the time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the
collection of information. All responses to this collection of
information are mandatory. Send comments regarding this burden estimate
or any other aspect of this collection of information, including
suggestions for reducing this burden, to: Information Collection
Clearance Officer, Federal Aviation Administration, 10101 Hillwood
Parkway, Fort Worth, TX 76177-1524.

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, 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.

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

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]

2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive: