DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-1078; Project Identifier MCAI-2020-01574-R;
Amendment 39-22014; AD 2022-08-11]
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 in-service reports of the loss of display and subsequent
recovery of certain display units (DUs). This AD requires revising the
existing rotorcraft flight manual supplement (RFMS) for your helicopter
and disabling the traffic alert and collision avoidance system (TCAS)
POP-UP feature for certain DUs. The FAA is issuing this AD to address
the unsafe condition on these products.

DATES: This AD is effective May 27, 2022.
The Director of the Federal Register approved the incorporation by
reference of a certain document listed in this AD as of May 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 productsupport@bellflight.com; 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. It is also available at https://www.regulations.gov by searching
for and locating Docket No. FAA-2021-1078.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-1078; 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: Darren Gassetto, Aerospace Engineer,
COS Program Management Section, FAA, Operational Safety Branch, 1600
Stewart Avenue, Suite 410, Westbury, NY 11590; telephone (516) 228-
7323; email Darren.Gassetto@faa.gov.

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 through 57369
inclusive, 57371, and 57373. The NPRM published in the Federal Register
on December 28, 2021 (86 FR 73708; corrected January 10, 2022 (87 FR
1083)). In the NPRM, the FAA proposed to require revising the existing
RFMS for your helicopter and disabling the TCAS POP-UP feature for
certain DUs. The NPRM was prompted by Transport Canada AD CF-2020-18R1,
dated November 27, 2020 (Transport Canada AD CF-2020-18R1), issued by
Transport Canada, which is the aviation authority for Canada, to
correct an unsafe condition for Bell Textron Canada Limited Model 429
helicopters, serial numbers 57001 through 57369, 57371, and 57373.
Transport Canada advises that it has received in-service reports of the
loss of display and subsequent recovery of the DU manufactured by
Rogerson Kratos (RK). During an instrument flight rules approach, a
Bell Textron Canada Limited Model 429 helicopter lost its center DU
display, which then rebooted, and subsequently lost its right-hand side
(RHS) DU display, which then also rebooted. Investigation revealed that
the DUs' power cycle occurred while in Map-Mode, which was caused by
the RK DUs' limited processing capability for excessive null waypoints
generated by the Garmin GTN 750/650 GPS/NAV/COMM/MFD.
Transport Canada also advises that the use of Map-Mode to the
center DU should be limited only for Bell Textron Canada Limited Model
429 helicopters equipped with RK DUs and Garmin GTN 750/650 main
software version 6.21 or later and that the use of Map-Mode should be
prohibited on both the RHS DU and left-hand side DU, if installed. In
addition, Transport Canada advises that a new emergency and malfunction
procedure in the event of center DU failure should be implemented. If
not addressed, a DU power cycle occurring during flight and consequent
momentary loss of display information on the primary flight display and
other DUs could result in the unexpected loss of display of important
flight parameters to the pilots, including attitude, approach,
airspeed, altitude, flight director information, navigation system
cues, as well as engine and rotor drive system indications.

Discussion of Final Airworthiness Directive

Comments

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

Request To Revise Figures 1 and 2 to Paragraph (g) To Match the RFMS

Bell Textron Canada Limited requested that the limitations
specified in figures 1 and 2 to paragraph (g) of the proposed AD be
revised to reflect the limitations identified in Bell Alert Service
Bulletin 429-20-51, Revision B, dated July 17, 2021; and Bell 429
Rotorcraft Flight Manual Supplement BHT-429-FMS-19, Revision 7, dated
December 14, 2021. The commenter noted that the unsafe condition
identified in the NPRM is only present when Garmin GTN 650/750 main
software version 6.21 or later is installed because these software
versions introduce an increased number of waypoints that can be
displayed, which is beyond the memory capability of the RK DU. In
addition, the commenter explained that the Garmin main software version
is obvious to the pilot because it is displayed on the GTN 650/750
``splash''screen when the DUs are powered-up and can be easily accessed
prior to flight through the GTN 650/750 configuration pages.
The FAA partially agrees with the commenter's request. The FAA
agrees with revising the limitations specified in figures 1 and 2 to
paragraph (g) of this AD to reflect the Garmin GTN 650/750 main
software versions specified in Bell 429 Rotorcraft Flight Manual
Supplement BHT-429-FMS-19, Revision 7, dated December 14, 2021, because
the unsafe condition is limited to Garmin GTN 650/750 main software
version 6.21 or later, and the flight crew can determine the software
version from the DUs and not from memory or running a diagnostic
program. The FAA has revised figures 1 and 2 to paragraph (g) of this
AD accordingly. The FAA notes that Bell Alert Service Bulletin
429-20-51, Revision B, dated July 17, 2021, refers to an older revision
of the Bell 429 Rotorcraft Flight Manual Supplement BHT-429-FMS-19,
which does not include all of the clarifying information regarding the
affected manufacturer and software versions.

Request To Revise Figure 3 to Paragraph (g) To Specify the RK DU
Configuration

Bell Textron Canada Limited requested that figure 3 to paragraph
(g) of the proposed AD be revised to specify that the revision to the
Emergency and Malfunction Procedures (section 3) of the existing RFMS
applies to a center DU with the RK DU configuration. The commenter
explained that Bell 429 Rotorcraft Flight Manual Supplement BHT-429-
FMS-19, Revision 7, dated December 14, 2021, included a revision to
Section 3-14-B., CENTER DU FAILURE, to clarify that the Emergency and
Malfunction Procedure applied only to the RK DU configuration.
The FAA agrees with the commenter's request and has revised
paragraph (g) of this AD and figure 3 to paragraph (g) of this AD to
specify that the Emergency and Malfunction Procedures apply to a center
DU with the RK DU configuration. The FAA contacted Transport Canada,
the State of Design Authority for Bell Textron Canada Limited Model 429
helicopters, and confirmed that the Emergency and Malfunction
Procedures are applicable only to a center DU with the RK DU
configuration.

Request To Revise Note 1 to Paragraph (g) To Refer to a Later Revision
of the RFMS

Bell Textron Canada Limited requested that Note 1 to paragraph (g)
be revised to refer to only Bell 429 Rotorcraft Flight Manual
Supplement BHT-429-FMS-19, Revision 7, dated December 14, 2021. The
commenter explained that this revision level provides additional
clarifying information regarding the manufacturer and software versions
affected by the unsafe condition identified in the NPRM.
The FAA agrees with the commenter's request for the reason provided
by the commenter and because the FAA has additionally agreed to certain
changes in the information presented in figures 1, 2, and 3 to
paragraph (g) of this AD in response to the commenter's previous
comments regarding the RFMS revision. In the proposed AD Note 1 to
paragraph (g) was as follows: ``Note 1 to paragraph (g): The
information in the '`CENTER DU FAILURE' specified in figure 3 to
paragraph (g) of this AD can be found in Bell 429 Rotorcraft Flight
Manual Supplement BHT-429-FMS-19, Revisions 3, 4, 5, and 6.'' In this
AD the FAA revised Note 1 to paragraph (g) to refer to Bell 429
Rotorcraft Flight Manual Supplement BHT-429-FMS-19, Revision 7, dated
December 14, 2021, and to include the pertinent changes that resulted
from the other Bell Textron Canada Limited comments previously
discussed.

Changes Since the NPRM Was Issued

After the NPRM was issued, Transport Canada issued Transport Canada
AD CF-2020-18R2, dated January 27, 2022 (Transport Canada AD CF-2020-
18R2), which superseded Transport Canada AD CF-2020-18R1. Transport
Canada AD CF-2020-18R2, mandates incorporation of Bell 429 Rotorcraft
Flight Manual Supplement BHT-429-FMS-19, Revision 7, dated December 14,
2021, which specifies disabling the TCAS POP-UP feature for certain
DUs. That action was included in the proposed AD requirements, and in
the NPRM preamble, was identified in the Differences Between this
Proposed AD and the Transport Canada AD section because it was not
included in Transport Canada AD CF-2020-18R1 but was included in the
proposed AD requirements. That difference has been removed from this
final rule.

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, except for the changes
described previously, air safety requires adopting this AD as proposed.
Accordingly, the FAA is issuing this AD to address the unsafe condition
on these helicopters. 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 Bell Alert Service Bulletin 429-20-51, Revision B,
dated July 17, 2021, which specifies procedures for disabling the TCAS
POP-UP feature for certain DUs. 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.

Differences Between This AD and the Transport Canada AD

Transport Canada AD CF-2020-18R2 requires operators to ``advise all
flight crews'' of the changes introduced by the RFMS revision. However,
this AD does not specifically require that action. 14 CFR 91.9 requires
that no person may operate a civil aircraft without complying with the
operating limitations specified in the RFMS. Therefore, including a
requirement in this AD to operate the helicopter according to the
revised RFMS would be redundant and unnecessary. Further, compliance
with such a requirement in an AD would be impracticable to demonstrate
or track on an ongoing basis; therefore, a requirement to operate the
helicopter in such a manner would be unenforceable. The flight manual
supplement changes in this AD also apply to the emergency and
malfunction procedures section of the existing RFMS for your
helicopter. FAA regulations mandate compliance only with the operating
limitations section of the flight manual. Nonetheless, the FAA
recommends that flight crews of the helicopters listed in the
applicability operate in accordance with the revised emergency and
malfunction procedures specified in this AD.

Costs of Compliance

The FAA estimates that this AD affects 88 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 RFMS for your helicopter takes about 1 work-
hour for an estimated cost of $85 per helicopter and $7,480 for the
U.S. fleet.
Disabling the TCAS POP-UP feature for your helicopter takes about
0.5 work-hours for an estimated cost of $43 per helicopter and $3,784
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 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

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: