[Federal Register Volume 87, Number 242 (Monday, December 19, 2022)]
[Rules and Regulations]
[Pages 77485-77487]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-27397]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0993; Project Identifier MCAI-2022-00295-T; 
Amendment 39-22262; AD 2022-25-06]
RIN 2120-AA64


Airworthiness Directives; De Havilland Aircraft of Canada Limited 
(Type Certificate Previously Held by Bombardier, Inc.) Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain De Havilland Aircraft of Canada Limited Model DHC-8-402 
airplanes. This AD was prompted by an investigation that found that the 
actual operating temperatures within the integrated flight cabinet 
(IFC) were significantly higher than anticipated during certification. 
This AD requires a modification to improve the IFC cooling capacity. 
The FAA is issuing this AD to address the unsafe condition on these 
products.

DATES: This AD is effective January 23, 2023.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of January 23, 
2023.

ADDRESSES: 
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2022-0993; 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 mandatory continuing airworthiness 
information (MCAI), any comments received, and other information. The 
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.
    Material Incorporated by Reference:
     For service information identified in this final rule, 
contact De Havilland Aircraft of Canada Limited, Dash 8 Series Customer 
Response Centre, 5800 Explorer Drive, Mississauga, Ontario, L4W 5K9, 
Canada; telephone North America (toll-free): 855-310-1013, Direct: 647-
277-5820; email dehavilland.com">thd@dehavilland.com; website dehavilland.com.
     You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 South 
216th St., Des Moines, WA. For information on the availability of this 
material at the FAA, call 206-231-3195. It is also available at 
regulations.gov under Docket No. FAA-2022-0993.

FOR FURTHER INFORMATION CONTACT: Gabriel Kim, Aerospace Engineer, 
Mechanical Systems and Administrative Services Section, FAA, New York 
ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
telephone 516-228-7300; 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 certain De Havilland 
Aircraft of Canada Limited Model DHC-8-402 airplanes. The NPRM 
published in the Federal Register on August 12, 2022 (87 FR 49776). The 
NPRM was prompted by AD CF-2022-09, dated March 3, 2022, issued by 
Transport Canada, which is the aviation authority for Canada (referred 
to after this as the MCAI) (Transport Canada CF-2022-09). The MCAI 
states that as a result of higher-than-expected failure rates in 
service, the supplier's investigation found that actual operating 
temperatures within the IFC were significantly higher than anticipated 
during certification. Consequently, the reliability of the IFC module 
does not meet safety objectives. The MCAI further states this failure 
mode could lead to uncontrolled autopilot pitch trim servo runaway and/
or failure of the stall warning and stick pusher, resulting in reduced 
controllability of the airplane.
    In the NPRM, the FAA proposed to require a modification to improve 
the IFC cooling capacity. The FAA is issuing this AD to address the 
unsafe condition on these products.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2022-0993.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from the Air Line Pilots Association, 
International (ALPA), who supported the NPRM without change.
    The FAA received an additional comment from Horizon Air. The 
following presents the comment received on the NPRM and the FAA's 
response to each comment.

Request To Exclude Job Set-Up and Close-Out

    Horizon Air requested that the final rule mandate only paragraph 
3.B., ``Procedure,'' of the Accomplishment Instructions of De Havilland 
Service Bulletin 84-21-24, Revision B, dated Oct 13, 2021, because that 
corrects the unsafe condition. Horizon Air stated that paragraph 3.A. 
``Job Set-up,'' and paragraph 3.C., ``Close Out'' of the Accomplishment 
Instructions of De Havilland Service Bulletin 84-21-24, Revision B, 
dated Oct 13, 2021, do not directly correct the unsafe condition. The 
commenter stated that incorporating the ``Job Set-up'' and ``Close 
Out'' procedures as a requirement of the AD restricts an operator's 
ability to perform other maintenance in conjunction with the 
incorporation of the service information.
    The FAA agrees with the requested change for the reasons provided 
by the commenter. In addition, this change corresponds to Transport 
Canada AD CF-2022-09, dated March 3, 2022. The FAA has revised 
paragraph (g) of this AD accordingly.

Conclusion

    This product has been approved by the aviation authority of another

[[Page 77486]]

country and is approved for operation in the United States. Pursuant to 
the FAA's bilateral agreement with this State of Design Authority, it 
has notified the FAA of the unsafe condition described in the MCAI 
referenced above. 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 this product. 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

    De Havilland Aircraft of Canada Limited has issued Service Bulletin 
84-21-24, Revision B, dated October 13, 2021. This service information 
specifies procedures for a modification to improve the IFC cooling 
capacity. The tasks include reworking the forward and aft avionics rack 
side panels, removing the piccolo tube assemblies, doing a general 
visual inspection for contamination of the IFCs and avionics rack, 
cleaning any contamination found, installing and routing new cooling 
ducts, and installing two new extraction plenums in the avionics rack 
cooling system.
    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.

Costs of Compliance

    The FAA estimates that this AD affects 56 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                      Estimated Costs for Required Actions
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                                                                                    Cost per       Cost on U.S.
                          Labor cost                              Parts cost        product         operators
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11 work-hours x $85 per hour = $935..........................          $6,950           $7,885         $441,560
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    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some or all of the costs of 
this AD may be covered under warranty, thereby reducing the cost impact 
on affected operators.

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:

2022-25-06 De Havilland Aircraft of Canada Limited (Type Certificate 
Previously Held by Bombardier, Inc.): Amendment 39-22262; Docket No. 
FAA-2022-0993; Project Identifier MCAI-2022-00295-T

(a) Effective Date

    This airworthiness directive (AD) is effective January 23, 2023.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to De Havilland Aircraft of Canada Limited (Type 
Certificate previously held by Bombardier Inc.) Model DHC-8-402 
airplanes, certificated in any category, serial numbers 4095 through 
4633 inclusive.

(d) Subject

    Air Transport Association (ATA) of America Code 21, Air 
Conditioning System.

(e) Unsafe Condition

    This AD was prompted by an investigation that found that the 
actual operating temperatures within the integrated flight cabinet 
(IFC) were significantly higher than anticipated during the 
certification. Consequently, the reliability of the IFC module does 
not meet safety objectives. The FAA is issuing this AD to address 
the high operating temperatures within the IFC, which could lead to 
uncontrolled autopilot pitch trim servo runaway and failure of the 
stall warning and stick pusher, resulting in reduced controllability 
of the airplane.

(f) Compliance

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

(g) Required Actions

    Within 8,000 flight hours or 48 months, whichever occurs first, 
from the effective date of this AD, do a modification to improve the 
IFC cooling capacity, in accordance with paragraph 3.B., 
``Procedure,'' of the Accomplishment Instructions of De Havilland 
Aircraft of Canada Limited Service Bulletin 84-21-24, Revision B, 
dated Oct 13, 2021.

(h) Credit for Previous Actions

    This paragraph provides credit for actions required by paragraph 
(g) of this AD, if those actions were performed before the effective 
date of this AD using De Havilland Aircraft

[[Page 77487]]

of Canada Limited Service Bulletin 84-21-24, Revision A, dated 
August 20, 2021.

(i) Other FAA AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, New 
York 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 ATTN: Program Manager, Continuing Operational 
Safety, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; telephone 516-228-7300; fax 516-794-5531. Before 
using any approved AMOC, notify your appropriate principal 
inspector, or lacking a principal inspector, the manager of the 
responsible Flight Standards Office.
    (2) Contacting the Manufacturer: For any requirement in this AD 
to obtain instructions from a manufacturer, the instructions must be 
accomplished using a method approved by the Manager, New York ACO 
Branch, FAA; or Transport Canada; or De Havilland Aircraft of Canada 
Limited's Transport Canada Design Approval Organization (DAO). If 
approved by the DAO, the approval must include the DAO-authorized 
signature.

(j) Additional Information

    (1) Refer to Transport Canada AD CF-2022-09, dated March 3, 
2022, for related information. This Transport Canada AD may be found 
in the AD docket at regulations.gov under Docket No. FAA-2022-0993.
    (2) For more information about this AD, contact Gabriel Kim, 
Aerospace Engineer, Mechanical Systems and Administrative Services 
Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; telephone 516-228-7300; email [email protected].
    (3) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (k)(3) and (4) of this AD.

(k) 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 this AD specifies otherwise.
    (i) De Havilland Aircraft of Canada Limited Service Bulletin 84-
21-24, Revision B, dated Oct 13, 2021.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact De 
Havilland Aircraft of Canada Limited, Dash 8 Series Customer 
Response Centre, 5800 Explorer Drive, Mississauga, Ontario, L4W 5K9, 
Canada; telephone North America (toll-free): 855-310-1013, Direct: 
647-277-5820; email dehavilland.com">thd@dehavilland.com; website dehavilland.com.
    (4) You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA. For information on the availability 
of this material at the FAA, call 206-231-3195.
    (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: www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on November 30, 2022.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2022-27397 Filed 12-16-22; 8:45 am]
BILLING CODE 4910-13-P