Published 2021-12-01 · Federal Register document 2021-26109
Airworthiness Directives; De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes
Publication summary
The FAA is adopting a new airworthiness directive (AD) for certain De Havilland Aircraft of Canada Limited Model DHC-8-401 and - 402 airplanes. This AD was prompted by reports of loss of hydraulic fluid and annunciation of the check fire detect light. This AD requires doing a detailed visual inspection for chafing and proper clearance of the left-hand (LH) and right-hand (RH) main landing gear (MLG) primary zone advanced pneumatic detector (APD) sensing lines, the hydraulic tube assemblies, and the surrounding structure, and doing all applicable corrective action. The FAA is issuing this AD to address the unsafe condition on these products.
Why this record is shown
Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:24:08.106391+00:00. The title, summary and date are source facts.
- Source revision
- federal_register_ad_metadata_2021-9c919420683447c6
- Source row
- results[426]
- Raw source SHA-256
- 9c919420683447c683ad0c877cb886e341c11862be32b47c536a001b1d76dcb5
Final-rule publication
Recorded publication clauses
- AD identifier printed in this edition
- 2021-23-02
- Effective date printed in this edition
- 2022-01-05
Read 11 complete recorded clauses
Effective Date
(a) Effective Date
This airworthiness directive (AD) is effective January 5, 2022.
Exact source excerpt. Text positions 10093–10182, end exclusive, in the original decoded publication. SHA-256: c1610321fbcf9bca1959e57359d21d268246aff6fe54164043b5d15d0efd9086
Affected ADs
(b) Affected ADs
None.
Exact source excerpt. Text positions 10182–10211, end exclusive, in the original decoded publication. SHA-256: 871a4afc60ceeae06e8010585055188633d616078500c45937092bfe892239c0
Applicability wording · Applicability
(c) Applicability
This AD applies to De Havilland Aircraft of Canada Limited Model
DHC-8-401 and -402 airplanes, certificated in any category, serial
numbers 4001 and 4003 through 4614 inclusive.
Exact source excerpt. Text positions 10211–10415, end exclusive, in the original decoded publication. SHA-256: fc959728459ccbf2c2480bdd68143228c6aa9bc3afc99ed658e01cf25f7281e7
Subject
(d) Subject
Air Transport Association (ATA) of America Code 26, Fire
protection.
Exact source excerpt. Text positions 10415–10503, end exclusive, in the original decoded publication. SHA-256: d2a9cf8a8912242590075a047b779e20ffaf976cb7811f4525197162c9aaae16
Unsafe Condition
(e) Unsafe Condition
This AD was prompted by reports of loss of hydraulic fluid and
annunciation of the check fire detect light. The FAA is issuing this
AD to address insufficient separation between the advanced pneumatic
detector (APD) sensing line and surrounding components, which could
lead to a hydraulic leak, loss of hydraulic systems and loss of fire
detection in the main landing gear (MLG) primary zone should
prolonged contact occur.
Exact source excerpt. Text positions 10503–10960, end exclusive, in the original decoded publication. SHA-256: 4726064567a3f23c6b3837277fac5223d7cd136421aad4dd667c0a131e1c3204
Compliance
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
Exact source excerpt. Text positions 10960–11062, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3
Inspection and Corrective Actions
(g) Inspection and Corrective Actions
Within 48 months or 8,000 flight hours, whichever occurs first
after the effective date of this AD: Do a detailed visual inspection
for chafing and proper clearance of the left- and right-hand MLG
primary zone APD sensing lines, the hydraulic tube assemblies and
the surrounding structure, and do all applicable corrective actions,
in accordance with paragraph 3.B. of the Accomplishment Instructions
of De Havilland Aircraft of Canada Limited Service Bulletin 84-26-
20, Revision A, dated March 9, 2021. Do all applicable corrective
actions before further flight.
Exact source excerpt. Text positions 11062–11678, end exclusive, in the original decoded publication. SHA-256: b1bd4aa406ff83472d7db985a75a070b4d1dc5cc3a877edd2544a2ed33d4a30c
Credit for Previous Actions
(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 of Canada Limited
Service Bulletin 84-26-20, dated October 21, 2020.
Exact source excerpt. Text positions 11678–11966, end exclusive, in the original decoded publication. SHA-256: 33dbadfd8e9fbdc5346e6dec36d0bcb3ebbf69524798e2fd27baa3b554e398c2
Other FAA AD Provisions
(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
[[Page 68109]]
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 Civil Aviation (TCCA); or De
Havilland Aircraft of Canada Limited's TCCA Design Approval
Organization (DAO). If approved by the DAO, the approval must
include the DAO-authorized signature.
Exact source excerpt. Text positions 11966–13264, end exclusive, in the original decoded publication. SHA-256: aa6e699aa184f6fd8c420487126d5ff0ee45ae3d809cf23210280a1ba95612c2
Related Information
(j) Related Information
(1) Refer to Mandatory Continuing Airworthiness Information
(MCAI) TCCA AD CF-2021-12, dated April 14, 2021, for related
information. This MCAI may be found in the AD docket on the internet
at https://www.regulations.gov by searching for and locating Docket
No. FAA-2021-0656.
(2) For more information about this AD, contact Chirayu Gupta,
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; fax 516-794-5531; 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.
Exact source excerpt. Text positions 13264–14038, end exclusive, in the original decoded publication. SHA-256: de552f74e77970fb2e2f80e706d9785702c7460c835c0f413cf75cc47541679a
Material Incorporated by Reference
(k) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference (IBR) 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-
26-20, Revision A, dated March 9, 2021.
(ii) [Reserved]
(3) For service information identified in this AD, contact De
Havilland Aircraft of Canada Limited, Q-Series Technical Help Desk,
123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone
416-375-4000; fax 416-375-4539; email [email protected]; internet
https://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: https://www.archives.gov/federal-register/cfr/ibr-locations.html.
Exact source excerpt. Text positions 14038–15374, end exclusive, in the original decoded publication. SHA-256: 12d2ccf6b8a8b381b45b54d438aee6a9ed75a614e95533b7e1f1bae40b4cb4b4
No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.
Find all recorded historical references to AD 2021-23-02 · 0 printed reference observations in this pinned collection.
These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.
Why these observations are shown
They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.
Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 335ebf7477789fcc6e0367d59e38c626ecba32b1c459036a7e3199f55481083c. Source manifest: 47427bbe3c3d82f717442b37256495bc43c1c779e107d62c14cfac09f2d66c60.
Official source · 2021-12-01
Publication text
This is the complete recorded text of this dated publication.
Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.
Read the complete official publication text
[Federal Register Volume 86, Number 228 (Wednesday, December 1, 2021)]
[Rules and Regulations]
[Pages 68107-68109]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-26109]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2021-0656; Project Identifier MCAI-2021-00394-T;
Amendment 39-21800; AD 2021-23-02]
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.
-----------------------------------------------------------------------
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain De Havilland Aircraft of Canada Limited Model DHC-8-401 and -
402 airplanes. This AD was prompted by reports of loss of hydraulic
fluid and annunciation of the check fire detect light. This AD requires
doing a detailed visual inspection for chafing and proper clearance of
the left-hand (LH) and right-hand (RH) main landing gear (MLG) primary
zone advanced pneumatic detector (APD) sensing lines, the hydraulic
tube assemblies, and the surrounding structure, and doing all
applicable corrective action. The FAA is issuing this AD to address the
unsafe condition on these products.
DATES: This AD is effective January 5, 2022.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of January 5,
2022.
ADDRESSES: For service information identified in this final rule,
contact De Havilland Aircraft of Canada Limited, Q-Series Technical
Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada;
telephone 416-375-4000; fax 416-375-4539; email [email protected];
internet https://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 on the internet at https://www.regulations.gov by searching
for and locating Docket No. FAA-2021-0656.
Examining the AD Docket
You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
0656; 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
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: Chirayu Gupta, 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; fax 516-794-5531; email [email protected].
SUPPLEMENTARY INFORMATION:
Background
Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued TCCA AD CF-2021-12, dated April 14,
2021 (also referred to as the Mandatory Continuing Airworthiness
Information, or the MCAI), to correct an unsafe condition for certain
De Havilland Aircraft of Canada Limited Model DHC-8-401 and -402
airplanes. You may examine the MCAI in the AD docket on the internet at
https://www.regulations.gov by searching for and locating Docket No.
FAA-2021-0656.
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-8-401 and -402 airplanes. The NPRM
published in the Federal Register on August 12, 2021 (86 FR 44324). The
NPRM was prompted by reports of loss of hydraulic fluid and
annunciation of the check fire detect light. The NPRM proposed to
require doing a detailed visual inspection for chafing and proper
clearance of the LH and RH MLG primary zone APD sensing lines, the
hydraulic tube assemblies, and the surrounding structure, and doing all
applicable corrective actions. The FAA is issuing this AD to address
insufficient separation between the APD sensing line and surrounding
components, which could lead to a hydraulic leak, loss of hydraulic
systems, and loss of fire detection in the MLG primary zone should
prolonged contact occur. See the MCAI for additional background
information.
Comments
The FAA gave the public the opportunity to participate in
developing this final rule. The FAA has considered the comment
received. The Air Line Pilots Association, International (ALPA) stated
that it supports the NPRM.
Conclusion
The FAA reviewed the relevant data, considered the comment
received, and determined that air safety and the public interest
require adopting this final rule as proposed, except for minor
editorial changes. The FAA has determined that these minor changes:
<bullet> Are consistent with the intent that was proposed in the
NPRM for addressing the unsafe condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM.
Related Service Information Under 1 CFR Part 51
De Havilland Aircraft of Canada Limited has issued Service Bulletin
84-26-20, Revision A, dated March 9, 2021. This service information
describes procedures for doing a detailed visual inspection for chafing
and proper clearance of the LH and RH MLG primary zone APD sensing
lines, the hydraulic tube assemblies and the surrounding structure, and
doing all applicable corrective actions. Corrective actions include
repair and replacement of the APD sensing line and the hydraulic tube
assembly.
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 54 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
[[Page 68108]]
Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Labor cost Parts cost product operators
----------------------------------------------------------------------------------------------------------------
5 work-hours x $85 per hour = $425........................... $0 $425 $22,950
----------------------------------------------------------------------------------------------------------------
The FAA estimates the following costs to do any necessary on-
condition actions that would be required based on the results of any
required actions. The FAA has no way of determining the number of
aircraft that might need these on-condition actions:
Estimated Costs of On-Condition Actions
------------------------------------------------------------------------
Labor cost Parts cost Cost per product
------------------------------------------------------------------------
Up to 7 work-hours x $85 per Up to $12,643..... Up to $13,238.
hour = Up to $595.
------------------------------------------------------------------------
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.
Adoption of 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:
2021-23-02 De Havilland Aircraft of Canada Limited (Type Certificate
Previously Held by Bombardier, Inc.): Amendment 39-21800; Docket No.
FAA-2021-0656; Project Identifier MCAI-2021-00394-T.
(a) Effective Date
This airworthiness directive (AD) is effective January 5, 2022.
(b) Affected ADs
None.
(c) Applicability
This AD applies to De Havilland Aircraft of Canada Limited Model
DHC-8-401 and -402 airplanes, certificated in any category, serial
numbers 4001 and 4003 through 4614 inclusive.
(d) Subject
Air Transport Association (ATA) of America Code 26, Fire
protection.
(e) Unsafe Condition
This AD was prompted by reports of loss of hydraulic fluid and
annunciation of the check fire detect light. The FAA is issuing this
AD to address insufficient separation between the advanced pneumatic
detector (APD) sensing line and surrounding components, which could
lead to a hydraulic leak, loss of hydraulic systems and loss of fire
detection in the main landing gear (MLG) primary zone should
prolonged contact occur.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Inspection and Corrective Actions
Within 48 months or 8,000 flight hours, whichever occurs first
after the effective date of this AD: Do a detailed visual inspection
for chafing and proper clearance of the left- and right-hand MLG
primary zone APD sensing lines, the hydraulic tube assemblies and
the surrounding structure, and do all applicable corrective actions,
in accordance with paragraph 3.B. of the Accomplishment Instructions
of De Havilland Aircraft of Canada Limited Service Bulletin 84-26-
20, Revision A, dated March 9, 2021. Do all applicable corrective
actions before further flight.
(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 of Canada Limited
Service Bulletin 84-26-20, dated October 21, 2020.
(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
[[Page 68109]]
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 Civil Aviation (TCCA); or De
Havilland Aircraft of Canada Limited's TCCA Design Approval
Organization (DAO). If approved by the DAO, the approval must
include the DAO-authorized signature.
(j) Related Information
(1) Refer to Mandatory Continuing Airworthiness Information
(MCAI) TCCA AD CF-2021-12, dated April 14, 2021, for related
information. This MCAI may be found in the AD docket on the internet
at https://www.regulations.gov by searching for and locating Docket
No. FAA-2021-0656.
(2) For more information about this AD, contact Chirayu Gupta,
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; fax 516-794-5531; 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 (IBR) 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-
26-20, Revision A, dated March 9, 2021.
(ii) [Reserved]
(3) For service information identified in this AD, contact De
Havilland Aircraft of Canada Limited, Q-Series Technical Help Desk,
123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone
416-375-4000; fax 416-375-4539; email [email protected]; internet
https://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: https://www.archives.gov/federal-register/cfr/ibr-locations.html.
Issued on October 26, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2021-26109 Filed 11-30-21; 8:45 am]
BILLING CODE 4910-13-P
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These are dated publication metadata, recorded clauses and literal source observations. Word, model-label, header and reference matches do not establish current legal effect, manufacturer/model identity, aircraft applicability, installed configuration or compliance.
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