AD 2021-23-02

final rule

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

AD Number
2021-23-02
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2021-0656
FR Citation
86 FR 68107
Technical illustration of an aircraft landing gear and wheel assembly
Problem area Landing gear

Applicability

TypeManufacturerModelDetails
aircraft De Havilland Aircraft of Canada Limited DHC-8-401 Airworthiness Directives; De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes
aircraft De Havilland Aircraft of Canada Limited DHC-8-402 Airworthiness Directives; De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes

Unsafe Condition

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.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

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 doing all applicable corrective actions. Corrective actions include repair and replacement of the APD sensing line and the hydraulic tube assembly.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 48 months or 8,000 flight hours, whichever occurs first after the effective date of this AD

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

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.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

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.

Applicability Source Text

Show captured applicability text from the source AD
(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.

Document Text

Show stored source text (verify against official source)
[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 [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2021-26109]


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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 <a href="/cdn-cgi/l/email-protection#dbafb3bf9bbfbeb3baadb2b7b7bab5bff5b8b4b6"><span class="__cf_email__" data-cfemail="3d4955597d5958555c4b5451515c5359135e5250">[email&#160;protected]</span></a>; 
internet <a href="https://dehavilland.com">https://dehavilland.com</a>. 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 <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching 
for and locating Docket No. FAA-2021-0656.

Examining the AD Docket

    You may examine the AD docket on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> 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 <a href="/cdn-cgi/l/email-protection#c7feeaa6b1b4eaa9bea6a4a8eaa4a8b487a1a6a6e9a0a8b1"><span class="__cf_email__" data-cfemail="764f5b1700055b180f1715195b1519053610171758111900">[email&#160;protected]</span></a>.

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 
<a href="https://www.regulations.gov">https://www.regulations.gov</a> 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 <a href="https://www.regulations.gov">https://www.regulations.gov</a> 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 
<a href="/cdn-cgi/l/email-protection#a29b8fc3d4d18fccdbc3c1cd8fc1cdd1e2c4c3c38cc5cdd4"><span class="__cf_email__" data-cfemail="b38a9ed2c5c09eddcad2d0dc9ed0dcc0f3d5d2d29dd4dcc5">[email&#160;protected]</span></a>.
    (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 <a href="/cdn-cgi/l/email-protection#23574b476347464b42554a4f4f424d470d404c4e"><span class="__cf_email__" data-cfemail="04706c604460616c65726d6868656a602a676b69">[email&#160;protected]</span></a>; internet 
<a href="https://dehavilland.com">https://dehavilland.com</a>.
    (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 <a href="/cdn-cgi/l/email-protection#0a6c78246364797a6f697e6365644a646b786b246d657c"><span class="__cf_email__" data-cfemail="4422366a2d2a37342127302d2b2a042a2536256a232b32">[email&#160;protected]</span></a>, or go to: <a href="https://www.archives.gov/federal-register/cfr/ibr-locations.html">https://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.

    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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Retrieved: Apr 4, 2026

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