Published 2021-05-27 · Federal Register document 2021-11088
Airworthiness Directives; De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes
Publication summary
The FAA is superseding Airworthiness Directive (AD) 2015-17- 08, which applied to certain Bombardier, Inc. Model DHC-8-400 series airplanes. AD 2015-17-08 required installing new cable assemblies with a pull-down resistor. This AD requires modifications to the nose wheel steering (NWS) system. This AD was prompted by a report indicating that several failure modes of the NWS system may cause the loss of feedback from both rotary variable differential transformers to the steering control unit. 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[170]
- Raw source SHA-256
- 9c919420683447c683ad0c877cb886e341c11862be32b47c536a001b1d76dcb5
Final-rule publication
Recorded publication clauses
- AD identifier printed in this edition
- 2021-10-13
- Effective date printed in this edition
- 2021-07-01
Read 11 complete recorded clauses
Effective Date
(a) Effective Date
This airworthiness directive (AD) is effective July 1, 2021.
Exact source excerpt. Text positions 9394–9480, end exclusive, in the original decoded publication. SHA-256: 565eabf7ab92e024f327b31a3d429931b0ce50d2a3301ece9dbee45b5a679def
Affected ADs
(b) Affected ADs
This AD replaces AD 2015-17-08, Amendment 39-18241 (80 FR 51459,
August 25, 2015) (AD 2015-17-08).
Exact source excerpt. Text positions 9480–9603, end exclusive, in the original decoded publication. SHA-256: 0c244501fd4dfe145d8ea1541bc42223fefe11ebd6488c8732c92d02dcb37c3d
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 4608 inclusive.
Exact source excerpt. Text positions 9603–9808, end exclusive, in the original decoded publication. SHA-256: 500e998404a4dcf9fa880b302f059ff53fb35b2bc0740df683c4e6480fd7297e
Subject
(d) Subject
Air Transport Association (ATA) of America Code 32, Landing
gear.
Exact source excerpt. Text positions 9808–9893, end exclusive, in the original decoded publication. SHA-256: 69274928c56ed19d35a0daa54cffa9711e118fc8445a016c40a1122f318391b3
Reason
(e) Reason
This AD was prompted by a report indicating that several failure
modes of the nose wheel steering (NWS) system may cause the loss of
feedback from both rotary variable differential transformers to the
steering control unit. The FAA is issuing this AD to address failure
modes of the NWS system, which could lead to NWS runaway, loss of
directional control of the airplane, and possible consequent runway
excursion.
Exact source excerpt. Text positions 9893–10331, end exclusive, in the original decoded publication. SHA-256: d33d1c9eb808895fd695d0de34c7d6c71d58d2adac056a78139c60234c8cee37
Compliance
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
Exact source excerpt. Text positions 10331–10433, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3
New Requirement of This AD
(g) New Requirement of This AD
Within 4,000 flight hours or 18 months, whichever occurs first
after the effective date of this AD: Perform modifications to the
NWS system, in accordance with paragraph 3.B of the Accomplishment
Instructions of De Havilland Aircraft of Canada Limited Service
Bulletin 84-32-162, Revision B, dated November 13, 2019, including
UTC Aerospace Systems Service Bulletin 406300-32-142, dated June 24,
2019; and UTC Aerospace Systems Service Bulletin 406330-32-143,
dated June 24, 2019.
Exact source excerpt. Text positions 10433–10958, end exclusive, in the original decoded publication. SHA-256: 3abc29232d51b8e148ef178016d79ff7317fd7b7d2152bbc39e2b5534e8d4089
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 84-32-162, dated August 26, 2019, including UTC
Aerospace Systems Service Bulletin 406300-32-142, dated June 24,
2019, and UTC Aerospace Systems Service Bulletin 406330-32-143,
dated June 24, 2019; or De Havilland Aircraft of Canada Limited
Service Bulletin 84-32-162, Revision A, dated October 18, 2019,
including UTC Aerospace Systems Service Bulletin 406300-32-142,
dated June 24, 2019, and UTC Aerospace Systems
[[Page 28481]]
Service Bulletin 406330-32-143, dated June 24, 2019.
Exact source excerpt. Text positions 10958–11704, end exclusive, in the original decoded publication. SHA-256: 56539530c9e64000845965f4257fb400e8c9a29486fda2a4c10a1d76300d20e9
Other FAA AD Provisions
(i) Other FAA AD Provisions
(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 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 11704–12934, end exclusive, in the original decoded publication. SHA-256: d4f6712c3dec503db32177f0db03d9e8250d90252ec19e582cdb0e593cca739b
Related Information
(j) Related Information
(1) Refer to Mandatory Continuing Airworthiness Information
(MCAI) TCCA AD CF-2020-28, dated August 14, 2020, 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-2021-0018.
(2) For more information about this AD, contact Siddeeq Bacchus,
Aerospace Engineer, Mechanical Systems and Administrative Services
Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; telephone 516-228-7362; 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 12934–13711, end exclusive, in the original decoded publication. SHA-256: e8ab248ba8d04d8305400efb07ba73311410d0e2e4f25cf8d3e4b8592914c8df
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-
32-162, Revision B, dated November 13, 2019, including UTC Aerospace
Systems Service Bulletin 406300-32-142, dated June 24, 2019; and UTC
Aerospace Systems Service Bulletin 406330-32-143, dated June 24,
2019.
(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 13711–15219, end exclusive, in the original decoded publication. SHA-256: 571466db2725290943a0affbbf7e9ee4ff54e6a804ec7cfc6f62df807a2cd936
Explicit historical replacement wording
Find all recorded historical references to AD 2021-10-13 · 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: c5d7b587ccfe85d75812581899e28059669135df35f073197b6185675ae672a3. Source manifest: b15f38fa0fbd2800e72a6144f70d2ad9cc8f55a88dbaaa3f87454544f5693dd6.
Official source · 2021-05-27
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 101 (Thursday, May 27, 2021)]
[Rules and Regulations]
[Pages 28479-28481]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-11088]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2021-0018; Project Identifier MCAI-2020-01214-T;
Amendment 39-21546; AD 2021-10-13]
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 superseding Airworthiness Directive (AD) 2015-17-
08, which applied to certain Bombardier, Inc. Model DHC-8-400 series
airplanes. AD 2015-17-08 required installing new cable assemblies with
a pull-down resistor. This AD requires modifications to the nose wheel
steering (NWS) system. This AD was prompted by a report indicating that
several failure modes of the NWS system may cause the loss of feedback
from both rotary variable differential transformers to the steering
control unit. The FAA is issuing this AD to address the unsafe
condition on these products.
DATES: This AD is effective July 1, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of July 1,
2021.
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 referenced 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-2021-0018.
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-
0018; 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: Siddeeq Bacchus, Aerospace Engineer,
Mechanical Systems and Administrative Services Section, FAA, New York
ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
telephone 516-228-7362; fax 516-794-5531; email [email protected].
SUPPLEMENTARY INFORMATION:
Discussion
Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued TCCA AD CF-2020-28, dated August 14,
2020 (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-2021-0018.
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to supersede AD 2015-17-08, Amendment 39-18241 (80 FR
51459, August 25, 2015) (AD 2015-17-08). AD 2015-17-08 applied to
certain Bombardier, Inc. Model DHC-8-400 series airplanes. The NPRM
published in the Federal Register on February 24, 2021 (86 FR 11175).
The NPRM was prompted by a report indicating that several failure modes
of the NWS system may cause the loss of feedback from both rotary
variable differential transformers to the steering control unit. The
NPRM proposed to require modifications to the NWS system. The FAA is
issuing this AD to address failure modes of the NWS system, which could
lead to NWS runaway, loss of directional control of the airplane, and
possible consequent runway excursion. 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)
indicated its support for the NPRM.
[[Page 28480]]
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
84-32-162, Revision B, dated November 13, 2019, including UTC Aerospace
Systems Service Bulletin 406300-32-142, dated June 24, 2019; and UTC
Aerospace Systems Service Bulletin 406330-32-143, dated June 24, 2019.
This service information describes procedures for modifying the NWS
system (terminating wiring, reworking the left-hand console frame, and
installing an NWS electronic control unit and NWS hand control). 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:
Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
Modification.................. 13 work-hours x Up to $122......... Up to $1,227....... Up to $66,258.
$85 per hour =
$1,105.
----------------------------------------------------------------------------------------------------------------
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
The FAA determined that 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:
0
a. Removing Airworthiness Directive (AD) 2015-17-08, Amendment 39-18241
(80 FR 51459, August 25, 2015); and
0
b. Adding the following new AD:
2021-10-13 De Havilland Aircraft of Canada Limited (Type Certificate
Previously Held by Bombardier, Inc.): Amendment 39-21546; Docket No.
FAA-2021-0018; Project Identifier MCAI-2020-01214-T.
(a) Effective Date
This airworthiness directive (AD) is effective July 1, 2021.
(b) Affected ADs
This AD replaces AD 2015-17-08, Amendment 39-18241 (80 FR 51459,
August 25, 2015) (AD 2015-17-08).
(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 4608 inclusive.
(d) Subject
Air Transport Association (ATA) of America Code 32, Landing
gear.
(e) Reason
This AD was prompted by a report indicating that several failure
modes of the nose wheel steering (NWS) system may cause the loss of
feedback from both rotary variable differential transformers to the
steering control unit. The FAA is issuing this AD to address failure
modes of the NWS system, which could lead to NWS runaway, loss of
directional control of the airplane, and possible consequent runway
excursion.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) New Requirement of This AD
Within 4,000 flight hours or 18 months, whichever occurs first
after the effective date of this AD: Perform modifications to the
NWS system, in accordance with paragraph 3.B of the Accomplishment
Instructions of De Havilland Aircraft of Canada Limited Service
Bulletin 84-32-162, Revision B, dated November 13, 2019, including
UTC Aerospace Systems Service Bulletin 406300-32-142, dated June 24,
2019; and UTC Aerospace Systems Service Bulletin 406330-32-143,
dated June 24, 2019.
(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 84-32-162, dated August 26, 2019, including UTC
Aerospace Systems Service Bulletin 406300-32-142, dated June 24,
2019, and UTC Aerospace Systems Service Bulletin 406330-32-143,
dated June 24, 2019; or De Havilland Aircraft of Canada Limited
Service Bulletin 84-32-162, Revision A, dated October 18, 2019,
including UTC Aerospace Systems Service Bulletin 406300-32-142,
dated June 24, 2019, and UTC Aerospace Systems
[[Page 28481]]
Service Bulletin 406330-32-143, dated June 24, 2019.
(i) Other FAA AD Provisions
(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 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-2020-28, dated August 14, 2020, 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-2021-0018.
(2) For more information about this AD, contact Siddeeq Bacchus,
Aerospace Engineer, Mechanical Systems and Administrative Services
Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410,
Westbury, NY 11590; telephone 516-228-7362; 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-
32-162, Revision B, dated November 13, 2019, including UTC Aerospace
Systems Service Bulletin 406300-32-142, dated June 24, 2019; and UTC
Aerospace Systems Service Bulletin 406330-32-143, dated June 24,
2019.
(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 April 30, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2021-11088 Filed 5-26-21; 8:45 am]
BILLING CODE 4910-13-P
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