[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]


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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.

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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 thd@dehavilland.com; 
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 9-avs-nyaco-cos@faa.gov.

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:
     Are consistent with the intent that was proposed in the 
NPRM for addressing the unsafe condition; and
     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.
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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 
9-avs-nyaco-cos@faa.gov.
    (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 thd@dehavilland.com; 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 fedreg.legal@nara.gov, 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


