[Federal Register Volume 86, Number 113 (Tuesday, June 15, 2021)]
[Rules and Regulations]
[Pages 31599-31601]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-12435]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0183; Project Identifier MCAI-2020-01408-T; 
Amendment 39-21589; AD 2021-12-02]
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.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain De Havilland Aircraft of Canada Limited Model DHC-8-400 series 
airplanes. This AD was prompted by a report that a number of nacelle A-
frames were not manufactured in accordance with engineering drawings. 
This AD requires, depending on airplane configuration, removing the 
fasteners on the nacelle A-frame side brace sub-assemblies, doing an 
eddy current inspection for cracking, cold-working the holes, 
installing oversize fasteners, re-identifying the reworked side brace 
fitting and A-frame, and repair if necessary. The FAA is issuing this 
AD to address the unsafe condition on these products.

DATES: This AD is effective July 20, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of certain publication listed in this AD as of July 20, 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 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-2021-0183.

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-
0183; 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: Antariksh Shetty, Aerospace Engineer, 
Airframe and Propulsion 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-2020-39, dated October 14, 
2020 (TCCA AD CF-2020-39) (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-8-400 
series 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-2021-0183.
    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-8-400 series airplanes. The NPRM 
published in the Federal Register on March 22, 2021 (86 FR 15149). The 
NPRM was prompted by a report that a number of nacelle A-frames were 
not manufactured in accordance with engineering drawings. The holes in 
the side brace sub-assemblies were not cold-worked as required. As a 
result the side brace fitting might not meet its fatigue life, and 
cracking of the A-frame bottom flange may result. The NPRM proposed to 
require, depending on airplane configuration, removing the fasteners on 
the nacelle A-frame side brace sub-assemblies, doing an eddy current 
inspection for cracking, cold-working the holes, installing oversize 
fasteners, re-identifying the reworked side brace fitting and A-frame, 
and repair if necessary. The FAA is issuing this AD to address possible 
cracking of the A-frame. This condition, if not addressed, may lead to 
collapse of the main landing gear (MLG). 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:
     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 
84-54-32, dated October 10, 2019. This service information describes 
procedures, depending on airplane configuration, for removing the 
fasteners on the nacelle A-frame side brace sub-assemblies, doing an 
eddy current inspection for cracking, cold-working the holes, 
installing oversize fasteners, and re-identifying the reworked side 
brace fitting and A-frame.
    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 41 airplanes of U.S. 
registry. The

[[Page 31600]]

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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15 work-hours x $85 per hour = $1,275........................            $254           $1,529          $62,689
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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

    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:

2021-12-02 De Havilland Aircraft of Canada Limited (Type Certificate 
Previously Held by Bombardier, Inc.): Amendment 39-21589; Docket No. 
FAA-2021-0183; Project Identifier MCAI-2020-01408-T.

(a) Effective Date

    This airworthiness directive (AD) is effective July 20, 2021.

(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-8-400, -
401, and -402 airplanes, certificated in any category, serial 
numbers 4081 through 4591 inclusive.

(d) Subject

    Air Transport Association (ATA) of America Code 54, Nacelles/
pylons.

(e) Reason

    This AD was prompted by a report that a number of nacelle A-
frames were not manufactured in accordance with engineering 
drawings. The holes in the side brace sub-assemblies were not cold-
worked as required. As a result the side brace fitting might not 
meet its fatigue life, and cracking of the A-frame bottom flange may 
result. The FAA is issuing this AD to address possible cracking of 
the A-frame. This condition, if not addressed, may lead to collapse 
of the main landing gear (MLG).

(f) Compliance

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

(g) Required Actions

    (1) Within the compliance time specified in paragraph (g)(2) of 
this AD, do the applicable actions specified in paragraphs (g)(1)(i) 
and (ii) of this AD.
    (i) For airplanes having serial numbers 4081 through 4582 
inclusive: Remove the fasteners on the nacelle A-frame side brace 
sub-assemblies, do an eddy current inspection for cracking on 
airplanes having 30,000 total flight cycles or more, cold-work the 
holes, and install oversize fasteners, in accordance with Part A of 
paragraph 3.B. of the Accomplishment Instructions of De Havilland 
Aircraft of Canada Limited Service Bulletin 84-54-32, dated October 
10, 2019. If any cracking is found, before further flight, repair 
the cracking 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.
    (ii) For all airplanes: Re-identify the reworked side brace 
fitting and A-frame, in accordance with Part B of paragraph 3.B. of 
the Accomplishment Instructions of De Havilland Aircraft of Canada 
Limited Service Bulletin 84-54-32, dated October 10, 2019.
    (2) At the earlier of the times specified in paragraphs 
(g)(2)(i) and (ii) of this AD, do the applicable actions specified 
in paragraph (g)(1) of this AD.
    (i) Within 48 months or 8,000 flight hours after the effective 
date of this AD, whichever occurs first.
    (ii) At the later of the times specified in paragraphs 
(g)(2)(ii)(A) and (B) of this AD.
    (A) Before accumulating 40,000 total flight cycles.
    (B) Within 12 months or 1,290 flight cycles after the effective 
date of this AD, whichever occurs first.

(h) 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

[[Page 31601]]

by the Manager, New York ACO Branch, FAA; or TCCA; or De Havilland 
Aircraft of Canada Limited's TCCA DAO. If approved by the DAO, the 
approval must include the DAO-authorized signature.

(i) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
(MCAI) TCCA AD CF-2020-39, dated October 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-2021-0183.
    (2) For more information about this AD, contact Antariksh 
Shetty, Aerospace Engineer, Airframe and Propulsion 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].

(j) 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-
54-32, dated October 10, 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 May 25, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-12435 Filed 6-14-21; 8:45 am]
BILLING CODE 4910-13-P