Document ID: FAA-2022-0143-0005
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes
Posted Date: 2022-06-03T04:00Z

[Federal Register Volume 87, Number 107 (Friday, June 3, 2022)]
[Rules and Regulations]
[Pages 33627-33630]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-11758]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0143; Project Identifier MCAI-2021-01401-T; 
Amendment 39-22061; AD 2022-11-11]
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 (type certificate 
previously held by Bombardier, Inc.) Model DHC-8-401 and -402 
airplanes. This AD was prompted by reports of a certain bolt at the 
pivot pin link being found missing or having stress corrosion cracking. 
This AD requires a modification to the nose landing gear (NLG) shock 
strut assembly. The FAA is issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective July 8, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of July 8, 
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-2022-0143.

[[Page 33628]]

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-2022-
0143; 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; email [email protected].

SUPPLEMENTARY INFORMATION: 

Background

    Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued AD CF-2009-29R4, dated October 1, 2021 
(TCCA AD CF-2009-29R4) (also referred to after this 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-2022-0143.
    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 (type certificate previously held by 
Bombardier, Inc.) Model DHC-8-401 and -402 airplanes. The NPRM 
published in the Federal Register on February 23, 2022 (87 FR 10112). 
The NPRM was prompted by reports of a certain bolt at the pivot pin 
link being found missing or having stress corrosion cracking. The NPRM 
proposed to require a modification to the NLG shock strut assembly. The 
FAA is issuing this AD to address failure of the pivot pin retention 
bolt, which could result in a loss of directional control or loss of an 
NLG tire during takeoff or landing, which could lead to runway 
excursions. See the MCAI for additional background information.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from Air Line Pilots Association, 
International (ALPA), who supported the NPRM without change.
    The FAA received additional comments from Horizon Air. The 
following presents the comments received on the NPRM and the FAA's 
response to each comment.

Request to Issue a Single AD

    Horizon Air requested that the FAA issue a single AD instead of 
both AD 2021-25-12, Amendment 39-21856 (86 FR 72174, December 21, 2021) 
(AD 2021-25-12), and this AD. Horizon Air noted that in the 
``Relationship Between Proposed AD and AD 2021-25-12'' paragraph of the 
NPRM, it stated it was determined that a stand-alone AD would be more 
appropriate. Horizon Air pointed out this AD and AD 2021-25-12 were 
both prompted by the same unsafe condition and the applicability is the 
same. Horizon Air suggested that this final rule replace AD 2021-25-12 
in order to have the subject matter mandates in a singular rule. 
Horizon Air concluded that having the new AD state the retained 
requirements and new requirements would promote compliance, be 
historically consistent, and be congruent with the related Transport 
Canada airworthiness directive (TCCA AD CF-2009-29R4).
    The FAA disagrees with the commenter's request. The FAA 
acknowledges that a single AD is typically more appropriate. However, 
AD 2021-25-12 is an immediately adopted rule (i.e., a final rule; 
request for comment) that includes actions with short compliance times. 
The FAA could not include Part I of TCCA AD CF-2009-29R4 in AD 2021-25-
12 due to the longer compliance time for the required modification, 
which necessitated issuing an NPRM with a public comment period. The 
FAA considered superseding AD 2021-25-12 to include retained actions 
and the modification, which has a 1,600 flight cycles or 9-month 
compliance time. However, issuing an NPRM to supersede AD 2021-25-12 
would have delayed the rulemaking process. The FAA determined issuing a 
stand-alone NPRM for the modification addresses the unsafe condition in 
a timely manner as the final rule for the stand-alone NPRM (this AD) 
will be published sooner than when a final rule for an NPRM that 
supersedes AD 2021-25-12 would be published. The FAA has not changed 
this AD in this regard.

Request To Include a Statement To Indicate the Association With AD 
2021-25-12

    Horizon Air requested that the FAA include a statement to indicate 
the association with AD 2021-25-12. Horizon Air stated that the actions 
required by AD 2021-25-12 are only applicable to airplanes with pivot 
pin retention bolt part number (P/N) NAS6204-14D installed on the NLG 
assembly; consequently, if this part is not installed the rule is not 
applicable. Horizon Air also stated that this AD mandates the 
installation of this part. Horizon Air concluded that a statement 
indicating the association with AD 2021-25-12 would enhance the 
awareness of the compliance requirements.
    The FAA concurs with the commenter's request. The actions required 
by AD 2021-25-12 only apply to airplanes that have installed pivot pin 
retention bolt P/N NAS6204-14D in the NLG assembly and therefore do not 
apply to those airplanes that do not have that pivot pin retention bolt 
installed. The modification required by paragraph (g) of this AD 
results in the installation of pivot pin retention bolt P/N NAS6204-
14D. After an operator has complied with this AD, the operator is then 
subject to AD 2021-25-12. As specified in paragraph (g) of AD 2021-25-
12, the operator must revise the existing maintenance or inspection 
program ``. . . within 30 days after the installation of pivot pin 
retention bolt part number P/N NAS6204-14D. . . .'' As specified in 
paragraph (i) of AD 2021-25-12, repetitive lubrications of the part are 
required at intervals not to exceed 400 flight cycles. The FAA has 
added Note 1 to paragraph (g) of this AD to refer to AD 2021-25-12 
after installing pivot pin retention bolt P/N NAS6204-14D.

Conclusion

    The FAA reviewed the relevant data, considered the comments 
received, and determined that air safety requires adopting this AD as 
proposed. Except for minor editorial changes, and any other changes 
described previously, this AD is adopted as proposed in the NPRM. None 
of the changes will increase the economic burden on any operator. 
Accordingly, the FAA is issuing this AD to address the unsafe condition 
on these products.

Related Service Information Under 1 CFR Part 51

    De Havilland Aircraft of Canada Limited has issued Service Bulletin 
84-32-161, Revision B, dated March 31,

[[Page 33629]]

2021, including UTC Aerospace Systems Service Bulletin 47100-32-145, 
Revision 3, dated March 26, 2021. This service information describes 
procedures for modifying the NLG shock strut assembly by replacing 
special bolt, part number (P/N) 47205-1 or 47205-3, with a new 
retention bolt, P/N NAS6204-14D (the modification includes a reverse 
orientation of the retention bolt and a rework of the weight on wheel 
(WOW) proximity sensor cover to provide clearance for the re-oriented 
retention bolt).
    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.

Difference Between This AD and the MCAI

    This AD only requires the modification specified in Part I of TCCA 
AD CF-2009-29R4. The other actions specified in TCCA AD CF-2009-29R4 
are required by FAA AD 2021-25-12.

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
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                                                                                    Cost per       Cost on U.S.
                          Labor cost                              Parts cost        product         operators
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4 work-hours x $85 per hour = $340...........................              $8             $348          $18,792
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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.

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:

2022-11-11 De Havilland Aircraft of Canada Limited (Type Certificate 
Previously Held by Bombardier, Inc.): Amendment 39-22061; Docket No. 
FAA-2022-0143; Project Identifier MCAI-2021-01401-T.

(a) Effective Date

    This airworthiness directive (AD) is effective July 8, 2022.

(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-8-401 and 
-402 airplanes, certificated in any category, serial numbers 4001 
and 4003 and subsequent.

(d) Subject

    Air Transport Association (ATA) of America Code 32, Landing 
gear.

(e) Unsafe Condition

    This AD was prompted by reports of a certain bolt at the pivot 
pin link being found missing or having stress corrosion cracking. 
The FAA is issuing this AD to address failure of the pivot pin 
retention bolt, which could result in a loss of directional control 
or loss of a nose landing gear (NLG) tire during takeoff or landing, 
which could lead to runway excursions.

(f) Compliance

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

(g) Modification

    For any airplane having an NLG shock strut assembly, part number 
(P/N) 47100-XX (where XX represents any number), that has special 
bolt P/N 47205-1 or 47205-3: Within 1,600 flight cycles or 9 months 
after the effective date of this AD, whichever occurs first, modify 
the NLG shock strut assembly, in accordance with paragraph 3.B., 
``Procedure,'' of the Accomplishment Instructions of De Havilland 
Aircraft of Canada Limited Service Bulletin 84-32-161, Revision B, 
dated March 31, 2021, including UTC Aerospace Systems Service 
Bulletin 47100-32-145, Revision 3, dated March 26, 2021.

    Note 1 to paragraph (g):  After installing pivot pin retention 
bolt part number NAS6204-14D, AD 2021-25-12, Amendment 39-21856 (86 
FR 72174, December 21, 2021) applies to pivot pin retention bolt 
part number NAS6204-14D.

(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 84-32-161, dated April 7, 2020, including UTC 
Aerospace Systems Service Bulletin 47100-32-145, dated April 3, 
2020; or De Havilland Aircraft of Canada Limited Service Bulletin 
84-32-161, Revision A, dated January 27, 2021, including UTC 
Aerospace Systems Service Bulletin 47100-32-145, Revision 2, dated 
January 4, 2021.

(i) Other FAA AD Provisions

    The following provisions also apply to this AD:

[[Page 33630]]

    (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-2009-29R4, dated October 1, 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-2022-0143.
    (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].
    (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-
32-161, Revision B, dated March 31, 2021, including UTC Aerospace 
Systems Service Bulletin 47100-32-145, Revision 3, dated March 26, 
2021.

    Note 2 to paragraph (k)(2)(i): De Havilland issued De Havilland 
Service Bulletin 84-32-161, Revision B, dated March 31, 2021, with 
UTC Aerospace Systems Service Bulletin 47100-32-145, Revision 3, 
dated March 26, 2021, attached as one ``merged'' file for the 
convenience of affected operators.

    (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 17, 2022.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2022-11758 Filed 6-2-22; 8:45 am]
BILLING CODE 4910-13-P