[Federal Register Volume 86, Number 122 (Tuesday, June 29, 2021)]
[Proposed Rules]
[Pages 34163-34165]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-13726]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
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 

  Federal Register / Vol. 86, No. 122 / Tuesday, June 29, 2021 / 
Proposed Rules  

[[Page 34163]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0514; Project Identifier MCAI-2020-01570-T]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain De Havilland Aircraft of Canada Limited Model DHC-8-400, -
401, and -402 airplanes. This proposed AD was prompted by a report that 
the epoxy primer on the internal bore of the nacelle and landing gear 
attachment pins was not applied, and corrosion on the internal bore of 
the wing rear spar attachment pins was found. This proposed AD would 
require doing a detailed visual inspection of the nacelle to wing rear 
spar attachment pins, and the nacelle and landing gear attachment pins, 
for any corrosion, and doing all applicable corrective actions. The FAA 
is proposing this AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by August 13, 
2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, 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.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-0514; 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 NPRM, any comments 
received, and other information. The street address for Docket 
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Deep Gaurav, 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: 

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2021-0514; Project Identifier 
MCAI-2020-01570-T'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
the proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this NPRM.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to Deep 
Gaurav, 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]. Any commentary that the FAA receives which is not 
specifically designated as CBI will be placed in the public docket for 
this rulemaking.

Background

    Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued TCCA AD CF-2020-51R1, dated February 
24, 2021 (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-8-400, -
401, and -402 airplanes. You may examine the MCAI in the AD docket at 
https://www.regulations.gov by searching for and locating Docket No. 
FAA-2021-0514.
    This proposed AD was prompted by a report that the epoxy primer on 
the internal bore of the nacelle and landing gear attachment pins was 
not applied, and corrosion on the internal bore of the wing rear spar 
attachment pins was found. The FAA is proposing this AD to

[[Page 34164]]

address premature corrosion and subsequent failure of the nacelle to 
landing gear and nacelle to rear wing spar attachment pins, which if 
undetected, could lead to a single or dual collapse of the main landing 
gear. See the MCAI for additional background information.

Related Service Information Under 1 CFR Part 51

    De Havilland Aircraft of Canada Limited has issued-Service Bulletin 
84-54-28, Revision B, dated January 24, 2020; and Service Bulletin 84-
54-31, Revision B, dated February 21, 2020. This service information 
describes procedures for doing a detailed visual inspection of the 
nacelle to wing rear spar attachment pins, and the nacelle and landing 
gear attachment pins, for any corrosion; and doing all applicable 
corrective actions. Corrective actions include applying epoxy primer to 
the bore surface of the pins, a fluorescent magnetic particle 
inspection for any cracking, corrosion removal, reworking and part 
marking certain pins, and replacing any cracked or corroded pins with 
serviceable pins. These documents are distinct since they apply to 
different airplane configurations.
    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.

FAA's Determination

    This product has been approved by the aviation authority of another 
country, and is approved for operation in the United States. Pursuant 
to the FAA's bilateral agreement with the State of Design Authority, 
the FAA has been notified of the unsafe condition described in the MCAI 
and service information referenced above. The FAA is proposing this AD 
because the FAA evaluated all the relevant information and determined 
the unsafe condition described previously is likely to exist or develop 
on other products of the same type design.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in the service information already described.

Differences Between This Proposed AD and the MCAI or Service 
Information

    Where Part III of TCCA CF-2020-51R1, dated February 24, 2021, 
specifies a detailed visual inspection and rectification of the nacelle 
and landing gear attachment pins, this AD requires a re-part mark of 
the yoke attachment pin as specified in Part B of the Accomplishment 
Instructions of De Havilland Service Bulletin 84-54-31, Revision B, 
dated February 21, 2020.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 41 airplanes of U.S. registry. The FAA estimates the following 
costs to comply with this proposed AD:

                                      Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
               Labor cost                   Parts cost         Cost per product         Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Up to 9 work-hours x $85 per hour = Up                $0  Up to $765................  Up to $31,365.
 to $765.
----------------------------------------------------------------------------------------------------------------

    The FAA has received no definitive data on which to base the cost 
estimates for the on-condition actions specified in this proposed AD.

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 proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would 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 Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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:

De Havilland Aircraft of Canada Limited (Type Certificate Previously 
Held by Bombardier, Inc.): Docket No. FAA-2021-0514; Project 
Identifier MCAI-2020-01570-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by August 13, 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 4001, 4003 through 4550 inclusive, 4583 through 4585 
inclusive, 4587, 4588, and 4590.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a report that the epoxy primer on the 
internal bore of the

[[Page 34165]]

nacelle and landing gear attachment pins was not applied, and 
corrosion on the internal bore of the wing rear spar attachment pins 
was found. The FAA is issuing this AD to address premature corrosion 
and subsequent failure of the nacelle to landing gear and nacelle to 
rear wing spar attachment pins, which if undetected, could lead to a 
single or dual collapse of the main landing gear.

(f) Compliance

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

(g) Inspection and Corrective Actions

    (1) At the applicable compliance times specified in paragraphs 
(g)(1)(i) through (iii) of this AD: Do a detailed visual inspection 
of the nacelle to wing rear spar attachment pins, and the nacelle 
and landing gear attachment pins, for any cracking or corrosion, and 
do all applicable corrective actions, in accordance with Part A or 
Part B, as applicable, of Section 3., ``Accomplishment 
Instructions,'' of the applicable service information specified in 
figure 1 to paragraph (g) of this AD. Do all applicable corrective 
actions before further flight.
[GRAPHIC] [TIFF OMITTED] TP29JN21.278

    (i) For nacelle to wing rear spar attachment pins, or nacelle 
and landing gear attachment pins, as applicable, that have 
accumulated less than 26,000 flight cycles as of the effective date 
of this AD, and have been in service less than 12 years from their 
entry-into-service as of the effective date of this AD: Prior to the 
pins reaching 14 years from their entry-into-service, or prior to 
the airplane reaching 30,000 total flight cycles, whichever occurs 
first.
    (ii) For nacelle to wing rear spar attachment pins, or nacelle 
and landing gear attachment pins, as applicable, that have 
accumulated 26,000 flight cycles or more as of the effective date of 
this AD, or have been in service 12 years or more from their entry-
into-service as of the effective date of this AD: Within 4 years or 
8,000 flight hours after the effective date of this AD, whichever 
occurs first.
    (iii) For airplanes on which the actions specified in Bombardier 
Service Bulletin 84-54-27, dated August 11, 2017; or Bombardier 
Service Bulletin 84-54-28, dated August 11, 2017; as applicable, 
have been accomplished: Within 14 years or 30,000 flight cycles 
after the date of incorporation of Bombardier Service Bulletin 84-
54-27, dated August 11, 2017; or Bombardier Service Bulletin 84-54-
28, dated August 11, 2017; as applicable, whichever occurs first.
    (2) For serial numbers 4583, 4584, 4585, 4587, 4588 and 4590: At 
the applicable compliance times specified in paragraphs (g)(1)(i) 
through (iii) of this AD, re-part mark the yoke attachment pin, in 
accordance with Part B of the Accomplishment Instructions of De 
Havilland Service Bulletin 84-54-31, Revision B, dated February 21, 
2020.

(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 the applicable service information specified 
in paragraphs (h)(1) through (3) of this AD.
    (1) Bombardier Service Bulletin 84-54-28, Revision A, dated 
April 10, 2019.
    (2) Bombardier Service Bulletin 84-54-31, dated May 1, 2019.
    (3) Bombardier Service Bulletin 84-54-31, Revision A, dated 
October 15, 2019.

(i) No Reporting Requirement

    Although De Havilland Service Bulletin 84-54-28, Revision B, 
dated January 24, 2020; and De Havilland Service Bulletin 84-54-31, 
Revision B, dated February 21, 2020; specify to submit certain 
information to the manufacturer, this AD does not include that 
requirement.

(j) 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 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.

(k) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
(MCAI) TCCA AD CF-2020-51R1, dated February 24, 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-2021-0514.
    (2) For more information about this AD, contact Deep Gaurav, 
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) 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. 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.

    Issued on June 23, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-13726 Filed 6-28-21; 8:45 am]
BILLING CODE 4910-13-P