Document ID: FAA-2022-0672-0004
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes
Posted Date: 2022-08-31T04:00Z

[Federal Register Volume 87, Number 168 (Wednesday, August 31, 2022)]
[Proposed Rules]
[Pages 53424-53429]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-18749]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0672; Project Identifier MCAI-2020-01606-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: Supplemental notice of proposed rulemaking (SNPRM).

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SUMMARY: The FAA is revising a notice of proposed rulemaking (NPRM) to 
supersede Airworthiness Directive (AD) 2020-04-20, which applies to 
certain De Havilland Aircraft of Canada Limited Model DHC-8-400 series 
airplanes. This action revises the NPRM by including an additional 
retained requirement and revising the terminating action to apply to 
additional airplanes. The FAA is proposing this AD to address the 
unsafe condition on these products. Since these actions would impose an 
additional burden over those in the NPRM, the FAA is reopening the 
comment period to allow the public the chance to comment on these 
changes.

DATES: The FAA must receive comments on this SNPRM by October 17, 2022.

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 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 SNPRM, contact De 
Havilland Aircraft of Canada Limited, Dash 8 Series Customer Response 
Centre, 5800 Explorer Drive, Mississauga, Ontario, L4W 5K9, Canada; 
telephone North America (toll-free): 855-310-1013, Direct: 647-277-582; 
email dehavilland.com">[email protected]dehavilland.com; internet 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 regulations.gov under Docket No. 
FAA-2022-0672; or in person at Docket Operations between 9 a.m. and 5 
p.m., Monday through Friday, except Federal holidays. The AD docket 
contains, the NPRM, this SNPRM, the mandatory continuing airworthiness 
information (MCAI), any comments received, and other information. The 
street address for Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Joseph Catanzaro, Aerospace Engineer, 
Airframe and Propulsion Section, FAA, New York ACO Branch, 1600 Stewart 
Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7366; 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-2022-0672; Project Identifier 
MCAI-2020-01606-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 
this 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 
regulations.gov, including any personal information you provide. The 
agency will also post a report summarizing each substantive verbal 
contact received about this SNPRM.

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 SNPRM 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 SNPRM, 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 SNPRM. Submissions containing CBI should 
be sent to Joseph Catanzaro, Aerospace Engineer, Airframe and 
Propulsion Section, FAA, New York ACO Branch, 1600 Stewart Avenue, 
Suite 410, Westbury, NY 11590; telephone 516-228-7366; 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

    The FAA issued AD 2020-04-20, Amendment 39-19857 (85 FR 17473, 
March 30, 2020) (AD 2020-04-20) for certain De Havilland Aircraft of 
Canada Limited Model DHC-8-400 series airplanes. AD 2020-04-20 requires

[[Page 53425]]

repetitive inspections of certain parts for discrepancies that meet 
specified criteria, and replacement as necessary; repetitive 
inspections of certain parts for damage and wear, and rework of parts; 
and electrical bonding checks of certain couplings. AD 2020-04-20 also 
requires revising the existing maintenance or inspection program, as 
applicable, to incorporate new or more restrictive airworthiness 
limitations. For certain airplanes, AD 2020-04-20 allows a modification 
that terminates the repetitive inspections. The FAA issued AD 2020-04-
20 to address wear on fuel couplings, bonding springs, and sleeves as 
well as fuel tube end ferrules and fuel component end ferrules, which 
could reduce the integrity of the electrical bonding paths through the 
fuel line and components, and ultimately lead to fuel tank ignition in 
the event of a lightning strike.
    The FAA issued an NPRM to amend 14 CFR part 39 by adding an AD to 
supersede AD 2020-04-20 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 June 9, 2022 (87 FR 35128) (the 
NPRM). The NPRM was prompted by MCAI originated by Transport Canada 
Civil Aviation (TCCA), which is the aviation authority for Canada. TCCA 
issued AD CF-2017-04R3 to correct an unsafe condition identified as 
wear on fuel couplings, bonding springs, and sleeves as well as fuel 
tube end ferrules and fuel component end ferrules. The NPRM proposed to 
continue to require the actions in AD 2020-04-20, revise the 
applicability by adding airplanes, and require, for certain airplanes, 
the previously optional rework and retrofit of certain parts of the 
fuel system.

Actions Since the NPRM Was Issued

    Since the FAA issued the NPRM, the FAA determined that the NPRM 
inadvertently limited the proposed new terminating rework and retrofit 
to airplanes that had accomplished certain service information. In 
addition, the FAA determined that the optional terminating action 
specified in AD 2020-04-20, and corresponding credit, should be carried 
over to this proposed AD. These changes match the intent of TCCA AD CF-
2017-04R3.
    You may examine the MCAI in the AD docket at regulations.gov under 
Docket No. FAA-2022-0672.

Comments

    The FAA received a comment from the Air Line Pilots Association, 
International (ALPA) who supported the NPRM without change.

Additional Changes Made to This Proposed AD

    The FAA has replaced the content of paragraph (n)(3) of the 
proposed AD (in the NPRM) (which is paragraph (o)(3) of this proposed 
AD). Since this NPRM now includes the optional terminating action 
specified in AD 2020-04-02, the credit for that optional terminating 
action is now specified in paragraph (o)(3) of this proposed AD. In 
addition, the FAA has determined that the credit specified in paragraph 
(n)(3) of the proposed AD (in the NPRM) is a new provision and has 
moved the credit to paragraph (q) of this proposed AD and updated the 
wording for clarity and accuracy.

Related Service Information Under 1 CFR Part 51

    This proposed AD would require the following service information, 
which the Director of the Federal Register approved for incorporation 
by reference as of May 4, 2020 (85 FR 17473, March 30, 2020).
     Bombardier Service Bulletin 84-28-20, Revision D, dated 
November 23, 2018.
     Bombardier Service Bulletin 84-28-21, Revision C, dated 
July 13, 2018.
     Bombardier Service Bulletin 84-28-26, Revision A, dated 
November 29, 2018.
     Q400 Dash 8 (Bombardier) Temporary Revision ALI-0192, 
dated April 24, 2018.
     Q400 Dash 8 (Bombardier) Temporary Revision ALI-0193, 
dated April 24, 2018.
    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, it 
has notified the FAA of the unsafe condition described in the MCAI and 
service information referenced above. The FAA is issuing this SNPRM 
after determining that the unsafe condition described previously is 
likely to exist or develop on other products of the same type design.
    Certain changes described above expand the scope of the NPRM. As a 
result, it is necessary to reopen the comment period to provide 
additional opportunity for the public to comment on this SNPRM.

Proposed Requirements of This SNPRM

    This proposed AD would retain all of the requirements of AD 2020-
04-20. This proposed AD would require reworking and retrofitting 
certain parts of the fuel system. Doing the rework and retrofit would 
terminate the inspections in this proposed AD.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 54 airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                         Estimated Costs for Required Actions *
--------------------------------------------------------------------------------------------------------------------------------------------------------
                Action                          Labor cost           Parts cost             Cost per product                 Cost on U.S. operators
--------------------------------------------------------------------------------------------------------------------------------------------------------
Retained actions from AD 2020-04-20...  268 work-hours x $85 per               $0  $22,780...........................  $1,230,120.
                                         hour = $22,780.
New proposed actions..................  Up to 1,747 work-hours x           87,385  Up to $235,880....................  Up to $12,737,520.
                                         $85 per hour = Up to
                                         $148,495.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Table does not include estimated costs for revising the existing maintenance or inspection program.

    The FAA has determined that revising the existing maintenance or 
inspection program takes an average of 90 work-hours per operator, 
although the FAA recognizes that this number may vary from operator to 
operator. In the past, the FAA has estimated that this action takes 1 
work-hour per airplane. Since operators incorporate maintenance or 
inspection program changes for their affected fleet(s), the FAA has 
determined that a per-operator estimate is more accurate than a per-
airplane estimate. Therefore, the FAA estimates

[[Page 53426]]

the total cost per operator to be $7,650 (90 work-hours x $85 per work-
hour).

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:
0
a. Removing Airworthiness Directive (AD) 2020-04-20, Amendment 39-19857 
(85 FR 17473, March 30, 2020); and
0
b. Adding the following new AD:

De Havilland Aircraft of Canada Limited (Type Certificate previously 
held by Bombardier, Inc.): Docket No. FAA-2022-0672; Project 
Identifier MCAI-2020-01606-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by October 17, 2022.

(b) Affected ADs

    This AD replaces AD 2020-04-20, Amendment 39-19857 (85 FR 17473, 
March 30, 2020) (AD 2020-04-20).

(c) Applicability

    This AD applies to De Havilland Aircraft of Canada Limited Model 
DHC-8-400, -401, and -402 airplanes, certificated in any category, 
manufacturer serial numbers 4001 and 4003 and subsequent.

(d) Subject

    Air Transport Association (ATA) of America Code 28, Fuel.

(e) Reason

    This AD was prompted by reports of wear on fuel couplings, 
bonding springs, and sleeves as well as fuel tube end ferrules and 
fuel component end ferrules, and by a determination that a more 
robust lightning ignition protection design is necessary. The FAA is 
issuing this AD to address such wear, which could reduce the 
integrity of the electrical bonding paths through the fuel line and 
components, and ultimately lead to fuel tank ignition in the event 
of a lightning strike.

(f) Compliance

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

(g) Retained Initial Inspection Compliance Times, With New Terminating 
Action

    This paragraph restates the requirements of paragraph (g) of AD 
2020-04-20, with new terminating action. For airplanes having serial 
numbers 4001 and 4003 through 4575 inclusive that, as of May 4, 2020 
(the effective date of AD 2020-04-20), have not done the actions 
specified in Bombardier Service Bulletin 84-28-21: At the applicable 
times specified in paragraph (g)(1) or (2) of this AD, do the 
actions specified in paragraphs (h)(1) and (2) of this AD. 
Accomplishing the terminating action required by paragraph (p) of 
this AD terminates the initial inspection required by this 
paragraph.
    (1) For all airplanes except those identified in paragraph 
(g)(2) of this AD: Within 6,000 flight hours or 36 months, whichever 
occurs first after May 4, 2020 (the effective date of AD 2020-04-
20).
    (2) For airplanes with an original airworthiness certificate or 
original export certificate of airworthiness issued on or after May 
4, 2020 (the effective date of AD 2020-04-20): Within 6,000 flight 
hours or 36 months, whichever occurs first after the date of 
issuance of the original airworthiness certificate or the date of 
issuance of the original export certificate of airworthiness.

(h) Retained Repetitive Inspections and Corrective Actions, With New 
Terminating Action

    This paragraph restates the requirements of paragraph (h) of AD 
2020-04-20, with new terminating action. For airplanes having serial 
numbers 4001 and 4003 through 4575 inclusive that, as of May 4, 2020 
(the effective date of AD 2020-04-20), have not done the actions 
specified in Bombardier Service Bulletin 84-28-21: At the applicable 
times specified in paragraph (g)(1) or (2) of this AD, do the 
actions specified in paragraphs (h)(1) and (2) of this AD. Repeat 
the actions thereafter at intervals not to exceed 6,000 flight hours 
or 36 months, whichever occurs first. Accomplishing the terminating 
action required by paragraph (p) of this AD terminates the 
repetitive inspections required by this paragraph.
    (1) Do a detailed inspection of the clamshell coupling bonding 
wires, fuel couplings, and associated sleeves for discrepancies that 
meet specified criteria, as identified in, and in accordance with, 
paragraph 3.B., ``Procedure,'' of the Accomplishment Instructions of 
Bombardier Service Bulletin 84-28-20, Revision D, dated November 23, 
2018. If any conditions are found meeting the criteria specified in 
Bombardier Service Bulletin 84-28-20, Revision D, dated November 23, 
2018, before further flight, replace affected parts with new 
couplings and sleeves of the same part number, in accordance with 
paragraph 3.B., ``Procedure,'' of the Accomplishment Instructions of 
Bombardier Bulletin 84-28-20, Revision D, dated November 23, 2018.
    (2) Do a detailed inspection of the fuel tube end ferrules, fuel 
component end ferrules, and ferrule O-ring flanges for damage and 
wear, and rework (repair, replace, or blend, as applicable) the 
parts, in accordance with paragraph 3.B., ``Procedure,'' of the 
Accomplishment Instructions of Bombardier Service Bulletin 84-28-20, 
Revision D, dated November 23, 2018.

(i) Retained Optional Terminating Action for Repetitive Inspections 
With No Changes

    This paragraph restates the requirements of paragraph (i) of AD 
2020-04-20, with no changes. For airplanes having serial numbers 
4001 and 4003 through 4575 inclusive: Doing a detailed inspection of 
the fuel tube end ferrules, fuel component end ferrules, and ferrule 
O-ring flanges for damage and wear, and reworking (repair, replace, 
or blend, as applicable) the parts; and doing a retrofit (structural 
rework) of the fuel couplings, isolators, and structural provisions, 
in accordance with paragraph 3.B., ``Procedure,'' of the 
Accomplishment Instructions of Bombardier Service Bulletin 84-28-21, 
Revision C, dated July 13, 2018, terminates the inspections 
specified in paragraphs (h)(1) and (2) of this AD.

[[Page 53427]]

(j) Retained Electrical Bonding Checks/Detailed Inspection, With No 
Changes

    This paragraph restates the requirements of paragraph (j) of AD 
2020-04-20, with no changes. For airplanes having serial numbers 
4001, 4003 through 4489 inclusive, and 4491 through 4575 inclusive 
that, as of May 4, 2020 (the effective date of AD 2020-04-20), have 
done the actions specified in Bombardier Service Bulletin 84-28-21, 
Revision A, dated September 29, 2017; and airplanes having serial 
numbers 4576 through 4581 inclusive: Within 6,000 flight hours or 36 
months after May 4, 2020, whichever occurs first, do the actions 
specified in paragraph (j)(1) or (2) of this AD.
    (1) Accomplish electrical bonding checks of all threaded 
couplings on the inboard vent lines in the left and right wings, in 
accordance with paragraph 3.B., ``Procedure,'' of the Accomplishment 
Instructions of Bombardier Service Bulletin 84-28-26, Revision A, 
dated November 29, 2018.
    (2) Do a detailed inspection of the fuel tube end ferrules, fuel 
component end ferrules, and ferrule O-ring flanges for damage and 
wear, and rework (repair, replace, or blend, as applicable) the 
parts; and a retrofit (structural rework) of the fuel couplings, 
isolators, and structural provisions; in accordance with paragraph 
3.B., ``Procedure,'' of the Accomplishment Instructions of 
Bombardier Service Bulletin 84-28-21, Revision C, dated July 13, 
2018.

(k) Retained Revision of the Existing Maintenance or Inspection 
Program, With No Changes

    This paragraph restates the requirements of paragraph (k) of AD 
2020-04-20, with no changes. Within 30 days after May 4, 2020 (the 
effective date of AD 2020-04-20), revise the existing maintenance or 
inspection program, as applicable, to incorporate the information 
specified in Q400 Dash 8 (Bombardier) Temporary Revision ALI-0192, 
dated April 24, 2018; and Q400 Dash 8 (Bombardier) Temporary 
Revision ALI-0193, dated April 24, 2018. Except as specified in 
paragraph (l) of this AD, the initial compliance time for doing the 
tasks in Q400 Dash 8 (Bombardier) Temporary Revision ALI-0192, dated 
April 24, 2018, is at the time specified in Q400 Dash 8 (Bombardier) 
Temporary Revision ALI-0192, dated April 24, 2018, or within 30 days 
after May 4, 2020, whichever occurs later.

(l) Retained Initial Compliance Time for Task 284000-419, With No 
Changes

    This paragraph restates the requirements of paragraph (l) of AD 
2020-04-20, with no changes. The initial compliance time for task 
284000-419 is at the time specified in paragraph (l)(1) or (2) of 
this AD, as applicable, or within 30 days after May 4, 2020 (the 
effective date of AD 2020-04-20), whichever occurs later.
    (1) For airplanes having serial numbers 4001 and 4003 through 
4575 inclusive: Within 18,000 flight hours or 108 months, whichever 
occurs first, after the earliest date of embodiment of Bombardier 
Service Bulletin 84-28-21 on the airplane.
    (2) For airplanes having serial numbers 4576 and subsequent: 
Within 18,000 flight hours or 108 months, whichever occurs first, 
from the date of issuance of the original airworthiness certificate 
or original export certificate of airworthiness.

(m) Retained No Alternative Actions, Intervals, or Critical Design 
Configuration Control Limitations (CDCCLs), With No Changes

    This paragraph restates the requirements of paragraph (m) of AD 
2020-04-20, with no changes. After the existing maintenance or 
inspection program has been revised as required by paragraph (k) of 
this AD, no alternative actions (e.g., inspections), intervals, or 
CDCCLs may be used unless the actions, intervals, and CDCCLs are 
approved as an alternative method of compliance (AMOC) in accordance 
with the procedures specified in paragraph (r)(1) of this AD.

(n) Retained No Reporting Provisions, With No Changes

    This paragraph restates the provisions of paragraph (n) of AD 
2020-04-20, with no changes. Although Bombardier Service Bulletin 
84-28-20, Revision D, dated November 23, 2018, specifies to submit 
certain information to the manufacturer, this AD does not include 
that requirement.

(o) Retained Credit for Previous Actions, With No Changes

    (1) This paragraph restates the provisions of paragraph (o) of 
AD 2020-04-20, with no changes. This paragraph provides credit for 
the actions required by paragraphs (h)(1) and (2) of this AD, if 
those actions were performed before May 4, 2020 (the effective date 
of AD 2020-04-20), using the service information specified in 
paragraph (o)(1)(i) through (iii) of this AD.
    (i) Bombardier Service Bulletin 84-28-20, Revision A, dated 
December 14, 2016.
    (ii) Bombardier Service Bulletin 84-28-20, Revision B, dated 
February 13, 2017.
    (iii) Bombardier Service Bulletin 84-28-20, Revision C, dated 
April 28, 2017.
    (2) For the airplane having serial number 4164, this paragraph 
provides credit for the initial inspections required by paragraphs 
(h)(1) and (2) of this AD, if those actions were performed before 
May 4, 2020 (the effective date of AD 2020-04-20), using Bombardier 
Service Bulletin 84-28-20, dated September 30, 2016.
    (3) This paragraph provides credit for the actions specified in 
paragraph (i) of this AD if those actions were performed before May 
4, 2020 (the effective date of AD 2020-04-20), using the service 
information specified in paragraph (o)(3)(i) through (iii) of this 
AD.
    (i) Bombardier Service Bulletin 84-28-21, dated August 31, 2017.
    (ii) Bombardier Service Bulletin 84-28-21, Revision A, dated 
September 29, 2017.
    (iii) Bombardier Service Bulletin 84-28-21, Revision B, dated 
June 8, 2018.
    (4) This paragraph provides credit for the actions required by 
paragraph (j)(1) of this AD if those actions were performed before 
May 4, 2020 (the effective date of AD 2020-04-20), using Bombardier 
Service Bulletin 84-28-26, dated August 14, 2018.
    (5) This paragraph provides credit for the actions required by 
paragraph (j)(2) of this AD if those actions were performed before 
May 4, 2020 (the effective date of AD 2020-04-20), using Bombardier 
Service Bulletin 84-28-21, Revision B, dated June 8, 2018.
    (6) For airplanes having serial numbers 4001, 4003 through 4489 
inclusive, and 4491 through 4575 inclusive, and that are post 
Bombardier Service Bulletin 84-28-21, Revision A, dated September 
29, 2017: This paragraph provides credit for the actions required by 
paragraph (j) of this AD if those actions were performed before May 
4, 2020 (the effective date of AD 2020-04-20), using the service 
information specified in paragraph (o)(6)(i) or (ii) of this AD.
    (i) Bombardier Modification Summary Package (ModSum) 
IS4Q2800032, dated February 1, 2018.
    (ii) Any airworthiness limitation change request (ACR) specified 
in figure 1 to paragraph (o)(6)(ii) of this AD.

[[Page 53428]]

[GRAPHIC] [TIFF OMITTED] TP31AU22.004

(p) New Rework and Retrofit

    For airplanes having serial numbers 4001 and 4003 through 4575 
inclusive: At the applicable time specified in paragraph (p)(1) or 
(2) of this AD, rework (repair, replace, or blend, as applicable) 
the parts (fuel tube end ferrules, fuel component end ferrules, and 
ferrule O-ring flanges); and do a retrofit (structural rework) of 
the fuel couplings, isolators, and structural provisions; in 
accordance with Part B of paragraph 3.B., ``Procedure,'' of the 
Accomplishment Instructions of Bombardier Service Bulletin 84-28-21, 
Revision C, dated July 13, 2018. Accomplishing these actions 
terminates the initial and repetitive inspections required by 
paragraphs (g) and (h) of this AD.
    (1) For airplanes with greater than 20,000 total flight hours as 
of the effective date of this AD: Do the actions within 6,000 flight 
hours or 36 months after the effective date of this AD, whichever 
occurs first.
    (2) For airplanes with less than or equal to 20,000 total flight 
hours as of the effective date of this AD: Do the actions within 
8,000 flight hours or 48 months after the effective date of this AD, 
whichever occurs first.

(q) New Credit for Previous Actions

    This paragraph provides credit for the actions required by 
paragraph (p) of this AD, if those actions were performed before the 
effective date of this AD using the service information specified in 
paragraph (q)(1), (2), or (3) of this AD.
    (1) Bombardier Service Bulletin 84-28-21, dated August 31, 2017.
    (2) Bombardier Service Bulletin 84-28-21, Revision A, dated 
September 29, 2017.
    (3) Bombardier Service Bulletin 84-28-21, Revision B, dated June 
8, 2018.

(r) Additional 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 New York ACO 
Branch, mail it to ATTN: Program Manager, Continuing Operational 
Safety, at the address identified in paragraph (s)(2) of this AD or 
email to: [email protected]. If mailing information, also 
submit information by email. 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.

(s) Additional Information

    (1) Refer to TCCA AD CF-2017-04R3, dated April 1, 2020, for 
related information. This TCCA AD may be found in the AD docket at 
regulations.gov under Docket No. FAA-2022-0672.
    (2) For more information about this AD, contact Joseph 
Catanzaro, Aerospace Engineer, Airframe and Propulsion Section, FAA, 
New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 
11590; telephone 516-228-7366; email [email protected].
    (3) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (t)(4) and (5) of this AD.

(t) 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.
    (3) The following service information was approved for IBR on 
May 4, 2020 (85 FR 17473, March 30, 2020).
    (i) Bombardier Service Bulletin 84-28-20, Revision D, dated 
November 23, 2018.
    (ii) Bombardier Service Bulletin 84-28-21, Revision C, dated 
July 13, 2018.
    (iii) Bombardier Service Bulletin 84-28-26, Revision A, dated 
November 29, 2018.
    (iv) Bombardier Q400 Dash 8 (Bombardier) Temporary Revision ALI-
0192, dated April 24, 2018.
    (v) Q400 Dash 8 (Bombardier) Temporary Revision ALI-0193, dated 
April 24, 2018.
    (4) For service information identified in this AD, contact De 
Havilland Aircraft of Canada Limited, Dash 8 Series Customer 
Response Centre, 5800 Explorer Drive, Mississauga, Ontario, L4W 5K9, 
Canada; telephone North America (toll-free): 855-310-1013, Direct: 
647-277-5820; email dehavilland.com">[email protected]dehavilland.com; internet dehavilland.com.
    (5) 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

[[Page 53429]]

availability of this material at the FAA, call 206-231-3195.
    (6) 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: archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on August 25, 2022.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2022-18749 Filed 8-30-22; 8:45 am]
BILLING CODE 4910-13-P