[Federal Register Volume 87, Number 68 (Friday, April 8, 2022)]
[Rules and Regulations]
[Pages 20701-20703]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-07477]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0007; Project Identifier 2018-CE-048-AD; Amendment 
39-22002; AD 2022-07-14]
RIN 2120-AA64


Airworthiness Directives; Viking Air Limited (Type Certificate 
Previously Held by Bombardier Inc. and de Havilland, Inc.) Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Viking Air Limited (type certificate previously held by 
Bombardier Inc. and de Havilland, Inc.) Model DHC-6-400 airplanes. This 
AD was prompted by mandatory continuing airworthiness information 
(MCAI) originated by an aviation authority of another country to 
identify and correct an unsafe condition on an aviation product. The 
MCAI describes the unsafe condition as corrosion of the fuel system 
components located in the fuel gallery due to inadequate corrosion 
protection. This AD requires repetitively inspecting the fuel gallery 
for corrosion, rectifying any deficiencies, and accomplishing 
modifications to the fuel gallery system. The FAA is issuing this AD to 
address the unsafe condition on these products.

DATES: This AD is effective May 13, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of May 13, 2022.

ADDRESSES: For service information identified in this final rule, 
contact Viking Air Limited Technical Support, 1959 de Havilland Way, 
Sidney, British Columbia, Canada, V8L 5V5; phone: (North America) (800) 
663-8444; fax: (250) 656-0673; email: [email protected]; 
website: https://www.vikingair.com/support/service-bulletins. You may 
view this service information at the FAA, Airworthiness Products 
Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. 
For information on the availability of this material at the FAA, call 
(817) 222-5110. Service information that is incorporated by reference 
is also available at https://www.regulations.gov by searching for and 
locating Docket No. FAA-2022-0007.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2022-0007; 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, the 
MCAI, 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: Joseph Catanzaro, Aviation Safety 
Engineer, New York ACO Branch, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (516) 228-7366; email: 
[email protected].

SUPPLEMENTARY INFORMATION: 

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to certain serial-numbered 
Viking Air Limited (type certificate previously held by Bombardier Inc. 
and de Havilland, Inc.) Model DHC-6-400 airplanes. The NPRM published 
in the Federal Register on January 21, 2022 (87 FR 3238). The NPRM was 
prompted by MCAI originated by Transport Canada, which is the aviation 
authority for Canada. Transport Canada issued AD CF-2018-07, dated 
February 23, 2018 (referred to after this as ``the MCAI''), to address 
an unsafe condition on certain serial-numbered Viking Air Limited Model 
DHC-6-400 airplanes. The MCAI states:

    There have been reports of corrosion affecting components of the 
fuel system that are located in the fuel gallery because of 
inadequate corrosion protection. This condition affects only 
aeroplanes operating on floats.
    The effects of corrosion-related damage to fuel system 
components have included fuel

[[Page 20702]]

leaks, electrical arcing, loss of fuel boost pump function and 
erroneous fuel quantity readings. Inaccurate fuel quantity 
indication and loss of fuel boost pump function can lead to fuel 
starvation followed by loss of engine power. Electrical arcing in 
the fuel gallery and loss of electrical bonding between fuel system 
components increases the risk of fire.

    The MCAI requires repetitively inspecting the fuel gallery for 
corrosion, rectifying any deficiencies, and accomplishing modifications 
to the fuel gallery system. You may examine the MCAI in the AD docket 
at https://www.regulations.gov by searching for and locating Docket No. 
FAA-2022-0007.

Discussion of Final Airworthiness Directive

Comments

    The FAA received one comment on the NPRM from an individual. The 
commenter supported the NPRM without change.

Conclusion

    These products have been approved by the aviation authority of 
another country and are approved for operation in the United States. 
Pursuant to the FAA's bilateral agreement with this State of Design 
Authority, it has notified the FAA of the unsafe condition described in 
the MCAI referenced above. The FAA reviewed the relevant data, 
considered the comment received, and determined that air safety 
requires adopting this AD as proposed. Accordingly, the FAA is issuing 
this AD to address the unsafe condition on these products. This AD is 
adopted as proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Viking DHC-6 Twin Otter Service Bulletin No. V6/
0044, Revision B, dated September 13, 2021. The service information 
specifies incorporating multiple design improvement modifications in 
the fuel gallery.
    The FAA also reviewed Temporary Revision No. 241, dated July 27, 
2021, to the Viking DHC-6 Inspection Requirements Manual, PSM 1-6-7. 
Items 15.(1) and 15.(2) of this service information specify rinsing and 
inspecting the entire fuel gallery for corrosion; removing corrosion; 
reapplying any protective finishes; and removing and replacing any 
damaged components. The temporary revision updates the fuel gallery 
inspection to include airplanes with a new fuel probe (Modification 
(MOD) 6/2395).
    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.

Other Related Service Information

    The FAA reviewed the following technical bulletins, which contain 
instructions for the different modifications to components in the fuel 
gallery:
     Viking DHC-6 Twin Otter Technical Bulletin No. TBV6/00034, 
Revision NC, dated October 16, 2013 (MOD 6/2267);
     Viking DHC-6 Twin Otter Technical Bulletin No. TBV6/00084, 
Revision A, dated May 26, 2017 (MOD 6/2299);
     Viking DHC-6 Twin Otter Technical Bulletin No. V6/00099, 
Revision NC, dated December 23, 2016 (MOD 6/2389);
     Viking DHC-6 Twin Otter Technical Bulletin No. TBV6/00094, 
Revision NC, dated November 1, 2016 (MOD 6/2390);
     Viking DHC-6 Twin Otter Technical Bulletin No. V6/00100, 
Revision NC, dated February 20, 2017 (MOD 6/2393); and
     Viking DHC-6 Twin Otter Technical Bulletin No. V6/00152, 
Revision NC, dated January 29, 2021 (MOD 6/2464).

Costs of Compliance

    The FAA estimates that this AD affects 4 airplanes of U.S. 
registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                  Cost on U.S.
             Action                  Labor cost           Parts cost        Cost per airplane      operators
----------------------------------------------------------------------------------------------------------------
Inspect fuel gallery...........  3 work-hours x     Not applicable........  $255 per           $1,020 per
                                  $85 per hour =                             inspection cycle.  inspection
                                  $255.                                                         cycle.
MOD 6/2267--Fuel boost pump EMI  16 work-hours x    $4,762................  $6,122...........  $12,244 (for 2
 filter relocation.               $85 per hour =                                                affected
                                  $1,360.                                                       airplanes).
MOD 6/2299--Improved fuel boost  17 work-hours x    $42,290...............  $43,735..........  $131,205 (for 3
 pump.                            $85 per hour =                                                affected
                                  $1,445.                                                       airplanes).
MOD 6/2389--Electrical Bonding   18 work-hours x    $572..................  $2,102...........  $8,408 (for 4
 Fuel System Manifold Drain       $85 per hour =                                                affected
 Valve.                           $1,530.                                                       airplanes).
MOD 6/2390--Fuel probe,          20 work-hours x    $2,129................  $3,829...........  $11,487 (for 3
 improved mating electrical       $85 per hour =                                                affected
 connection.                      $1,700.                                                       airplanes).
MOD 6/2393--Fuel system          8 work-hours x     $225..................  $905.............  $3,620 (for 4
 manifold--drain valve.           $85 per hour =                                                affected
                                  $680.                                                         airplanes).
MOD 6/2464--Fuel pressure        10 work-hours x    $3,953................  $4,803...........  $14,409 (for 3
 switch replacement.              $85 per hour =                                                affected
                                  $850.                                                         airplanes).
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On-Condition Costs

    The extent of corrosion damage found during the inspections may 
vary significantly from airplane to airplane. The FAA has no way of 
determining how much corrosion damage may be found on each airplane, 
the cost for repairing corrosion damage on each airplane, or the number 
of airplanes that may require repair.

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.

[[Page 20703]]

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 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:

2022-07-14 Viking Air Limited (Type Certificate Previously Held by 
Bombardier Inc. and de Havilland, Inc.): Amendment 39-22002; Docket 
No. FAA-2022-0007; Project Identifier 2018-CE-048-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective May 13, 2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Viking Air Limited (type certificate 
previously held by Bombardier Inc. and de Havilland, Inc.) Model 
DHC-6-400 airplanes, serial numbers 845 through 957, certificated in 
any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 2800, Aircraft Fuel 
System.

(e) Reason

    This AD was prompted by mandatory continuing airworthiness 
information (MCAI) originated by an aviation authority of another 
country to identify and correct an unsafe condition on an aviation 
product. The MCAI describes the unsafe condition as corrosion of 
fuel system components located in the fuel gallery due to inadequate 
corrosion protection. The FAA is issuing this AD to prevent 
corrosion-related damage to fuel system components, which could lead 
to fuel leaks, electrical arcing, loss of fuel boost pump function, 
and erroneous fuel quantity readings. This unsafe condition, if not 
corrected, could result in fuel starvation with loss of engine power 
and increased risk of an in-flight fire with consequent loss of 
airplane control.

(f) Compliance

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

(g) Required Actions for Airplanes Operating on Floats on the Effective 
Date of This AD

    (1) Within 50 hours time-in-service (TIS) after the effective 
date of this AD or within 3 months after the effective date of this 
AD, whichever occurs first, and thereafter at intervals not to 
exceed 125 hours TIS, do the following actions:
    (i) Remove all fuel gallery covers and rinse the fuel gallery 
with water.
    (ii) Inspect the fuel gallery for corrosion and, if there is any 
corrosion, take all necessary corrective actions before further 
flight by following Item D.15(2) of Special Inspection 3 in 
Temporary Revision No. 241, dated July 27, 2021, to the Viking DHC-6 
Inspection Requirements Manual, PSM 1-6-7.
    (2) Within 12 months after the effective date of this AD, 
install the modifications applicable to your airplane serial number 
by following the Accomplishment Instructions, sections A. through 
E., in Viking DHC-6 Twin Otter Service Bulletin No. V6/0044, 
Revision B, dated September 13, 2021 (Viking SB V6/0044, Revision 
B).

(h) Required Actions for Airplanes Modified To Operate on Floats After 
the Effective Date of This AD

    Within 12 months after the airplane is modified to operate on 
floats, regardless of whether the landing gear is later modified 
back to non-float landing gear, install the modifications applicable 
to your airplane serial number by following the Accomplishment 
Instructions, sections A. through E., in Viking SB V6/0044, Revision 
B.

(i) Alternative Methods of Compliance (AMOCs)

    (1) 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 local Flight Standards District 
Office, as appropriate. If sending information directly to the 
manager of the certification office, send it to the attention of the 
person identified in paragraph (j)(1) of this AD.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(j) Related Information

    (1) For more information about this AD, contact Joseph 
Catanzaro, Aviation Safety Engineer, New York ACO Branch, FAA, 1600 
Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (516) 228-
7366; email: [email protected].
    (2) Refer to Transport Canada AD CF-2018-07, dated February 23, 
2018, for more information. You may examine the Transport Canada AD 
in the AD docket at https://www.regulations.gov by searching for and 
locating Docket No. FAA-2022-0007.

(k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference 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 the AD specifies otherwise.
    (i) Viking DHC-6 Twin Otter Service Bulletin No. V6/0044, 
Revision B, dated September 13, 2021.
    (ii) Temporary Revision No. 241, dated July 27, 2021, to the 
Viking DHC-6 Inspection Requirements Manual, PSM 1-6-7.
    (3) For service information identified in this AD, contact 
Viking Air Limited Technical Support, 1959 de Havilland Way, Sidney, 
British Columbia, Canada, V8L 5V5; phone: (North America) (800) 663-
8444; fax: (250) 656-0673; email: [email protected]; 
website: https://www.vikingair.com/support/service-bulletins.
    (4) You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 901 
Locust, Kansas City, MO 64106. For information on the availability 
of this material at the FAA, call (817) 222-5110.
    (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 March 25, 2022.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2022-07477 Filed 4-7-22; 8:45 am]
BILLING CODE 4910-13-P


