[Federal Register Volume 87, Number 97 (Thursday, May 19, 2022)]
[Rules and Regulations]
[Pages 30405-30408]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-10758]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2022-0099; Project Identifier 2019-CE-019-AD; Amendment 
39-22045; AD 2022-10-07]
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 superseding Airworthiness Directive (AD) 89-24-06 
R1, which applied to all Boeing of Canada, Ltd. and de Havilland (now 
Viking Air Limited) Model DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 
airplanes. AD 89-24-06 R1 required repetitively inspecting the elevator 
quadrant for damage and taking corrective action as necessary. Since 
the FAA issued AD 89-24-06 R1, Transport Canada, the aviation authority 
for Canada, revised its mandatory continuing airworthiness information 
(MCAI) to correct this unsafe condition on these products. This AD 
retains the actions required by AD 89-24-06 R1, extends the compliance 
time intervals for the repetitive inspections, adds Model DHC-6-400 
airplanes to the applicability, and adds a fluorescent penetrant 
inspection requirement. The FAA is issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective June 23, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of June 23, 
2022.

[[Page 30406]]


ADDRESSES: For service information identified in this final rule, 
contact Viking Air Ltd., 1959 de Havilland Way, Sidney British 
Columbia, Canada V8L 5V5; phone: (800) 663-8444; email: 
[email protected]; website: https://www.vikingair.com. 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. It is also available at 
https://www.regulations.gov by searching for and locating Docket No. 
FAA-2022-0099.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2022-0099; 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: Darren Gassetto, Aviation Safety 
Engineer, New York ACO Branch, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (516) 228-7323; email: [email protected].

SUPPLEMENTARY INFORMATION:

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to supersede AD 89-24-06 R1, Amendment 39-6670 (Docket No. 
89-CE-29-AD; 55 FR 29347, July 19, 1990) (AD 89-24-06 R1). AD 89-24-06 
R1 applied to all Boeing of Canada, Ltd. and de Havilland (type 
certificate currently held by Viking Air Limited) Model DHC-6-1, DHC-6-
100, DHC-6-200, and DHC-6-300 airplanes. AD 89-24-06 R1 required 
repetitively inspecting the elevator quadrant, part number (P/N) C6CFM 
1138-27 (Pre Mod 6/1394), P/N C6CFM 1450-27 (Post Mod 6/1394 or 
production cut-in (PCI) serial number (S/N) 331, Pre Mod 6/1678), or P/
N C6CFM 1450-29 (Post Mod 6/1678 or PCI S/N 602), for distortion 
(warping, buckling, and score marks on the quadrant topside face caused 
by rubbing against the side of the cable guard) and replacing if 
distortion is found. AD 89-24-06 R1 also required inspecting the 
elevator quadrant mounting support bracket, P/N C6CFM 1142-1, for 
cracks if distortion in the elevator quadrant is found and replacing 
any cracked P/N C6CFM 1142-1. The FAA issued AD 89-24-06 R1 to prevent 
failure of the flight control system, which could result in loss of 
control of the airplane.
    The NPRM published in the Federal Register on February 11, 2022 (87 
FR 7965). The NPRM was prompted by Transport Canada AD CF-1972-06R5, 
dated June 22, 2018 (referred to after this as ``the MCAI''), issued by 
Transport Canada, which is the aviation authority for Canada. The MCAI 
states:

    Damage to the flight control system of DHC-6 aeroplanes was 
found during inspection. The damage has been attributed to ground 
gusts. The damage included cracks in the base of the lower control 
column, cracks and buckles in the elevator/rudder pulley bracket, 
and distortion of the elevator quadrant. Damage to the elevator 
quadrant may produce abnormal loads on the quadrant support bracket 
that damage the bracket.
    Damaged flight control components may fail when subjected to 
service loads, resulting in loss of control of the aeroplane.
    This revision of the [Transport Canada] AD clarifies the 
applicability of the corrective actions and endorses Service 
Bulletin (SB) 6/511 as a means of accomplishing some of the required 
inspections. In corrective action Part III, dye penetrant inspection 
has been replaced by fluorescent penetrant inspection.

    You may examine the MCAI in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2022-
0099.
    In the NPRM, the FAA proposed to retain the actions of AD 89-24-06 
R1, extend the compliance time intervals for the repetitive 
inspections, add Model DHC-6-400 airplanes to the applicability, and 
add a fluorescent penetrant inspection requirement.

Discussion of Final Airworthiness Directive

Comments

    The FAA received a comment from the Airline Pilots Association, 
International, which 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 the 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 6-511, 
Revision A, dated June 22, 1990. This service bulletin specifies 
procedures for repetitively inspecting the elevator quadrant for 
distortion (warping, buckling, and score marks), performing a one-time 
dye penetrant inspection of the elevator quadrant support bracket for 
cracks, and taking corrective actions. 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.

Differences Between This AD and the MCAI

    The MCAI addresses actions on the control column lower assembly, 
the elevator pulley bracket system, and the elevator quadrant. This AD 
only requires actions on the elevator quadrant and elevator quadrant 
support bracket. The FAA is not requiring the repetitive inspections of 
the control column lower sub-assembly, lower horizontal torque tube, 
and top and bottom channels of the pulley bracket assembly, and the 
modifications that terminate those inspections, because those actions 
are addressed by AD 69-05-01 R2, Amendment 39-3824 (Docket No. 79-EA-
63; 45 FR 45258, July 3, 1980); and AD 69-8-12 R1, Amendment 39-867 
(Docket No. 69-EA-133; 34 FR 18226, November 14, 1969).

Costs of Compliance

    The FAA estimates that this AD affects 133 airplanes of U.S. 
registry.
    The FAA estimates the following costs to comply with this AD:

[[Page 30407]]



                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                 Cost per         Cost on U.S.
             Action                  Labor cost           Parts cost             airplane          operators
----------------------------------------------------------------------------------------------------------------
Elevator quadrant and support    0.5 work-hour x    Not Applicable........  $42.50 per         $5,652.50 (for
 bracket visual inspection.       $85 per hour =                             inspection cycle.  the affected 133
                                  $42.50.                                                       airplanes) per
                                                                                                inspection
                                                                                                cycle.
Fluorescent penetrant            1 work-hour x $85  Not Applicable........  $85..............  $10,795 (for the
 inspection of the elevator       per hour = $85.                                               affected 127
 quadrant support bracket.                                                                      airplanes).
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any repairs or 
replacements that would be required based on the results of the 
inspections. The FAA has no way of determining the number of airplanes 
that might need these repairs/replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost       airplane
----------------------------------------------------------------------------------------------------------------
Replacement of elevator quadrant..............  1.5 work-hours x $85 per hour =             $825         $952.50
                                                 $127.50.
Fluorescent penetrant inspection of the         1 work-hour x $85 per hour = $85  Not Applicable              85
 elevator quadrant support bracket.
Replacement of elevator quadrant support        2 work-hours x $85 per hour =                485             655
 bracket.                                        $170.
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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

    The FAA has determined that 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:
0
a. Removing Airworthiness Directive 89-24-06 R1, Amendment 39-6670 
(Docket No. 89-CE-29-AD; 55 FR 29347, July 19, 1990); and
0
b. Adding the following new airworthiness directive:

2022-10-07 Viking Air Limited (Type Certificate Previously Held by 
Bombardier, Inc. and de Havilland, Inc.): Amendment 39-22045; Docket 
No. FAA-2022-0099; Project Identifier 2019-CE-019-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective June 23, 2022.

(b) Affected ADs

    This AD replaces AD 89-24-06 R1, Amendment 39-6670 (Docket No. 
89-CE-29-AD; 55 FR 29347, July 19, 1990) (AD 89-24-06 R1).

(c) Applicability

    This AD applies to Viking Air Limited (Type Certificate 
previously held by Bombardier, Inc. and de Havilland, Inc.) Model 
DHC-6-1, DHC-6-100, DHC-6-200, DHC-6-300, and DHC-6-400 airplanes, 
all serial numbers, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 2700, Flight Control 
System.

(e) Unsafe Condition

    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 damage to the 
flight control system. The FAA is issuing this AD to prevent failure 
of the flight control system. The unsafe condition, if not 
addressed, could result in loss of control of the airplane.

(f) Compliance

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

(g) Elevator Quadrant and Support Brackets: Inspections, Replacements, 
and Modifications

    (1) Visually inspect the elevator quadrant for indications of 
distortion (warping, buckling, or score marks) by following 
paragraphs III.A.2.(a) and III.A.2.(b) of the Accomplishment 
Instructions in Viking DHC-6 (Twin Otter) Service Bulletin 6-511, 
Revision A, dated June 22, 1990 (DHC-6 SB 6-511, Revision A) at the 
following applicable compliance times:
    (i) For Model DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 
airplanes, before further flight after the effective date of

[[Page 30408]]

this AD or within 400 hours time-in-service (TIS) after the last 
inspection required by AD 89-24-06 R1, whichever occurs later, and 
thereafter at intervals not to exceed 400 hours TIS; or
    (ii) For Model DHC-6-400 airplanes, before further flight after 
the effective date of this AD and thereafter at intervals not to 
exceed 400 hours TIS.
    Note 1 to paragraph (g)(1): The elevator quadrant may be 
identified as part number (P/N) C6CFM1138-27 (Pre Mod 6/1394), P/N 
C6CFM1450-27 (Post Mod 6/1394 or production cut-in (PCI) serial 
number (S/N) 331, Pre Mod 6/1678), or P/N C6CFM1450-29 (Post Mod 6/
1678 or PCI S/N 602), and is referred to as assembly P/N C6CF1137-1, 
-3, -5, or -7.
    (2) If any indication of distortion is found on the elevator 
quadrant during any inspection required by paragraph (g)(1) of this 
AD, before further flight, replace the elevator quadrant with a 
serviceable part and inspect the elevator quadrant support bracket 
assembly for cracks by following paragraphs III.B.1. through 
III.B.4.(b) of the Accomplishment Instructions in DHC-6 SB 6-511, 
Revision A. This AD requires that you do a fluorescent penetrant 
inspection as the type of required dye penetrant inspection. If a 
crack is found in the elevator quadrant support bracket, before 
further flight, replace with a serviceable part by following 
paragraphs III.B.5 through III.B.12 of the Accomplishment 
Instructions in DHC-6 SB 6-511, Revision A.
    (3) For Model DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 
airplanes: Within 400 hours TIS after the effective date of this AD, 
unless already done within the preceding 12 months before the 
effective date of this AD, inspect the elevator quadrant support 
bracket assembly for cracks by following paragraphs III.B.1. through 
III.B.4.(b) of the Accomplishment Instructions in DHC-6 SB 6-511, 
Revision A. This AD requires that you do a fluorescent penetrant 
inspection as the type of required dye penetrant inspection. If a 
crack is found in the elevator quadrant support bracket, before 
further flight, replace with a serviceable part by following 
paragraphs III.B.5 through III.B.12 of the Accomplishment 
Instructions in DHC-6 SB 6-511, Revision A.

(h) Credit for Previous Actions

    (1) For Model DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 
airplanes: This paragraph provides credit for the inspection 
required by paragraph (g)(1) of this AD if you performed the 
inspection before the effective date of this AD using paragraph 
(a)(1) of AD 89-24-06 R1.
    (2) For Model DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 
airplanes: This paragraph provides credit for the fluorescent 
penetrant inspection and subsequent replacement of the elevator 
quadrant support bracket due to a crack found from the fluorescent 
penetrant inspection required by paragraph (g)(2) of this AD if 
performed before the effective date of this AD using paragraphs 
(a)(3) and (4) of AD 89-24-06 R1.

(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 Darren Gassetto, 
Aviation Safety Engineer, New York ACO Branch, FAA, 1600 Stewart 
Avenue, Suite 410, Westbury, NY 11590; phone: (516) 228-7323; email: 
[email protected].
    (2) Refer to Transport Canada AD CF-1972-06R5, dated June 22, 
2018, for more information. You may examine the Transport Canada AD 
at https://www.regulations.gov by searching for and locating Docket 
No. FAA-2022-0099.

(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 6-511, Revision 
A, dated June 22, 1990.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact 
Viking Air Ltd., 1959 de Havilland Way, Sidney British Columbia, 
Canada V8L 5V5; phone: (800) 663-8444; email: 
[email protected]; website: https://www.vikingair.com.
    (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 May 5, 2022.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2022-10758 Filed 5-18-22; 8:45 am]
BILLING CODE 4910-13-P


