DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2022-0814; Project Identifier AD-2022-00205-A]
Airworthiness Directives; Viking Air Limited (Type Certificate
Previously Held by Bombardier Inc. and de Havilland 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 Viking Air Limited (type certificate previously held by Bombardier
Inc. and de Havilland Inc.) Model DHC-2 Mk. I airplanes with
Supplemental Type Certificate (STC) No. SA01324CH installed. This
proposed AD was prompted by a report of damage in the main wing spar.
This proposed AD would require inspecting the wing structure for damage
(drill starts, corrosion, cracks, and improperly installed fasteners),
repairing damage and reporting the inspection results if
necessary. 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 22, 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 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 Wipaire,
Inc., 1700 Henry Avenue, South Saint Paul, MN 55075; phone: (651) 414-
4460; email: firstname.lastname@example.org; website: www.wipaire.com. You may view
this service information at the Airworthiness Products Section,
Operational Safety Branch, FAA, 901 Locust, Kansas City, MO 64106. For
information on the availability of this material at the FAA, call (817)
Examining the AD Docket
You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2022-0814; 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: Dirk Dodge, Aviation Safety Engineer,
Chicago ACO Branch, FAA, 2300 E. Devon Avenue, Des Plaines, IL 60018;
phone: (847) 294-7135; email: Dirk.Dodge@faa.gov.
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-2022-0814; Project Identifier
AD-2022-00205-A" 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
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 Dirk
Dodge, Aviation Safety Engineer, Chicago ACO Branch, FAA, 2300 E Devon
Avenue, Des Plaines, IL 60018. Any commentary that the FAA receives
which is not specifically designated as CBI will be placed in the
public docket for this rulemaking.
The FAA received a report that during an annual inspection of a
Viking Air Limited Model DHC-2 Mk. I airplane, a gap was noted between
the doubler and wing near station 42.5, requiring partial removal of
the doubler and removal of the sealant between the doubler and the wing
skin. Further inspection of the internal wing structure of that area
with a borescope found damage in the forward spar caused by a drill
during initial installation of the doubler. The doubler was installed
as part of Wipaire, Inc., STC No. SA01324CH. Inspection of the rest of
the operator's fleet of airplanes with STC No. SA01324CH installed
found a total of 6 out of 14 wings with drill start damage in the same
area. Later inspections on these same airplanes on the outboard end of
the doubler installation revealed improperly installed fasteners. As
only a small fraction of the affected fleet has been inspected, the
possible extent of damage in the field is unknown. Accordingly, the FAA
determined that in addition to inspecting for drill starts and
improperly installed fasteners, inspecting for corrosion and cracks is
necessary. Damage of the main structural members of the wing could
adversely affect the structural integrity of the airplane and could
result in loss of control of the airplane.
The FAA is issuing this NPRM after determining that the unsafe
condition described previously is likely to exist or develop on other
products of the same type design.
Related Service Information
The FAA reviewed a Wipaire, Inc., letter, dated September 7, 2021.
This letter requests that operators inspect the front wing spar (strap)
and front (forward) spar aft flange for drill holes due to the
installation of the top wing strap installed using Wipaire, Inc.,
Drawing 5D1-790, which is an attachment to the letter. This letter also
requests reporting all findings of damage to Wipaire, Inc.
Proposed AD Requirements in This NPRM
This proposed AD would require inspecting the wing structure (spar
cap, spar flange, and stringers) for damage (drill starts, corrosion,
cracks, and improperly installed fasteners), repairing damage if
necessary, and reporting certain inspection results.
Differences Between This Proposed AD and the Service Information
The Wipaire, Inc., letter, dated September 7, 2021, specifies
inspecting the front spar and front spar aft flange between wing
stations 42.5 and 56. This proposed AD would require inspecting all
airplane structure under the installed doubler between wing stations
30.26 and 126.36.
Impact on Intrastate Aviation in Alaska
Airplanes modified by Wipaire, Inc., STC No. SA01324CH are often
used to transport cargo and supplies to remote areas of Alaska. The FAA
estimates that roughly half of the U.S.-registered airplanes modified
by STC No. SA01324CH are operating in Alaska. Since damage to the main
structural members of the wing could result in loss of the airplane
wing and therefore, loss of control of the airplane, the FAA has
determined that the need to correct the unsafe conditions outweighs any
impact on aviation in Alaska.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect 96 airplanes of U.S. registry.
The FAA estimates the following costs to comply with this proposed AD:
COST PER AIRPLANE
COST ON U.S. OPERATORS
6 work-hours x $85 per hour = $510
The FAA estimates the following costs to do any necessary repairs
that would be required based on the results of the proposed inspection.
The agency has no way of determining the number of airplanes that might
need these repairs.
COST PER AIRPLANE
100 work-hours x $85 per hour = $8,500
Report inspection results
1 work-hour x $85 per hour = $85
Paperwork Reduction Act
A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to a penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a current valid OMB Control Number. The OMB
Control Number for this information collection is 2120-0056. Public
reporting for this collection of information is estimated to take
approximately 1 hour per response, including the time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the
collection of information. All responses to this collection of
information are mandatory. Send comments regarding this burden estimate
or any other aspect of this collection of information, including
suggestions for reducing this burden, to: Information Collection
Clearance Officer, Federal Aviation Administration, 10101 Hillwood
Parkway, Fort Worth, TX 76177-1524.
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.
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, and
(2) 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
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
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]
2. The FAA amends Sec. 39.13 by adding the following new airworthiness