Discussion
We issued a supplemental notice of proposed rulemaking (SNPRM) to amend 14 CFR part 39 by adding an AD that would apply to all Viking Air Limited Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. The SNPRM published in the Federal Register on May 7, 2018 (83 FR 19983). We preceded the SNPRM with a notice of proposed rulemaking (NPRM) that published in the Federal Register on September 8, 2017 (82 FR 42489). The NPRM proposed to require inspecting the wing rear spar and flap/aileron support brackets within 400 hours time-in-service (TIS) and reporting the results to the manufacturer. The NPRM was based on mandatory continuing airworthiness information (MCAI) originated by Transport Canada, the aviation authority for Canada. The MCAI states:
It was reported that a crack was found in the wing rear spar web, part number C2W1007, at wing station 123.5 where the flap outboard hinge is attached. An aileron hinge bracket hasalso been found cracked. Viking Air Ltd. analysis shows that similar cracks may develop on the wing rear spar web and flap/aileron hinge arm support brackets at the other flap/aileron hinge attachment locations.
Undetected cracking of the wing rear spar or flap/aileron hinge bracket may lead to the failure of the component with consequent loss of aeroplane control.
The MCAI requires inspecting the left-hand and right-hand wing rear spar and the flap/aileron hinge air support brackets for cracks, damage, or discrepancies and repairing or replacing any parts with cracks, damage, or discrepancies. The MCAI can be found in the AD docket on the internet at https://www.regulations.gov/document?D=FAA-2017-0867-0002.
The SNPRM proposed to revise the compliance times to require the inspections within 400 hours TIS or 6 months, whichever occurs first, to match the compliance times in the MCAI.
Comments
We gave the public the opportunity to participate in developing this AD. We received no comments on the SNPRM or on the determination of the cost to the public.
Conclusion
We reviewed the relevant data, considered the comment received, and determined that air safety and the public interest require adopting this AD as proposed except for minor editorial changes. We have determined that these minor changes:
[Agr]re consistent with the intent that was proposed in the SNPRM for correcting the unsafe condition; and
Do not add any additional burden upon the public than was already proposed in the SNPRM.
We also determined that these changes will not increase the economic burden on any operator or increase the scope of this AD.
Related Service Information Under 1 CFR Part 51
Viking Air Limited has issued Viking DHC-2 Beaver Service Bulletin Number: V2/0009, Revision A, dated February 10, 2017. The service information describes procedures for inspecting the left-hand and right-hand wing rear spars, the flap/aileron hinge brackets,and the exterior store support bracket for cracks, damage, and discrepancies. The service information also specifies repairing or replacing any parts that have cracks, damage, or discrepancies. 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.
Interim Action
We consider this AD interim action. The inspection report required by this AD allows us to obtain better information into the nature, cause, and extent of the damage to the wing rear spars and flap/aileron hinge arm support brackets and to develop final action to address the unsafe condition. After evaluating the inspection results, we may consider further rulemaking.
Costs of Compliance
We estimate that this AD will affect 140 products of U.S. registry. We also estimate that it will take about 11 work-hours per product to comply with the basic inspection requirements ofthis AD. The average labor rate is $85 per work-hour.
Based on these figures, we estimate the basic cost of this AD on U.S. operators to be $130,900, or $935 per product.
Reporting the inspection findings would require about 5 minutes, for a cost of $7 per airplane and $980 for the U.S. operator fleet.
In addition, the following is an estimate of possible necessary follow-on replacement actions. We have no way of determining the number of products that may need these actions.
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Number of work-
Part No. Left-hand (LH) or right- Description Number per Parts cost hours to
hand (RH) wing airplane replace -------------------------------------------------------------------------------------------------------------------------------------------------------- C2W123A.................................. Both (one per wing)........ Hinge bracket LH inboard (flap)/ 2 \2\ 288 \2\ 12
RH outboard (aileron). C2W124A.................................. Both (one per wing)........ Hinge bracket RH inboard (flap)/ 2 \2\ 288 \2\ 12
LH outboard (aileron). C2W143................................... Both (four per wing)....... Hinge bracket, flap and aileron 8 \3\ 271 \3\ 12
(common part--multiple wing
stations (WS)). C2W143A (Agricultural Option)............ Both (one per wing)........ Agricultural (optional \1\ 2 \2\ 271 \2\ 12
configuration)--hinge bracket,
support arm (IPC PSM 1-2-4
Figure 128, Item 15). C2W63.................................... LH......................... Inboard spar, rear spar......... .............. 27760
[[Page 48365]]
C2W64.................................... RH......................... Inboard spar, rear spar......... .............. 277 60 C2W155................................... Both (one per wing)........ Intermediate spar............... 2 \2\ 563 \2\ 60 C2W65A................................... LH......................... Spar WS 89.16 to WS 170.16...... * 1 835 60 C2W66A................................... RH......................... Spar WS 89.16 to WS 170.16...... * 1 835 60 C2W67A................................... LH......................... Outboard spar, WS 170.16 to WS * 1 835 60
245.75. C2W68A................................... RH......................... Outboard spar, WS 170.16 to WS * 1 835 60
245.75. --------------------------------------------------------------------------------------------------------------------------------------------------------
* To replace any wing spar section takes 60 work-hours. To replace all four wing spar sections per wing takes 240 work-hours.
\1\ (If applies). \2\ For both. \3\ For all eight.
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 currently 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 be approximately 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, 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.
We are 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.
This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to small airplanes, gliders, balloons, airships, domestic business jet transport airplanes, and associated appliances to the Director of the Policy and Innovation Division.
Regulatory Findings
We 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 this AD:
(1) Is not a ``significant regulatory action'' under Executive Order 12866,
(2) Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in Alaska, and
(4) 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.
Examining the AD Docket
You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017- 0867; 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, the SNPRM, the regulatory evaluation, any comments received, and other information. The street address for Docket Operations (telephone (800) 647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.