[Federal Register Volume 73, Number 62 (Monday, March 31, 2008)]
[Proposed Rules]
[Pages 16779-16782]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-6468]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0367; Directorate Identifier 2007-CE-089-AD]
RIN 2120-AA64


Airworthiness Directives; Viking Air Limited Models DHC-6-1, DHC-
6-100, DHC-6-200, and DHC-6-300 Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
products listed above. This proposed AD results from 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:

    Service experience indicates that as aircraft become older, they 
are more likely to exhibit indications of corrosion.

Additionally, the FAA has reviewed the service experience and finds 
this action to be necessary based upon that service experience. The 
proposed AD would require actions that are intended to address the 
unsafe condition described in the MCAI.

DATES: We must receive comments on this proposed AD by April 30, 2008.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.

[[Page 16780]]

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone (800) 647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Richard Beckwith, Aerospace Engineer, 
FAA, New York Aircraft Certification Office,1600 Stewart Avenue, Suite 
410, Westbury, New York 11590; telephone: (516) 228-7302; fax: (516) 
568-2716.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0367; 
Directorate Identifier 2007-CE-089-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    Transport Canada, which is the aviation authority for Canada, has 
issued AD No. CF-94-12R1, dated April 13, 1999; and AD No. CF-99-11, 
dated May 28, 1999 (referred to after this as ``the MCAI''), to correct 
an unsafe condition for the specified products. The MCAI states:

    Service experience indicates that as aircraft become older, they 
are more likely to exhibit indications of corrosion. Transport 
Canada, in conjunction with other airworthiness authorities, has 
committed itself to ensuring that additional maintenance programs 
for older aircraft are developed and implemented to minimize and 
control corrosive deterioration that could jeopardize airworthiness. 
Bombardier Inc., as manufacturer of the DHC-6 aircraft, has 
developed a Corrosion Prevention and Control Program which 
identifies specific areas that must be inspected to ensure the 
structural integrity of the DHC-6 fleet.

Additionally, the FAA has reviewed the service experience of the Viking 
Air Limited Models DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-300 
airplanes and finds this action to be necessary based upon that service 
experience.
    The MCAI requires that you do the corrosion tasks required by the 
corrosion prevention and control program. You may obtain further 
information by examining the MCAI in the AD docket.

Relevant Service Information

    Viking Air Limited has issued DHC-6 Twin Otter (Series 100/200/300) 
Corrosion Prevention and Control Manual PSM 1-6-5, Revision 3, dated 
January 15, 2007; Viking Temporary Revision, C57-10-18 (TR 2-2), dated 
December 19, 2007; Viking Temporary Revision, Part 3, Supplement 1 (TR 
3-2), dated December 19, 2007; Viking Temporary Revision, Part 3, 
Supplement 1 (TR 3-3), dated December 19, 2007; and Viking Temporary 
Revision, Part 3, Supplement 1, (TR 3-4), dated December 19, 2007. The 
actions described in this service information are intended to correct 
the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of the Proposed AD

    This product has been approved by the aviation authority of another 
country, and is approved for operation in the United States. Pursuant 
to our bilateral agreement with this State of Design Authority, they 
have notified us of the unsafe condition described in the MCAI and 
service information referenced above together with the fact that the 
FAA has reviewed the service experience and finds this action to be 
necessary based upon that service experience. We are proposing this AD 
because we evaluated all information and determined the unsafe 
condition exists and is likely to exist or develop on other products of 
the same type design.

Differences Between This Proposed AD and the MCAI or Service 
Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use different words from those in the MCAI to ensure the 
AD is clear for U.S. operators and is enforceable. In making these 
changes, we do not intend to differ substantively from the information 
provided in the MCAI and related service information.
    We might also have proposed different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
highlighted in a NOTE within the proposed AD.

Costs of Compliance

    We estimate that this proposed AD would affect about 162 products 
of U.S. registry. We also estimate that it would take about 40 work-
hours per product to comply with the basic requirements of this 
proposed AD. The average labor rate is $80 per work-hour.
    Based on these figures, we estimate the cost of the proposed AD on 
U.S. operators to be $518,400, or $3,200 per product.

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.

Regulatory Findings

    We 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. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979); 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.

[[Page 16781]]

    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, 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

    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 AD:

Viking Air Limited: Docket No. FAA-2008-0367; Directorate Identifier 
2007-CE-089-AD.

Comments Due Date

    (a) We must receive comments by April 30, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Models DHC-6-1, DHC-6-100, DHC-6-200, and 
DHC-6-300 airplanes, serial numbers (SNs) 001 through 844, 
certificated in any category.

Subject

    (d) Air Transport Association of America (ATA) Code 51: 
Structures.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:

    Service experience indicates that as aircraft become older, they 
are more likely to exhibit indications of corrosion. Transport 
Canada, in conjunction with other airworthiness authorities, has 
committed itself to ensuring that additional maintenance programs 
for older aircraft are developed and implemented to minimize and 
control corrosive deterioration that could jeopardize airworthiness. 
Bombardier Inc., as manufacturer of the DHC-6 aircraft, has 
developed a Corrosion Prevention and Control Program which 
identifies specific areas that must be inspected to ensure the 
structural integrity of the DHC-6 fleet.

Additionally, the FAA has reviewed the service experience of the 
Viking Air Limited Models DHC-6-1, DHC-6-100, DHC-6-200, and DHC-6-
300 airplanes and finds this action to be necessary based upon that 
service experience. The MCAI requires that you do the corrosion 
tasks (CTs) required by the corrosion prevention and control 
program.

Actions and Compliance

    (f) Unless already done, do the following actions:
    (1) Within the next 90 days after the effective date of this AD, 
develop a schedule for doing the initial and repeat CTs required in 
paragraph (f)(2) and (f)(3) of this AD.
    (2) Initially, do all of the seven basic CTs defined at 
paragraph 3.0 of Part 3 of DHC-6 Twin Otter (Series 100/200/300) 
Corrosion Prevention and Control Manual PSM 1-6-5, Revision 3, dated 
January 15, 2007; and the temporary revisions listed in Table 1, 
Viking Temporary Revisions, of this AD:

                  Table 1.--Viking Temporary Revisions
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                     Temporary revision no. and date
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(i) Viking Temporary Revision, C57-10-18 (TR 2-2), dated December 19,
 2007.
(ii) Viking Temporary Revision, Part 3, Supplement 1 (TR 3-2), dated
 December 19, 2007.
(iii) Viking Temporary Revision, Part 3, Supplement 1 (TR 3-3), dated
 December 19, 2007.
(iv) Viking Temporary Revision, Part 3, Supplement 1, (TR 3-4), dated
 December 19, 2007.
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Determine corrosion level following the definitions contained in the 
introduction section of DHC-6 Twin Otter (Series 100/200/300) 
Corrosion Prevention and Control Manual PSM 1-6-5, Revision 3, dated 
January 15, 2007. The initial accomplishment deadlines are specified 
in Table 2, Initial Accomplishment Deadline, of this AD:

                Table 2.--Initial Accomplishment Deadline
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                                         Initial accomplishment deadline
   Applicable airplane serial numbers    for all airplanes in applicable
                                                    S/N range
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(i) 001 through 199....................  15 months after the effective
                                          date of this AD.
(ii) 200 through 439...................  27 months after the effective
                                          date of this AD.
(iii) 440 through 659..................  51 months after the effective
                                          date of this AD.
(iv) 660 through 844...................  63 months after the effective
                                          date of this AD.
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    (3) After the initial completion of each CT, repeat each CT at 
the repeat interval (R) specified in the manual. Determine corrosion 
level following the definitions contained in the introduction 
section of DHC-6 Twin Otter (Series 100/200/300) Corrosion 
Prevention and Control Manual PSM 1-6-5, Revision 3, dated January 
15, 2007.
    (4) If any corrosion is found during any action required by this 
AD, before further flight, address corrosion following paragraph 4.0 
of Part 3 of DHC-6 Twin Otter (Series 100/200/300) Corrosion 
Prevention and Control Manual PSM 1-6-5, Revision 3, dated January 
15, 2007. All repairs are to be done following a method approved by 
the Manager, New York Aircraft Certification Office or Transport 
Canada Civil Aviation (or its delegated agent).
    (5) Within 21 days after the finding of Level 3 corrosion, 
submit a plan to the FAA to identify a schedule for accomplishing 
the applicable CTs on the remainder of the airplanes in the 
operator's fleet that are subject to this AD or data substantiating 
that the Level 3 corrosion that was found is an isolated case. The 
FAA may impose a schedule other than proposed in the plan upon 
finding that a change to the schedule is needed to ensure that any 
other Level 3 corrosion is detected in a timely manner. For the 
purposes of this paragraph, the FAA is defined as the cognizant 
principal maintenance inspector (PMI) for operators that are 
assigned a PMI (e.g., part 121, 125, and 135 operators) and the 
cognizant flight standards district office for other operators 
(e.g., part 91 operators).
    (6) If any Level 3 corrosion is found while doing any action 
required by this AD, within 21 days after the finding of Level 3 
corrosion, report the finding on the form in Figure 1 of this AD and 
send it to Viking Air Limited, VP Engineering, 9574 Hampden Road, 
Sidney, British Columbia, Canada V8L 5V5.
    (7) Incorporation of the initial and repeat CTs into your FAA-
approved maintenance program constitutes terminating action for this 
AD. If this AD is terminated in this way, then the maintenance 
program must be in accordance with this AD.

FAA AD Differences

    Note: This AD differs from the MCAI and/or service information 
as follows: No differences.

Other FAA AD Provisions

    (g) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, New 
York Aircraft Certification Office (ACO), FAA, has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19. Send information to ATTN: Richard Beckwith, 
Aerospace Engineer, FAA, New York ACO, 1600 Stewart Avenue, Suite 
410, Westbury, New York 11590; telephone: (516) 228-7302; fax: (516) 
568-2716. Before using any approved AMOC on any airplane to which 
the AMOC applies, notify your

[[Page 16782]]

appropriate PMI in the FAA Flight Standards District Office (FSDO), 
or lacking a PMI, your local FSDO.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act (44 
U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has 
approved the information collection requirements and has assigned 
OMB Control Number 2120-0056.

                        Docket No. FAA-2008-0367
                            Inspection Report
               [Report only if you find level 3 corrosion]
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1. Operator:                                2. Telephone:
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3. Airplane Model Number:                   4. Airplane Serial Number:
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5. Airplane Tail Number:                    6. Date of Inspection:
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7. Corrosion Task:
 
 
 
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8. Description & Specific Location of Findings:
 
 
 
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9. Additional Comments of Owner/Operator:
 
 
 
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Send to:
 
Viking Air Limited
VP Engineering
9574 Hampden Road
Sidney, British Columbia, Canada
V8L 5V5
 
Telephone: 250.656.7227
Fax: 250.656.9702
 
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                                Figure 1.
 

Related Information

    (h) Refer to MCAI Transport Canada AD No. CF-94-12R1, dated 
April 13, 1999; and Transport Canada AD No. CF-99-11, dated May 28, 
1999; and DHC-6 Twin Otter (Series 100/200/300) Corrosion Prevention 
and Control Manual PSM 1-6-5, Revision 3, dated January 15, 2007; 
and the temporary revisions listed in Table 1--Viking Temporary 
Revisions, of this AD, for related information.

David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E8-6468 Filed 3-28-08; 8:45 am]
BILLING CODE 4910-13-P