[Federal Register Volume 88, Number 68 (Monday, April 10, 2023)]
[Rules and Regulations]
[Pages 21096-21097]
[FR Doc No: 2023-07202]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 71

[Docket No. FAA-2023-0036; Airspace Docket No. 23-AGL-5]
RIN 2120-AA66

Amendment of Class E Airspace; Rantoul, IL

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: This action amends the Class E airspace at Rantoul, IL. This
action is due to an airspace review conducted as part of the
decommissioning of the Danville very high frequency omnidirectional
range (VOR) as part of the VOR Minimum Operating Network (MON) Program.
The name and geographic coordinates of the airport are also being
updated to coincide with the FAA's aeronautical database.

DATES: Effective 0901 UTC, June 15, 2023. The Director of the Federal
Register approves this incorporation by reference action under 1 CFR
part 51, subject to the annual revision of FAA Order JO 7400.11 and
publication of conforming amendments.

ADDRESSES: A copy of the Notice of Proposed Rulemaking (NPRM), all
comments received, this final rule, and all background material may be
viewed online at www.regulations.gov using the FAA Docket number.
Electronic retrieval help and guidelines are available on the website.
It is available 24 hours each day, 365 days each year.
    FAA Order JO 7400.11G, Airspace Designations and Reporting Points,
and subsequent amendments can be viewed online at www.faa.gov/air_traffic/publications/. You may also contact the Rules and
Regulations Group, Office of Policy, Federal Aviation Administration,
800 Independence Avenue SW, Washington, DC 20591; telephone: (202) 267-
8783.

FOR FURTHER INFORMATION CONTACT: Jeffrey Claypool, Federal Aviation
Administration, Operations Support Group, Central Service Center, 10101
Hillwood Parkway, Fort Worth, TX 76177; telephone<PHONE_NUMBER>.

SUPPLEMENTARY INFORMATION:

Authority for This Rulemaking

    The FAA's authority to issue rules regarding aviation safety is
found in Title 49 of the United States Code. 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. This rulemaking is promulgated under the authority described
in Subtitle VII, Part A, Subpart I, Section 40103. Under that section,
the FAA is charged with prescribing regulations to assign the use of
airspace necessary to ensure the safety of aircraft and the efficient
use of airspace. This regulation is within the scope of that authority
as it amends the Class E airspace extending upward from 700 feet above
the surface at Rantoul National Aviation Center-Frank Elliot Field,
Rantoul, IL, to support instrument flight rule operations at this
airport.

History

    The FAA published a notice of proposed rulemaking (NPRM) for Docket
No. FAA-2023-0036 in the Federal Register (88 FR 2870; January 18,
2023) amending the Class E airspace at Rantoul, IL. Interested parties
were invited to participate in this rulemaking effort by submitting
written comments on the proposal to the FAA. No comments were received.

Differences From the NPRM

    Subsequent to publication, the FAA discovered that the geographic
coordinates required updating. This update is administrative and does
not impact the airspace as proposed.

Incorporation by Reference

    Class E airspace designations are published in paragraph 6005 of
FAA Order JO 7400.11, Airspace Designations and Reporting Points, which
is incorporated by reference in 14 CFR 71.1 on an annual basis. This
document amends the current version of that order, FAA Order JO
7400.11G, dated August 19, 2022, and effective September 15, 2022. FAA
Order Jo 7400.11G is publicly available as listed in the ADDRESSES
section of this document. These amendments will be published in the
next update to FAA Order JO 7400.11.
    FAA Order JO 7400.11G lists Class A, B, C, D, and E airspace areas,
air traffic service routes, and reporting points.

The Rule

    This amendment to 14 CFR part 71 modifies the Class E airspace
extending upward from 700 feet above the surface to within a 6.8-mile
(increased from a 6.7-mile) radius of Rantoul National Aviation Center-
Frank Elliot Field, Rantoul, IL; removes the exclusion areas from the
airspace legal description as they are not required; and updates the
name (previously Rantoul National Aviation Center Airport) and
geographic coordinates of the airport to coincide with the FAA's
aeronautical database.

Regulatory Notices and Analyses

    The FAA has determined that this regulation only involves an
established body of technical regulations for which frequent and
routine amendments are necessary to keep them operationally current.
It, therefore: (1) is not a ``significant regulatory action'' under
Executive Order 12866; (2) is not a ``significant rule'' under DOT
Regulatory Policies and Procedures (44 FR 11034; February 26, 1979);
and (3) does not warrant preparation of a regulatory evaluation as the
anticipated impact is so minimal. Since this is a routine matter that
only affects air traffic procedures and air navigation, it is certified
that this rule, when promulgated, does not have a significant economic
impact on a substantial number of small entities under the criteria of
the Regulatory Flexibility Act.

Environmental Review

    The FAA has determined that this action qualifies for categorical
exclusion under the National Environmental Policy Act in accordance
with FAA Order 1050.1F, ``Environmental Impacts: Policies and
Procedures,'' paragraph 5-6.5.a. This airspace action is not expected
to cause any potentially significant environmental impacts, and no
extraordinary circumstances exist that warrant preparation of an
environmental assessment.

Lists of Subjects in 14 CFR 71

    Airspace, Incorporation by reference, Navigation (air).

The Amendment

    In consideration of the foregoing, the Federal Aviation
Administration amends 14 CFR part 71 as follows:

PART 71--DESIGNATION OF CLASS A, B, C, D, AND E AIRSPACE AREAS; AIR
TRAFFIC SERVICE ROUTES; AND REPORTING POINTS

0
1. The authority citation for 14 CFR part 71 continues to read as
follows:

    Authority: 49 U.S.C. 106(f), 106(g); 40103, 40113, 40120; E.O.
10854, 24 FR 9565, 3 CFR, 1959-1963 Comp., p. 389.

Sec.  71.1  [Amended]

0
2. The incorporation by reference in 14 CFR 71.1 of FAA Order JO
7400.11G, Airspace Designations and Reporting Points, dated August 19,
2022, and effective September 15, 2022, is amended as follows:

Paragraph 6005 Class E Airspace Areas Extending Upward From 700
Feet or More Above the Surface of the Earth.

* * * * *

AGL IL E5 Rantoul, IL [Amended]

Rantoul National Aviation Center-Frank Elliott Field, IL
    (Lat. 40[deg]17'37'' N, long. 88[deg]08'33'' W)

    That airspace extending upward from 700 feet above the surface
within a 6.8-mile radius of the Rantoul National Aviation Center-
Frank Elliott Field.

    Issued in Fort Worth, Texas, on April 3, 2023.
Martin A. Skinner,
Acting Manager, Operations Support Group, ATO Central Service Center.
[FR Doc. 2023-07202 Filed 4-7-23; 8:45 am]
BILLING CODE 4910-13-P


[Federal Register: June 8, 2010 (Volume 75, Number 109)]
[Rules and Regulations]
[Page 32253-32255]
[DOCID:fr08jn10-2]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0201; Directorate Identifier 2008-NE-47-AD;
Amendment 39-16314; AD 2010-11-09]
RIN 2120-AA64

Airworthiness Directives; Thielert Aircraft Engines GmbH (TAE)
Models TAE 125-01 and TAE 125-02-99 Reciprocating Engines Installed in,
but Not Limited to, Diamond Aircraft Industries Model DA 42 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the
products listed above. This AD results from mandatory continuing
airworthiness information (MCAI) issued 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:

    Engine in-flight shutdown incidents have been reported on
Diamond Aircraft Industries DA 42 airplanes equipped with TAE 125
engines. The investigations showed that it was mainly the result of
failure of the Proportional Pressure Reducing Valve (PPRV) (also
known as Propeller Control Valve) due to high vibrations. This
condition, if not corrected, could lead to further cases of engine
in-flight shutdown, possibly resulting in reduced control of the
aircraft.
    Since the release of European Aviation Safety Agency (EASA) AD
2008-0145, the engine gearbox has been identified as the primary
source of vibrations for the PPRV, and it has also been determined
that failure of the electrical connection to the PPRV could have
contributed to some power loss events or in-flight shutdowns.

We are issuing this AD to prevent engine in-flight shutdown, possibly
resulting in reduced control of the aircraft.

DATES: This AD becomes effective July 13, 2010. The Director of the
Federal Register approved the incorporation by reference of certain
publications listed in this AD as of July 13, 2010.

ADDRESSES: The Docket Operations office is located at Docket Management
Facility, U.S. Department of Transportation, 1200 New Jersey Avenue,
SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-
0001.

FOR FURTHER INFORMATION CONTACT: Tara Chaidez, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803; e-mail:
<EMAIL_ADDRESS>telephone<PHONE_NUMBER>; fax<PHONE_NUMBER>.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) and a supplemental
NPRM to amend 14 CFR part 39 to include an AD that would apply to the
specified products. That NPRM was published in the Federal Register on
April 17, 2009 (74 FR 17795) and that supplemental NPRM was published
in the Federal Register on February 23, 2010 (75 FR 7996). That
supplemental NPRM proposed to correct an unsafe condition for the
specified products. The MCAI states that:

    Engine in-flight shutdown incidents have been reported on
Diamond Aircraft Industries DA 42 airplanes equipped with TAE 125
engines. The investigations showed that it was mainly the result of
failure of the Proportional Pressure Reducing Valve (PPRV) (also
known as Propeller Control Valve) due to high vibrations. This
condition, if not corrected, could lead to further cases of engine
in-flight shutdown, possibly resulting in reduced control of the
aircraft.
    Since the release of European Aviation Safety Agency (EASA) AD
2008-0145, the engine gearbox has been identified as the primary
source of vibrations for the PPRV, and it has also been determined
that failure of the electrical connection to the PPRV could have
contributed to some power loss events or in-flight shutdowns.

Comments

    We gave the public the opportunity to participate in developing
this AD. We received no comments on the supplemental NPRM or on the
determination of the cost to the public.

Conclusion

    We reviewed the available data and determined that air safety and
the public interest require adopting the AD as proposed.

Differences Between This AD and the MCAI or Service Information

    We have reviewed the MCAIs and, in general, agree with their
substance. But we have found it necessary to not reference the second
paragraph of the unsafe condition from EASA AD 2009-0224. That sentence
stated that the problem has only manifested itself on those Thielert
engines installed on Diamond Aircraft Industries DA 42 aircraft. The
affected engines which require a PPRV could be used on other make and
model airplanes in the future.
    We also did not incorporate the February 28, 2010 compliance date
which is in EASA AD 2009-0193R1, or the January 31, 2010 compliance
date which is in EASA AD 2009-0224.

Costs of Compliance

    Based on the service information, we estimate that this AD will
affect about 300 TAE 125-01 and TAE 125-02-99 reciprocating engines
installed in Diamond Aircraft Industries Model DA 42 airplanes of U.S.
registry. We also estimate that it will take about 0.25 work-hour per
engine to replace a PPRV and install a vibration isolator to the
gearbox assembly. The average labor rate is $85 per work-hour. Required
parts will cost about $275 per product. Based on these figures, we
estimate the cost of the AD on U.S. operators to be $88,875.

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

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, the regulatory evaluation,
any comments received, and other information. The street address for
the Docket Operations office (phone<PHONE_NUMBER>) is provided 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.

Adoption of the Amendment

0
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 AD:

2010-11-09 Thielert Aircraft Engines GmbH: Amendment 39-16314.
Docket No. FAA-2009-0201; Directorate Identifier 2008-NE-47-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective July 13,
2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Thielert Aircraft Engines GmbH (TAE)
models TAE 125-01 and TAE 125-02-99 reciprocating engines designated
with part number (P/N) 05-7200-K000301 or 02-7200-1401R1. The
engines are installed on, but not limited to, Diamond Aircraft
Industries Model DA 42 airplanes.

Reason

    (d) Engine in-flight shutdown incidents have been reported on
Diamond Aircraft Industries DA 42 airplanes equipped with TAE 125
engines. The investigations showed that it was mainly the result of
failure of the Proportional Pressure Reducing Valve (PPRV) (also
known as Propeller Control Valve) due to high vibrations. This
condition, if not corrected, could lead to further cases of engine
in-flight shutdown, possibly resulting in reduced control of the
aircraft.
    Since the release of European Aviation Safety Agency (EASA) AD
2008-0145, the engine gearbox has been identified as the primary
source of vibrations for the PPRV, and it has also been determined
that failure of the electrical connection to the PPRV could have
contributed to some power loss events or in-flight shutdowns.

We are issuing this AD to prevent engine in-flight shutdown,
possibly resulting in reduced control of the aircraft.

Actions and Compliance

    (e) Unless already done, do the following actions:

TAE 125-02-99 Reciprocating Engines

    (1) For TAE 125-02-99 reciprocating engines with engine P/N 05-
7200-K000301, within 55 flight hours after the effective date of
this AD:
    (i) Replace the existing PPRV with PPRV, P/N 05-7212-E002801.
Use paragraphs A. through B. of Thielert Service Bulletin (SB) No.
TM TAE 125-1007 P1, Revision 2, dated April 29, 2009, to do the
replacement.
    (ii) Install a vibration isolator, P/N 05-7212-K022302, to the
gearbox assembly. Use paragraphs 1 through 20 of Thielert SB No. TM
TAE 125-1009 P1, Revision 3, dated October 14, 2009, to do the
installation.

Repetitive PPRV Replacements

    (2) Thereafter, within every 300 flight hours, replace the PPRV,
P/N 05-7212-E002801, with the same P/N PPRV.

TAE 125-01 Reciprocating Engines

    (3) For TAE 125-01 reciprocating engines with engine P/N 02-
7200-1401R1, within 55 flight hours after the effective date of this
AD:
    (i) Replace the existing PPRV with a PPRV, P/N NM-0000-0124501
or P/N 05-7212-K021401. Use paragraph 1 of Thielert SB No. TM TAE
125-0018, Revision 1, dated November 12, 2008, to do the
replacement.
    (ii) Inspect the electrical connectors of the PPRV and replace
the connectors if damaged, and install a vibration isolator, P/N 05-
7212-K023801, to the gearbox assembly. Use paragraphs 1 through 27
of Thielert SB No. TM TAE 125-0020, Revision 1, dated November 25,
2009, to do the inspection and installation.

Repetitive PPRV Replacements

    (4) Thereafter, within every 300 flight hours, replace the PPRV
with a PPRV, P/N NM-0000-0124501 or P/N 05-7212-K021401.

FAA Differences

    (f) We have found it necessary to not reference the second
paragraph of the unsafe condition from the MCAI EASA AD 2009-0224.
That sentence stated that the problem has only manifested itself on
those Thielert engines installed on Diamond Aircraft Industries DA
42 aircraft. The affected engines which require a PPRV could be used
on other make and model airplanes in the future.
    (g) We also did not reference the February 28, 2010 compliance
date, which is in EASA AD 2009-0193R1, or the January 31, 2010
compliance date which is in EASA AD 2009-0224.

Alternative Methods of Compliance (AMOCs)

    (h) The Manager, Engine Certification Office, FAA, has the
authority to approve AMOCs for this AD, if requested using the
procedures found in 14 CFR 39.19.

Related Information

    (i) Refer to EASA AD 2009-0224, dated October 20, 2009 (TAE 125-
02-99), and EASA AD 2009-0193R1, dated December 1, 2009 (TAE 125-
01), for related information.
    (j) Contact Tara Chaidez, Aerospace Engineer, Engine
Certification Office, FAA, Engine and Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; e-mail:
<EMAIL_ADDRESS>telephone<PHONE_NUMBER>; fax<PHONE_NUMBER>,
for more information about this AD.

Material Incorporated by Reference

    (k) You must use the service information specified in Table 1 of
this AD to do the actions required by this AD, unless the AD
specifies otherwise.
    (1) The Director of the Federal Register approved the
incorporation by reference of this service information under 5
U.S.C. 552(a) and 1 CFR part 51.
    (2) For service information identified in this AD, contact
Thielert Aircraft Engines GmbH, Platanenstrasse 14 D-09350,
Lichtenstein, Germany, telephone: +49-37204-696-0; fax: +49-37204-
696-2912; e-mail<EMAIL_ADDRESS>    (3) You may review copies at the FAA, New England Region, 12 New
England Executive Park, Burlington, MA; or at the National Archives
and Records Administration (NARA). For information on the
availability of this material at NARA, call<PHONE_NUMBER>, or go
to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

                                   Table 1--Material Incorporated by Reference
----------------------------------------------------------------------------------------------------------------
    Thielert Service Bulletin No.               Page              Revision                    Date
----------------------------------------------------------------------------------------------------------------
TM TAE 125-1007 P1..................  ALL....................               2  April 29, 2009.
    Total Pages: 4
TM TAE 125-1009 P1..................  ALL....................               3  October 14, 2009.
    Total Pages: 26
TM TAE 125-0018.....................  ALL....................               1  November 12, 2008.
    Total Pages: 2
TM TAE 125-0020, including Annexes A  ALL....................               1  November 25, 2009.
 and B.
    Total Pages: TM TAE 125-0020,
     42; Annex A, 3; Annex B, 4
----------------------------------------------------------------------------------------------------------------

    Issued in Burlington, Massachusetts, on May 19, 2010.
Tracy Murphy,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2010-12540 Filed 6-7-10; 8:45 am]
BILLING CODE 4910-13-P


[Federal Register: December 10, 2008 (Volume 73, Number 238)]
[Proposed Rules]
[Page 74999-75007]
[DOCID:fr10de08-16]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-23646; Directorate Identifier 2006-CE-005-AD]
RIN 2120-AA64

Airworthiness Directives; Air Tractor, Inc., Models AT-400, AT-
401, AT-401B, AT-402, AT-402A, and AT-402B Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to revise Airworthiness Directive (AD) 2006-08-08,
which applies to certain Air Tractor, Inc. (Air Tractor), Models AT-
400, AT-401, AT-401B, AT-402, AT-402A, and AT-402B airplanes. AD 2006-
08-08 currently requires you to repetitively eddy current inspect the
wing lower spar cap in order to reach the safe life and, for certain
Models AT-402A and AT-402B airplanes and those that incorporate or have
incorporated Marburger Enterprises, Inc. (Marburger), winglets, lowers
the safe life for the wing lower spar cap. Since we issued AD 2006-08-
08, we have received information to update inspection intervals for the
Models AT-401B, AT-402A, and AT-402B airplanes based on a revised
damage tolerance analysis. Consequently, this proposed AD would not
only retain the actions of AD 2006-08-08, but would reduce the number
of repetitive inspections for all affected Model AT-401B airplanes and
certain Models AT-402A and AT-402B airplanes. We are proposing this AD
to prevent fatigue cracks from occurring in the wing lower spar cap
before the originally established safe life is reached. Fatigue cracks
in the wing lower spar cap, if not detected and corrected, could result
in wing separation and loss of control of the airplane.

DATES: We must receive comments on this proposed AD by February 9,
2009.

ADDRESSES: Use one of the following addresses to comment on this
proposed AD:
     Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
     Fax:<PHONE_NUMBER>.
     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.
    For service information identified in this proposed AD, contact Air
Tractor, Inc., P.O. Box 485, Olney, Texas 76374; telephone: (940) 564-
5616; facsimile:<PHONE_NUMBER>; Internet: http://www.airtractor.com;
or Marburger Enterprises, Inc., 1227 Hillcourt, Williston, North Dakota
58801; telephone:<PHONE_NUMBER> or<PHONE_NUMBER>; facsimile: (701)
572-2602.

FOR FURTHER INFORMATION CONTACT: Direct all questions to:
--For airplanes that do not incorporate and never have incorporated
Marburger winglets: Rob Romero, Aerospace Engineer, FAA, Fort Worth
Airplane Certification Office, 2601 Meacham Boulevard, Fort Worth,
Texas 76193-0150; telephone:<PHONE_NUMBER>; facsimile:<PHONE_NUMBER>;
and
--For airplanes that incorporate or have incorporated Marburger
Enterprises, Inc., winglets: John Cecil, Aerospace Engineer, Los
Angeles Aircraft Certification Office, FAA, 3960 Paramount Boulevard,
Lakewood, California, 90712; telephone:<PHONE_NUMBER>; facsimile:
(562) 627-5210.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed under the ADDRESSES section. Include the docket number, ``FAA-
2006-23646; Directorate Identifier 2006-CE-005-AD'' at the beginning of
your comments. We specifically invite comments on the overall
regulatory, economic, environmental, and energy aspects of the proposed
AD. We will consider all comments received by the closing date and may
amend the proposed AD in light 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 concerning this proposed AD.

Discussion

    An Air Tractor Model AT-502A experienced an in-flight wing
separation. As a result, the FAA issued AD 2000-14-51 as an emergency
AD. That AD required the inspection of the wing lower spar cap for
cracks on Air Tractor Models AT-501, AT-502, and AT-502A airplanes and
modification or replacement of any cracked wing lower spar cap. Since
the release of that AD, the manufacturer has evaluated the AT-400, AT-
500, AT-600, and AT-800 series lower spar cap fatigue life.
    AD 2006-08-08 currently requires you to repetitively eddy current
inspect the wing lower spar cap for fatigue cracks in order to reach
the safe life and, for certain Models AT-402A and AT-402B airplanes and
those that incorporate or have incorporated Marburger winglets, lowers
the safe life for the wing lower spar cap.
    Since we issued AD 2006-08-08, we have received updated inspection
intervals for fatigue cracks for the Models AT-401B, AT-402A, and AT-
402B airplanes based on a revised damage tolerance analysis. Any
occurrence of fatigue cracks in the wing lower spar cap, if not
detected and corrected, could result in wing separation and loss of
control of the airplane.
    The following table contains AD actions that address the wing spar
safe life of the Air Tractor airplane fleet:

                                               Related AD Actions
----------------------------------------------------------------------------------------------------------------
                                          Affected Air Tractor Airplane
                 AD No.                               Model                             Issue date
----------------------------------------------------------------------------------------------------------------
2003-07-04.............................  AT-300, AT-400, AT-400A, AT-     March 25, 2003.
                                          401, AT-401B, AT-402, AT-402A,
                                          AT-402B, AT-501, AT-502, and
                                          AT-502B.
2006-08-08.............................  AT-400, AT-401, AT-401B, AT-     April 10, 2006.
                                          402, AT-402A, and AT-402B.
2006-08-09.............................  AT-802 and AT-802A.............  April 10, 2006.
2006-23-09.............................  AT-602.........................  October 26, 2006.
2006-24-10.............................  AT-501, AT-502, AT-502A, AT-     November 22, 2006.
                                          502B, and AT-503A.
2008-09-10.............................  AT-300, AT-301, AT-302, AT-400,  April 18, 2008.
                                          and AT-400A.
----------------------------------------------------------------------------------------------------------------

    You may view these Airworthiness Directives at the following
Internet Web site addresses: http://rgl.faa.gov or http://
www.gpoaccess.gov/fr/index.html.

Relevant Service Information

    We have reviewed this Snow Engineering Co. service information:
     Process Specification 197, page 1, revised June
4, 2002, pages 2 through 4, dated February 23, 2001, and page 5, dated
May 3, 2002;
     Drawing Number 21088, dated November 3, 2004; and
     Service Letter 202, page 3, dated October 16,
2000.
    Snow Engineering Co. has a licensing agreement with Air Tractor
that allows them to produce technical data to use for Air Tractor
products.
    The process specification and drawing include procedures for doing
the eddy-current inspection and replacing the spar caps and associated
hardware. The service letter provides information for installing access
panels, if not already installed.

FAA's Determination and Requirements of the Proposed AD

    We are proposing this AD because we evaluated all information and
determined the unsafe condition described previously is likely to exist
or develop on other products of the same type design. This proposed AD
would revise AD 2006-08-08 with a new AD that would not only retain the
actions AD 2006-08-8, but would reduce the number of repetitive
inspections for:
     All affected Model AT-401B airplanes;
     Model AT-402A airplanes, all serial numbers beginning with
0952; and
     Model AT-402B airplanes, all serial numbers beginning with
0966.
    This proposed AD would require you to use the service information
described previously to perform these actions.

Costs of Compliance

    We estimate that this AD affects 343 airplanes in the U.S.
registry.
    We estimate the following costs to do the inspection. We have no
way of determining the number of airplanes that may need repair or
modification as a result of any inspection:

----------------------------------------------------------------------------------------------------------------
                                                                                Total cost on U.S.
              Labor cost                      Parts cost        Total cost per airplane         operators
----------------------------------------------------------------------------------------------------------------
* $500 to $800.......................  Not Applicable.........  $500 to $800...........  $171,500 to
                                                                                $274,400.
----------------------------------------------------------------------------------------------------------------
* Eddy-current inspections are an estimated flat cost that includes labor and use of equipment.

    We estimate the following costs to do the modification. We have no
way of determining the number of airplanes that may need this
modification:

------------------------------------------------------------------------
                                                          Total cost per
               Labor cost                   Parts cost       airplane
------------------------------------------------------------------------
120 work-hours x $80 = $9,600...........         $11,500         $21,100
------------------------------------------------------------------------

    We estimate the following costs to do the replacement. We have no
way of determining the number of airplanes that may need this
replacement:

------------------------------------------------------------------------
                                                              Total cost
                  Labor cost                     Parts cost      per
                                                               airplane
------------------------------------------------------------------------
$16,500.......................................      $16,500     $33,000
------------------------------------------------------------------------
* The labor costs of the replacement are an estimated flat cost that
  includes labor and use of equipment.

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

Examining the AD Docket

    You may examine the AD docket that contains the proposed AD, the
regulatory evaluation, any comments received, and other information 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 Docket Office (telephone<PHONE_NUMBER>)
is located at the street address stated 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.

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 removing Airworthiness Directive
(AD) 2006-08-08, Amendment 39-14563 (71 FR 19986, April 19, 2006), and
adding the following new AD:

Air Tractor, Inc.: Docket No. FAA-2006-23646; Directorate Identifier
2006-CE-005-AD.

Comments Due Date

    (a) We must receive comments on this AD action by February 9,
2009.

Affected ADs

    (b) This AD revises AD 2006-08-08, Amendment 39-14563.

Applicability

    (c) This AD applies to certain Models AT-400, AT-401, AT-401B,
AT-402, AT-402A, and AT-402B airplanes that are certificated in any
category. Use paragraph (c)(1) of this AD for affected airplanes
that do not incorporate and never have incorporated Marburger
winglets. Use paragraph (c)(3) of this AD for airplanes that have
been modified to install lower spar caps, part number (P/N) 21058-1
and P/N 21058-2. Use paragraph (c)(4) of this AD for certain Models
AT-401, AT-401B, AT-402, AT-402A, and AT-402B airplanes that
incorporate or have incorporated Marburger winglets.
    (1) The following table applies to airplanes that do not
incorporate and never have incorporated Marburger winglets along
with the safe life (presented in hours time-in-service (TIS)) of the
wing lower spar cap for all affected airplane models and serial
numbers:

 Table 1--Safe Life for Airplanes That Do Not Incorporate and Never Have
                     Incorporated Marburger Winglets
------------------------------------------------------------------------
                                                            Wing lower
                                                           spar cap safe
             Model                     Serial Nos.         life  (hours
                                                               TIS)
------------------------------------------------------------------------
AT-400.........................  All beginning with 0416          13,300
AT-401.........................  0662 through 0951......          10,757
AT-401B........................  0952 through 1020,                6,948
                                  except 1015.
AT-401B........................  1015 and all beginning            7,777
                                  with 1021.
AT-402.........................  0694 through 0951......           7,440
AT-402A........................  0738 through 0951......           7,440
AT-402A........................  0952 through 1020......           2,000
AT-402A........................  All beginning with 1021           2,300
AT-402B........................  0966 through 1020,                2,000
                                  except 1015.
AT-402B........................  1015 and all beginning            2,300
                                  with 1021.
------------------------------------------------------------------------

    (2) If piston-powered aircraft have been converted to turbine
power, you must use the limits for the corresponding serial number
turbine-powered aircraft.
    (3) If you have an aircraft that has been modified by installing
lower spar caps, P/N 21058-1 and P/N 21058-2, you must use a wing
lower spar cap safe life of 9,800 hours TIS. No inspections are
required to reach this life.
    (i) Airplanes that have been modified with replacement spar
caps, P/N 21058-1 and P/N 21058-2, are not eligible to have
Supplemental Type Certificate (STC) No. SA00490LA, Marburger
winglets, installed.
    (ii) If your airplane currently has spar caps, P/N 21058-1 and
P/N 21058-2, and winglets installed, then you must remove the
winglets before further flight and you must contact the FAA at the
address in paragraph (m)(1) of this AD for a new safe life.
    (iii) Installation of Marburger winglets on airplanes that have
been modified with replacement spar caps, P/N 21058-1 and P/N 21058-
2, will require additional fatigue data substantiating an
appropriate safe-life. If you have replacement spar caps and wish to
install winglets, you must contact the FAA at the address in
paragraph (m)(2) of this AD for additional information.
    (4) The following table applies to airplanes that incorporate or
have incorporated Marburger winglets. These winglets are installed
following STC No. SA00490LA. Use the winglet usage factor in Table 2
of paragraph (c)(4) of this AD, the wing lower spar cap safe life
specified in Table 1 of paragraph (c)(1) of this AD, and the
instructions included in Appendix 1 to this AD to determine the new
safe life of airplanes that incorporate or have incorporated
Marburger winglets:

 Table 2--Winglet Usage Factor To Determine the Safe Life for Airplanes
  That Incorporate or Have Incorporated Marburger Winglets per STC No.
                                SA00490LA
------------------------------------------------------------------------
                                                               Winglet
              Model                       Serial Nos.           usage
                                                                factor
------------------------------------------------------------------------
AT-401...........................  0662 through 0951.......          1.6
AT-401B..........................  0952 through 1020,                1.1
                                    except 1015.
AT-401B..........................  1015 and all beginning            1.1
                                    with 1021.
AT-402...........................  0694 through 0951.......          1.6
AT-402A..........................  0738 through 0951.......          1.6
AT-402A..........................  0952 through 1020.......          1.1
AT-402A..........................  All beginning with 1021.          1.1
AT-402B..........................  0966 through 1020,                1.1
                                    except 1015.
AT-402B..........................  1015 and all beginning            1.1
                                    with 1021.
------------------------------------------------------------------------

Unsafe Condition

    (d) This AD is the result of fatigue cracking of the wing main
spar lower cap at the center splice joint outboard fastener hole.
The actions specified in this AD are intended to detect and correct
cracks in the wing main spar lower cap, which could result in
failure of the spar cap and lead to wing separation and loss of
control of the airplane.

Compliance

    (e) Safe Life Record: For all affected airplanes, modify the
applicable aircraft records (logbook) as follows to show the safe
life for the wing lower spar cap listed in this AD (use the
information from paragraph (c) of this AD and Appendix 1 to this AD,
as applicable).
    (1) Incorporate the following into the aircraft logbook:
``Following this AD, the wing lower spar cap is life limited to ----
hours time-in-service (TIS).'' Insert the applicable safe life
number from the applicable tables in paragraph (c) of this AD and
Appendix 1 to this AD.
    (i) Do the logbook entry within the next 10 hours TIS after
April 21, 2006 (the effective date of AD 2006-08-08).
    (ii) A person holding at least a private pilot certificate as
authorized by section 43.7 of the Federal Aviation Regulations (14
CFR 43.7) may modify the aircraft records. Make an entry into the
aircraft logbook showing compliance with this portion of the AD in
accordance with section 43.9 of the Federal Aviation Regulations (14
CFR 43.9)..
    (2) Wing Spar Replacement: For all affected airplanes, replace
the wing lower spar cap following Snow Engineering Drawing Number
21088, dated November 3, 2004. Replace upon accumulating the safe
life used in paragraph (e)(1) of this AD or within the next 50 hours
TIS after April 21, 2006 (the effective date of AD 2006-08-08),
whichever occurs later. The owner/operator may not do the spar cap
replacement, unless he/she is a properly certified mechanic.
    (f) Inspection Requirements: For all affected airplanes, except
Model AT-402A, all serial numbers beginning with 0952, and Model AT-
402B, all serial numbers beginning with 0966, do the initial
inspection of the outboard two lower spar cap bolt holes using the
wing spar lower cap TIS schedules listed in Table 3. Follow Snow
Engineering Co. Process Specification 197, page 1, revised
June 4, 2002, pages 2 through 4, dated February 23, 2001, and page
5, dated May 3, 2002. After the initial inspection, perform
repetitive inspections at the repetitive inspection intervals listed
in Table 3. Use the same procedure for the repetitive inspections as
for the initial inspection. If not already done, install access
panels at the time of the first inspection following Snow
Engineering Service Letter 202, page 3, dated October 16,
2000.

    Note: Hours listed in the table are in hours TIS and the phrase
``within the next ---- hours'' refers to ``within the next ----
hours after April 21, 2006 (the effective date of AD 2006-08-08).''

                                            Table 3--Inspection Times
----------------------------------------------------------------------------------------------------------------
                                                                                Repetitive
                                                           Current wing spar                          inspection
              Model                    Serial Nos.        lower cap TIS hours   Initial inspection     interval
                                                                                (hours)
----------------------------------------------------------------------------------------------------------------
AT-400..........................  All beginning with     Greater than 7,750..  Within the next 50            900
                                   0416.                                        hours TIS or upon
                                                                                the accumulation of
                                                                                8,000 hours TIS,
                                                                                whichever is later.
AT-401..........................  0662-0951............  Greater than 6,250..  Within the next 50            700
                                                                                hours TIS or upon
                                                                                the accumulation of
                                                                                6,500 hours TIS,
                                                                                whichever is later.
AT-401..........................  0662-0951............  Greater than 4,350    Within the next 250           700
                                                          but less than or      hours TIS or upon
                                                          equal to 6,250.       the accumulation of
                                                                                4,850 hours TIS,
                                                                                whichever is later.
AT-401..........................  0662-0951............  Greater than 2,750    Within the next 500           700
                                                          but less than or      hours TIS.
                                                          equal to 4,350.
AT-401..........................  0662-0951............  Less than or equal    Upon the                      700
                                                          to 2,750.             accumulation of
                                                                                3,250 hours TIS.
AT-401B.........................  0952-1020 except 1015  Greater than 3,950..  Within the next 50            600
                                                                                hours TIS or upon
                                                                                the accumulation of
                                                                                4,200 hours TIS,
                                                                                whichever is later.
AT-401B.........................  0952-1020 except 1015  Greater than 2,650    Within the next 250           600
                                                          but less than or      hours TIS or upon
                                                          equal to 3,950.       the accumulation of
                                                                                3,150 hours TIS,
                                                                                whichever is later.
AT-401B.........................  0952-1020 except 1015  Greater than 1,600    Within the next 500           600
                                                          but less than or      hours TIS.
                                                          equal to 2,650.
AT-401B.........................  0952-1020 except 1015  Less than or equal    Upon the                      600
                                                          to 1,600.             accumulation of
                                                                                2,100 hours TIS.

AT-401B.........................  1015 and 1021-1124...  Greater than 4,450..  Within the next 50            600
                                                                                hours TIS or upon
                                                                                the accumulation of
                                                                                4,700 hours TIS,
                                                                                whichever is later.
AT-401B.........................  1015 and 1021-1124...  Greater than 3,000    Within the next 250           600
                                                          but less than or      hours TIS or upon
                                                          equal to 4,450.       the accumulation of
                                                                                3,500 hours TIS,
                                                                                whichever is later.
AT-401B.........................  1015 and 1021-1124...  Greater than 1,850    Within the next 500           600
                                                          but less than or      hours TIS.
                                                          equal to 3,000.
AT-401B.........................  1015 and 1021-1124...  Less than or equal    Upon the                      600
                                                          to 1,850.             accumulation of
                                                                                2,350 hours TIS.
AT-401B.........................  All beginning with     Greater than 4,450..  Within the next 50          1,000
                                   1125.                                        hours TIS or upon
                                                                                the accumulation of
                                                                                4,700 hours TIS,
                                                                                whichever is later.
AT-401B.........................  All beginning with     Greater than 3,000    Within the next 250         1,000
                                   1125.                  but less than or      hours TIS or upon
                                                          equal to 4,450.       the accumulation of
                                                                                3,500 hours TIS,
                                                                                whichever is later.
AT-401B.........................  All beginning with     Greater than 1,850    Within the next 500         1,000
                                   1125.                  but less than or      hours TIS.
                                                          equal to 3,000.
AT-401B.........................  All beginning with     Less than or equal    Upon the                    1,000
                                   1125.                  to 1,850.             accumulation of
                                                                                2,350 hours TIS.
AT-402/AT-402A..................  0694-0951............  Greater than 4,250..  Within the next 50            700
                                                                                hours TIS or upon
                                                                                the accumulation of
                                                                                4,500, whichever is
                                                                                later.
AT-402/AT-402A..................  0694-0951............  Greater than 2,850    Within the next 250           700
                                                          but less than or      hours TIS or upon
                                                          equal to 4,250.       the accumulation of
                                                                                3,350 hours TIS,
                                                                                whichever is later.
AT-402/AT-402A..................  0694-0951............  Greater than 1,750    Within the next 500           700
                                                          but less than or      hours TIS.
                                                          equal to 2,850.
AT-402/AT-402A..................  0694-0951............  Less than or equal    Upon the                      700
                                                          to 1,750.             accumulation of
                                                                                2,250 hours TIS.
----------------------------------------------------------------------------------------------------------------

    (g) For all affected airplanes: Before further flight after the
inspection in which cracks are found, replace any cracked wing lower
spar cap following Snow Engineering Drawing Number 21088, dated
November 3, 2004.
    (h) For all affected airplanes, except Model AT-402A, all serial
numbers beginning with 0952, and except Model AT-402B, all serial
numbers beginning with 0966: Report to the FAA any cracks detected
as the result of each inspection required by paragraph (f) of this
AD on the form in Figure 1 of this AD.
    (1) Only if cracks are found, send the report within 10 days
after the inspection required in paragraph (f) of this AD.
    (2) The Office of Management and Budget (OMB) approved the
information collection requirements contained in this regulation
under the provisions of the Paperwork Reduction Act and assigned OMB
Control Number 2120-0056.
    (i) For all affected airplanes: Upon the accumulation of the
life used in paragraph (e)(1) of this AD or within the next 50 hours
TIS after April 21, 2006 (the effective date of AD 2006-08-08),
whichever occurs later, you must replace your wing lower spar cap
before further flight following Snow Engineering Drawing Number
21088, dated November 3, 2004.
    (j) For Model AT-402A airplanes, all serial numbers beginning
with 0952; and Model AT-402B airplanes, all serial numbers beginning
with 0966: In lieu of the safe life used in paragraph (e)(1) of this
AD, you may eddy-current inspect and modify the wing lower spar cap.
The inspection schedule and modification procedures are included in
Appendix 2 to this AD.
    (k) For all affected airplanes (those complying with the actions
in the AD or alternative method of compliance (AMOC)): One of the
following must do the inspection:
    (1) A level 2 or 3 inspector certified in eddy current
inspection using the guidelines established by the American Society
for Nondestructive Testing or MIL-STD-410; or
    (2) A person authorized to perform AD work and who has completed
and passed the Air Tractor, Inc. training course on Eddy Current
Inspection on wing lower spar caps.
BILLING CODE 4910-13-P

[GRAPHIC] [TIFF OMITTED] TP10DE08.002

BILLING CODE 4910-13-C
    Mail report to: Manager, Fort Worth ACO, ASW-150, 2601 Meacham
Blvd., Fort Worth, TX 76193-0150; or fax to<PHONE_NUMBER>.

Special Flight Permit

    (l) Under 14 CFR part 39.23, we are allowing special flight
permits for the purpose of compliance with this AD under the
following conditions:
    (1) Only operate in day visual flight rules (VFR).
    (2) Ensure that the hopper is empty.
    (3) Limit airspeed to 135 miles per hour (mph) indicated
airspeed (IAS).
    (4) Avoid any unnecessary g-forces.
    (5) Avoid areas of turbulence.
    (6) Plan the flight to follow the most direct route.

Alternative Methods of Compliance (AMOCs)

    (m) The Manager, Fort Worth or Los Angeles Airplane
Certification Office (ACO), FAA, has the authority to approve AMOCs
for this AD, if requested using the procedures found in 14 CFR
39.19. Before using any approved AMOC on any airplane to which the
AMOC applies, notify your appropriate principal inspector (PI) in
the FAA Flight Standards District Office (FSDO), or lacking a PI,
your local FSDO. For AMOC approval, send information to ATTN:
    (1) For the airplanes that do not incorporate and never have
incorporated Marburger winglets: Rob Romero, Aerospace Engineer,
FAA, Fort Worth Airplane Certification Office, 2601 Meacham
Boulevard, Fort Worth, Texas 76193-0150; telephone:<PHONE_NUMBER>;
facsimile:<PHONE_NUMBER>.

    (2) For airplanes that incorporate or have incorporated
Marburger winglets: John Cecil, Aerospace Engineer, Los Angeles
Aircraft Certification Office, FAA, 3960 Paramount Boulevard,
Lakewood, California 90712; telephone:<PHONE_NUMBER>; facsimile:
(562) 627-5210.
    (n) AMOCs approved for AD 2001-10-04, AD 2001-10-04 R1, or AD
2002-11-05 for the AT-400 series airplanes are not considered
approved for this AD.
    (o) AMOCs approved for the repetitive inspection requirements of
AD 2006-08-08 are approved for this AD until the scheduled
modification date required by this AD.

Related Information

    (p) To get copies of the service information referenced in this
AD, contact Air Tractor, Incorporated, P.O. Box 485, Olney, Texas
76374; telephone:<PHONE_NUMBER>; facsimile:<PHONE_NUMBER>;
Internet: http://www.airtractor.com; or Marburger Enterprises, Inc.,
1227 Hillcourt, Williston, North Dakota 58801; telephone: (800) 893-
1420 or<PHONE_NUMBER>; facsimile:<PHONE_NUMBER>. To view the AD
docket, go to U.S. Department of Transportation, Docket Operations,
M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey
Avenue, SE., Washington, DC 20590, or on the Internet at http://
www.regulations.gov.

Appendix 1 to Docket No. FAA-2006-23646

    The following provides procedures for determining the safe life
for those Models AT-401, AT-401B, AT-402, AT-402A, and AT-402B
airplanes that incorporate or have incorporated Marburger winglets.
These winglets are installed following Supplemental Type Certificate
(STC) No. SA00490LA.
    What if I removed the Marburger winglets prior to further flight
after April 21, 2006 (the effective date of AD 2006-08-08) or prior
to April 21, 2006 (the effective date of AD 2006-08-08)?
    1. Review your airplane's logbook to determine your airplane's
time in service (TIS) with winglets installed per Marburger STC No.
SA00490LA. This includes all time spent with the winglets currently
installed and any previous installations where the winglet was
installed and later removed.

    Example: A review of your airplane's logbook shows that you have
accumulated 350 hours TIS since incorporating Marburger STC No.
SA00490LA. Further review of the airplane's logbook shows that a
previous owner had installed the STC and later removed the winglets
after accumulating 150 hours TIS. Therefore, your airplane's TIS
with the winglets installed is 500 hours.
    If you determine that the winglet STC has never been
incorporated on your airplane, then your safe life is presented in
paragraph (c)(1) of this AD. Any future winglet installation will be
subject to a reduced safe life per these instructions.
    2. Determine your airplane's unmodified safe life from paragraph
(c)(1) of this AD.

    Example: Your airplane is a Model AT-401B, serial number 1022.
From paragraph (c)(1) of this AD, the unmodified safe life of your
airplane is 7,777 hours TIS.
    All examples from hereon will be based on the Model AT-401B,
serial number 1022 airplane.
    3. Determine the winglet usage factor from paragraph (c)(4) of
this AD.

    Example: Again, your airplane is a Model AT-401B, serial number
1022. From paragraph (c)(4) of this AD, your winglet usage factor is
1.1.
    4. Adjust the winglet TIS to account for the winglet usage
factor. Multiply the winglet TIS (result of Step 1 above) by the
winglet usage factor (result of Step 3 above).

    Example: Winglet TIS is 500 hours x a winglet usage factor of
1.1. The adjusted winglet TIS is 550 hours.
    5. Calculate the winglet usage penalty. Subtract the winglet TIS
(result of Step 1 above) from the adjusted winglet TIS (result of
Step 4 above).

    Example: Adjusted winglet TIS-the winglet TIS = winglet usage
penalty.
    (550 hours)-(500 hours TIS) = (50 hours TIS).
    6. Adjust the safe life of your airplane to account for winglet
usage. Subtract the winglet usage penalty (result of Step 5 above)
result from the unmodified safe life from paragraph (c)(1) of this
AD (result of Step 2 above.).

    Example: Unmodified safe life-winglet usage penalty = adjusted
safe life.
    (7,777 hours TIS)-(50 hours TIS) = (7,727 hours TIS).
    7. If you remove the winglets from your airplane before further
flight or no longer have the winglets installed on your airplane,
the safe life of your airplane is the adjusted safe life (result of
Step 6 above). Enter this number in paragraph (e)(1) of this AD and
the airplane logbook.
    What if I have the Marburger winglet installed as of April 21,
2006 (the effective date of AD 2006-08-08) and plan to operate my
airplane without removing the winglet?
    1. Review your airplane's logbook to determine your airplane's
TIS without the winglets installed.

    Example: A review of your airplane's logbook shows that you have
accumulated 1,500 hours TIS, including 500 hours with the Marburger
winglets installed. Therefore, your airplane's TIS without the
winglets installed is 1,000 hours.
    2. Determine your airplane's unmodified safe life from paragraph
(c)(1) of this AD.

    Example: Your airplane is a Model AT-401B, serial number 1022.
From paragraph (c)(1) of this AD, the unmodified safe life of your
airplane is 7,777 hours TIS.
    All examples from hereon will be based on the Model AT-401B,
serial number 1022 airplane.
    3. Determine the winglet usage factor from paragraph (c)(4) of
this AD.

    Example: Again, your airplane is a Model AT-401B, serial number
1022. From paragraph (c)(4) of this AD, your winglet usage factor is
1.1.
    4. Determine the potential winglet TIS. Subtract the TIS without
the winglets installed (result of Step 1 above) from the unmodified
safe life (result of Step 2 above).

    Example: Unmodified safe life-TIS without winglets = Potential
winglet TIS.
    (7,777 hours TIS)-(1,000 hours TIS) = (6,777 hours TIS).
    5. Adjust the potential winglet TIS to account for the winglet
usage factor. Divide the potential winglet TIS (result of Step 4
above) by the winglet usage factor (result of Step 3 above).

    Example: Potential winglet TIS / Winglet usage factor = Adjusted
potential winglet TIS.
    (6,777 hours TIS) / (1.1) = (6,155 hours TIS).
    6. Calculate the winglet usage penalty. Subtract the adjusted
potential winglet TIS (result of Step 5 above) from the potential
winglet TIS (result of Step 4 above).

    Example: Potential winglet TIS-Adjusted potential winglet TIS =
Winglet usage penalty.
    (6,777 hours TIS)-(6,155 hours TIS) = (622 hours TIS).
    7. Adjust the safe life of your airplane to account for the
winglet installation. Subtract the winglet usage penalty (result of
Step 6 above) from the unmodified safe life from paragraph (c)(1) of
this AD (the result of Step 2 above).

    Example: Unmodified safe life-Winglet usage penalty = Adjusted
safe life.
    (7,777 hours TIS)-(622 hours TIS) = (7,155 hours TIS).
    8. Enter the adjusted safe life (result of Step 7 above) in
paragraph (e)(1) of this AD and the airplane logbook.
    What if I install or remove the Marburger winglet from my
airplane in the future?
    If, at any time in the future, you install or remove the
Marburger winglet STC from your airplane, you must repeat the
procedures in this Appendix to determine the airplane's safe life.

Appendix 2

Alternative Method of Compliance (AMOC) to Docket No. FAA-2006-23646

Optional Inspection Program

    For Model AT-402A airplanes, all serial numbers (S/Ns) beginning
with 0952, and Model AT-402B airplanes, all S/Ns beginning with
0966, that do not incorporate and never have incorporated Marburger
winglets installed following STC No. SA00490LA; you may begin a
repetitive inspection interval program as an alternative to the safe
life requirement of this AD with the following provisions:
    1. Upon accumulating 1,600 hours time-in-service (TIS) or within
the next 50 hours TIS after April 21, 2006 (the effective date of AD
2006-08-08), whichever occurs later, eddy-current inspect the
outboard two lower spar cap bolt holes following Snow Engineering
Process Specification 197, page 1, revised June 4, 2002;
pages 2 through 4, dated February 23, 2001; and page 5, dated May 3,
2002. The inspection must be done by one of the following:
    a. A Level 2 or Level 3 inspector that is certified for eddy-
current inspection using the guidelines established by the American
Society for Nondestructive Testing or MIL-STD-410; or
    b. A person authorized to do AD work and who has completed and
passed the Air

Tractor, Inc. training course on Eddy Current Inspection on wing
lower spar caps.
    2. Repeat these inspections at intervals of (as applicable):
    a. 600 hours TIS:
    i. Model AT-402A, S/Ns 1021 through 1124.
    ii. Model AT-402B, S/Ns 1015, and 1021 through 1124.
    b. 600 hours TIS:
    i. Model AT-402A, S/Ns 0952 through 1020.
    ii. Model AT-402B, S/Ns 0966 through 1020, except 1015.
    c. 1,000 hours TIS:
    i. Model AT-402A, all S/Ns beginning with 1112.
    ii. Model AT-402B, all S/Ns beginning with 1125.
    d. If the outboard two lower spar cap bolt holes have been cold
worked following Snow Engineering Service Letter  238 or
239, both dated September 30, 2004, then you may double the
inspection intervals listed in a., b., and c. above (800 hours TIS,
1,200 hours TIS, or 2,000 hours TIS, as applicable) (See Step 8.--
re: mid cycle cold work).
    e. Your logbook entry must include the work done and the
inspection intervals that are upcoming, as follows:
    ``Following AD 2006-08-08, at XXXX {insert hours TIS of the
initial pre-modification inspection{time}  hours TIS an eddy-current
inspection has been performed. As of now, the safe life listed in
the AD no longer applies to this airplane. This airplane must be
eddy-current inspected at intervals not to exceed {400/600/800/
1,000/1,200/2,000, as applicable{time}  hours TIS. The first of
these inspections is due at {insert the total number of hours TIS
the first of these inspections is due{time}  hours TIS.''
    3. If at any time a crack is found, and:
    a. If the crack indication goes away by doing the initial steps
of the modification following the applicable sheet of Snow
Engineering Co. Drawing Number 20992, then you may continue to
modify your wing. After modification, proceed to Step 5.
    b. If the crack indication does not go away by doing the initial
steps of the modification following the applicable sheet of Snow
Engineering Co. Drawing Number 20992, then you must replace all
parts and hardware listed in Step 7.
    c. Report to the FAA any cracks found using the form in Figure 1
of this AD.
    4. Upon accumulating 4,000 hours TIS, you must:
    a. Modify your center splice connection following the applicable
sheet of Snow Engineering Co. Drawing Number 20992, unless already
done. Before doing the modification, do an eddy-current inspection
following Snow Engineering Process Specification 197, page
1, revised June 4, 2002; pages 2 through 4, dated February 23, 2001;
and page 5, dated May 3, 2002. (See Step 9.). If, as of April 21,
2006 (the effective date of AD 2006-08-08), your airplane is over or
within 50 hours of reaching the 4,000-hour TIS modification
requirement, then you must perform the modification within 50 hours
TIS.
    b. Your logbook entry must include the work done and the
inspection intervals that are upcoming, as follows:
    ``Following AD 2006-08-08, at XXXX {insert hours TIS of the
modification{time}  hours TIS an eddy-current inspection has been
performed. As of now, the safe life listed in the AD no longer
applies to this airplane. This airplane must be eddy-current
inspected at {insert the number of hours TIS at modification plus
1,600 hours TIS{time}  hours TIS.
    5. Upon accumulating 1,600 hours TIS after modification, inspect
the left-hand and right-hand outboard two lower spar cap bolt holes
following Snow Engineering Process Specification 197, page
1, revised June 4, 2002; pages 2 through 4, dated February 23, 2001;
and page 5, dated May 3, 2002.
    6. Repetitively thereafter inspect at intervals not to exceed:
    a. 1,000 hours TIS; or
    b. 2,000 hours TIS if the outboard two lower spar cap bolt holes
have been cold worked following Snow Engineering Service Letter
239, dated September 30, 2004 (See Step 8.).
    c. Your logbook entry must include the work done and the post-
modification inspection intervals that are upcoming, as follows:
    ``Following AD 2006-08-08, at XXXX {insert hours TIS of the
initial post-modification inspection{time}  hours TIS an eddy-
current inspection has been performed. As of now, the safe life
listed in the AD no longer applies to this airplane. This airplane
must be eddy-current inspected at intervals not to exceed {1,000/
2,000, as applicable{time}  hours TIS. The first of these
inspections is due at {insert the total number of hours TIS the
first of these inspections is due{time}  hours TIS.''
    d. If at any time a crack is found, then before further flight
you must replace the lower spar caps, splice blocks, and wing attach
angles and hardware. You must also notify the FAA using the form in
Figure 1 of this AD.
    7. Upon accumulating 8,000 hours TIS, before further flight you
must replace the lower spar caps, splice blocks, and wing attach
angles (P/N 20693-1) and associated hardware. No additional time
will be authorized for airplanes that are at or over 8,000 hours TIS
(See Step 9.).
    8. If you decide to cold work your bolt holes following Snow
Engineering Service Letter 238 or 239, both dated
September 30, 2004, at a TIS that does not coincide with a scheduled
inspection following this AD, then eddy-current inspect at the time
of cold working and then begin the 800/1,200/2000 hour TIS
inspection intervals (2 times the intervals listed in Steps 2.a.,
2.b., 2.c., and 6.a. listed above).
    9. If you have modified your airplane before accumulating 4,000
hours TIS, then you may continue to fly your airplane past
(modification + 4,000 hours TIS) provided you cut your inspection
intervals in half. Make a logbook entry following Step 6.c. to
reflect these reduced inspection intervals. Upon accumulating 8,000
hours TIS, you must comply with Step 7 above. See example:

    Example: An AT-402B had the two-part modification installed at
3,000 hours TIS and the bolt holes have not been cold worked.
    The first inspection would occur at 4,600 hours TIS. From Step
5, this is modification plus 1,600 hours.
    Inspections would follow at 5,600 and 6,600 hours TIS. From Step
6a, this is 1,000-hour TIS inspection intervals.
    There is another inspection at 7,000 hours TIS (modification
plus 4,000 hours TIS). This relates to the 8,000-hour TIS inspection
from Step 7, which is modification plus 4,000 hours TIS, except in
this example the modification took place at 3,000 hours TIS instead
of 4,000 hours TIS listed in Step 4.
    This airplane may continue to fly if inspected again at 7,500
hours TIS, which is 500 hours TIS. This 500-hour time corresponds to
Step 9 where you cut your inspection interval from Step 6a in half.
    Upon accumulating 8,000 hours TIS (this is the same as Step 7),
you must replace the parts listed in Step 7 above.
    For Model AT-402A airplanes, all S/Ns beginning with 0952, and
Model AT-402B airplanes, all S/Ns beginning with 0966, that
incorporate or have incorporated Marburger winglets installed
following STC No. SA00490LA; you may begin a repetitive inspection
interval program as an alternative to the safe life requirement of
this AD following the steps above with the following provisions:
    If you have removed the winglets, then calculate new, reduced
hours for Steps 1, 4, 5, and 7 above, as applicable, based on the
winglet usage factor listed in paragraph (c)(4) and Appendix 2 of
this AD.
    You may repetitively inspect at the same intervals listed in
Step 2 above provided that you do not re-install the winglets.

    Example: An AT-402B airplane, S/N 1020, had winglets installed
at 200 hours TIS and removed at 800 hours TIS.
    The winglet usage factor is: 1.1.
    Calculate equivalent hours: 600 hours TIS with winglets x 1.1 =
660 hours TIS.
    Winglet usage penalty = 660 - 600 = 60.
    New Step 1 Pre-Modification Initial Inspection time = 1,600 - 60
= 1,540 hours TIS.
    Retained Step 2 Pre-Modification Inspection interval: Since the
winglets are removed, the Pre-Modification Inspection interval
remains at 600 hours TIS.
    New Step 4 Modification time = 4,000 - 60 = 3,940 hours TIS.
    New Step 5 Post-Modification Initial Inspection time = 3,940 +
1,600 = 5,540 hours TIS.
    Retained Step 6 Post-Modification Inspection interval: Since the
winglets are removed the Post-Modification Inspection interval
remains at 1,000/2,000 hours TIS.
    New Step 7 Replacement time = 8,000 - 60 = 7,940 hours TIS.
    Use the Retained Step 2 interval, the New Step 5 time, and the
Retained Step 6 interval to make appropriate logbook entries for the
pre- and post-modification intervals, using the format presented in
Steps 2.e., 4.b., and 6.c.
    If you have not removed the winglets, then calculate new,
reduced hours for Steps 1, 2, 4, 5, 6, and 7 above, as applicable,
based on the winglet usage factor listed in paragraph (c)(4) and
Appendix 2 of this AD.
    Repetitively thereafter inspect at intervals not to exceed the
appropriate interval listed

in the step above divided by the winglet usage factor.

    Example: An AT-402B, S/N 1,000 has had winglets on since new.
    The winglet usage factor is: 1.1.
    New Step 1 Pre-Modification Initial Inspection time: 1,600 / 1.1
= 1,455 hours TIS.
    New Step 2 Pre-Modification Inspection interval: 600 / 1.1 = 545
hours TIS.
    New Step 4 Modification time: 4,000 / 1.1 = 3,636 hours TIS.
    New Step 5 Post-Modification Initial Inspection time: 3,636 +
(1,600 / 1.1) = 5,090 hours TIS.
    New Step 6 Post-Modification Inspection interval: 1,000 / 1.1 =
909 hours TIS.
    New Step 7 Replacement time: 8,000 / 1.1 = 7,273 hours TIS.
    Use the reduced hours you calculate in New Step 2, New Step 5,
and New Step 6 to make appropriate logbook entries for the pre- and
post-modification inspection intervals, using the format presented
in Steps 2.e., 4.b., and 6.c.

    Issued in Kansas City, Missouri, on December 4, 2008.
Kim Smith,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. E8-29165 Filed 12-9-08; 8:45 am]

BILLING CODE 4910-13-P