[Federal Register Volume 72, Number 50 (Thursday, March 15, 2007)]
[Proposed Rules]
[Pages 12131-12133]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-4737]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-27212; Directorate Identifier 2007-CE-011-AD]
RIN 2120-AA64


Airworthiness Directives; Air Tractor, Inc. Models AT-602, AT-
802, and AT-802A Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede Airworthiness Directive (AD) 2006-22-
08, which applies to all Air Tractor, Inc. (Air Tractor) Models AT-602, 
AT-802, and AT-802A airplanes. AD 2006-22-08 currently requires you to 
repetitively inspect the engine mount for any cracks, repair or replace 
any cracked engine mount, and report any cracks found to the FAA. Since 
we issued AD 2006-22-08, the FAA has received reports of two Model AT-
802A airplanes with cracked engine mounts (at 2,815 hours time-in-
service (TIS) and 1,900 hours TIS) below the initial compliance time in 
AD 2006-22-08. The FAA has determined that an initial inspection at 
1,300 hours TIS is required instead of 4,000 hours TIS required by AD 
2006-22-08. Consequently, this proposed AD would retain the actions of 
AD 2006-22-08 while requiring the initial inspection at 1,300 hours 
TIS. We are proposing this AD to detect and correct cracks in the 
engine mount, which could result in failure of the engine mount. Such 
failure could lead to separation of the engine from the airplane.

DATES: We must receive comments on this proposed AD by May 14, 2007.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD:
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-0001.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
    For service information identified in this proposed AD, contact Air 
Tractor, Inc., P.O. Box 485, Olney, Texas 76374; telephone: (940) 564-
5616; facsimile: (940) 564-5612.

FOR FURTHER INFORMATION CONTACT: Andrew McAnaul, Aerospace Engineer, 
ASW-150 (c/o MIDO-43), 10100 Reunion Place, Suite 650, San Antonio, 
Texas 78216; telephone: (210) 308-3365; facsimile: (210) 308-3370.

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-
2007-27212; Directorate Identifier 2007-CE-011-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://dms.dot.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

    Two reports from Air Tractor of cracked engine mounts resulting 
from fatigue caused us to issue AD 2006-22-08, Amendment 39-14805 (71 
FR 62910, October 27, 2006). AD 2006-22-08 currently requires the 
following on all Air Tractor Models AT-602, AT-802, and AT-802A 
airplanes:
     Inspect (initially and repetitively) the engine mount for 
any cracks;
     Repair or replace any cracked engine mount; and
     Report any cracks found to the FAA.
    Since we issued AD 2006-22-08, the FAA has received reports of two 
Model AT-802A airplanes with cracked engine mounts (at 2,815 hours TIS 
and 1,900 hours TIS) below the initial compliance time in AD 2006-22-
08. The FAA has determined that an initial inspection at 1,300 hours 
TIS is required instead of 4,000 hours TIS as required by AD 2006-22-
08.
    This condition, if not corrected, could result in failure of the 
engine mount. Such failure could lead to separation of the engine from 
the airplane.

Relevant Service Information

    We have reviewed Snow Engineering Co. Service Letter 253, 
dated December 12, 2005, revised January 22, 2007.
    The service information describes procedures for performing a 
visual inspection for cracks of the engine mount and requesting a 
repair scheme from the manufacturer.
    Snow Engineering Co. has a licensing agreement with Air Tractor 
that allows them to produce technical data to use for Air Tractor 
products.

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 supersede AD 2006-22-08 with a new AD that would require you to 
repetitively inspect the engine mount for any cracks, repair or replace 
any cracked engine mount, and report any cracks found to the FAA. To 
repair a cracked engine mount, you would obtain an FAA-approved repair 
scheme from Air Tractor following the instructions in the service 
information.
    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 368 airplanes in the U.S. 
registry.
    We estimate the following costs to do each required inspection:

[[Page 12132]]



----------------------------------------------------------------------------------------------------------------
                                                                                                   Total cost on
                                                                                  Total cost per  U.S. operators
                  Labor cost                               Parts cost              airplane per     for initial
                                                                                    inspection      inspection
----------------------------------------------------------------------------------------------------------------
1.5 work-hours x $80 per hour = $120.........  Not Applicable...................            $120         $44,160
----------------------------------------------------------------------------------------------------------------

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

------------------------------------------------------------------------
                                                          Total cost per
               Labor cost                   Parts cost     airplane per
                                                            replacement
------------------------------------------------------------------------
81 work-hours x $80 per hour = $6,480...          $3,982         $10,462
------------------------------------------------------------------------

    Any required ``upon-condition'' repairs would vary depending upon 
the damage found during each inspection. Based on this, we have no way 
of determining the potential repair costs for each airplane.

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://dms.dot.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 (800) 647-5227) 
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, 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) 2006-22-08, Amendment 39-14805 (71 FR 62910, October 27, 2006), 
and adding the following new AD:

Air Tractor, Inc: Docket No. FAA-2007-27212; Directorate Identifier 
2007-CE-011-AD.

Comments Due Date

    (a) We must receive comments on this airworthiness directive 
(AD) action by May 14, 2007.

Affected ADs

    (b) This AD supersedes AD 2006-22-08, Amendment 39-14805.

Applicability

    (c) This AD affects all Models AT-602, AT-802, and AT-802A 
airplanes, all serial numbers, that are certificated in any 
category.

Unsafe Condition

    (d) This AD results from reports of two Model AT-802A airplanes 
with cracked engine mounts (at 2,815 hours time-in-service (TIS) and 
1,900 hours TIS) below the initial compliance time in AD 2006-22-08. 
The FAA has determined that an initial inspection at 1,300 hours TIS 
is required instead of 4,000 hours TIS as required by AD 2006-22-08. 
We are issuing this AD to detect and correct cracks in the engine 
mount, which could result in failure of the engine mount. Such 
failure could lead to separation of the engine from the airplane.

Compliance

    (e) To address this problem, you must do the following, unless 
already done:

[[Page 12133]]



------------------------------------------------------------------------
           Actions                 Compliance            Procedures
------------------------------------------------------------------------
(1) Visually inspect the      Initially inspect     Follow Snow
 engine mount for any cracks.  upon accumulating     Engineering Co.
                               1,300 hours TIS or    Service Letter
                               within the next 100   253, dated
                               hours TIS after the   December 12, 2005,
                               effective date of     revised January 22,
                               this AD, whichever    2007.
                               occurs later,
                               unless already
                               done. Thereafter,
                               inspect
                               repetitively at
                               intervals not to
                               exceed 300 hours
                               TIS.
(2) If you find any crack     Before further        For obtaining a
 damage, do the following:     flight after any      repair scheme or
(i) Obtain an FAA-approved     inspection required   replacement
 repair scheme or              by paragraph (e)(1)   procedure: Contact
 replacement procedure from    of this AD where      Air Tractor Inc.,
 the manufacturer; and.        crack damage is       P.O. Box 485,
(ii) Repair following the      found. If you         Olney, Texas 76374;
 FAA-approved repair scheme    repair the cracked    telephone: (940)
 or replace the engine mount   engine mount, then    564-5616;
 with a new engine mount       continue to           facsimile: (940)
 following the replacement     reinspect at          564-5612.
 procedure..                   intervals not to
                               exceed 300 hours
                               TIS, unless the
                               repair scheme
                               states differently.
                               If you replace the
                               engine mount, then
                               initially inspect
                               upon accumulating
                               1,300 hours TIS and
                               repetitively at
                               intervals not to
                               exceed 300 hours
                               TIS.
(3) Report any cracks that    Within the next 30    The Office of
 you find to the FAA at the    days after you find   Management and
 address specified in          the cracks or         Budget (OMB)
 paragraph (f) of this AD.     within the next 30    approved the
 Include in your report:       days after the        information
(i) Airplane serial number;.   effective date of     collection
(ii) Airplane hours TIS and    this AD, whichever    requirements
 engine mount hours TIS;.      occurs later.         contained in this
(iii) Crack location(s) and                          regulation under
 size(s);.                                           the provisions of
(iv) Corrective action                               the Paperwork
 taken; and.                                         Reduction Act of
(v) Point of contact name                            1980 (44 U.S.C.
 and telephone number..                              3501 et seq.) and
                                                     assigned OMB
                                                     Control Number 2120-
                                                     0056.
------------------------------------------------------------------------

Alternative Methods of Compliance (AMOCs)

    (f) The Manager, Fort Worth Airplane Certification Office, FAA, 
ATTN: Andrew McAnaul, Aerospace Engineer, ASW-150 (c/o MIDO-43), 
10100 Reunion Place, Suite 650, San Antonio, Texas 78216; telephone: 
(210) 308-3365; facsimile: (210) 308-3370, 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.
    (g) AMOCs approved for AD 2006-22-08 are not approved for this 
AD.

Related Information

    (h) To get copies of the service information referenced in this 
AD, contact Air Tractor Inc., P.O. Box 485, Olney, Texas 76374; 
telephone: (940) 564-5616; facsimile: (940) 564-5612. To view the AD 
docket, go to the Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-
401, Washington, DC, or on the Internet at http://ms.dot.gov. The 
docket number is Docket No. FAA-2007-27212; Directorate Identifier 
2007-CE-011-AD.

    Issued in Kansas City, Missouri, on March 8, 2007.
David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-4737 Filed 3-14-07; 8:45 am]
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