[Federal Register Volume 71, Number 84 (Tuesday, May 2, 2006)]
[Proposed Rules]
[Pages 25793-25795]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-6584]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24228; Directorate Identifier 2006-CE-22-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 adopt a new airworthiness directive (AD) for all 
Air Tractor, Inc. Models AT-602, AT-802, and AT-802A airplanes. This 
proposed AD 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. This proposed AD results from reports of 
cracked engine mounts. 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 June 27, 2006.

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.
     Government-wide rulemaking Web site: Go to http://www.regulations.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.
    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-
2006-24228; Directorate Identifier 2006-CE-22-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

    We received two reports from Air Tractor, Inc. of cracked engine 
mounts resulting from fatigue. One report was for a Model AT-602 
airplane. The specific airplane model with the other crack is 
unverified. This AD applies to Air Tractor, Inc. Models AT-602, AT-802, 
and AT-802A airplanes due to design similarity.
    A cracked engine mount, if not detected and 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.
    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, 
Inc. that allows them to produce technical data to use for Air Tractor, 
Inc. 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 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, Inc. following 
the instructions in the service information.

Costs of Compliance

    We estimate that this proposed AD would affect 368 airplanes in the 
U.S. registry.
    We estimate the following costs to do the proposed inspection of 
the engine mount for cracks:

[[Page 25794]]



----------------------------------------------------------------------------------------------------------------
                                                             Total cost per
             Labor cost                    Parts cost         airplane per    Total cost on U.S.  operators for
                                                               inspection             initial inspection
----------------------------------------------------------------------------------------------------------------
1.5 work hours x $80 per hour =      Not Applicable........            $120  368 x $120 = $44,160
 $120.
----------------------------------------------------------------------------------------------------------------

    We have no way of determining the number of airplanes that may need 
repair/replacement of the engine mount as a result of the proposed 
inspection. We have no way of determining the cost of an engine mount 
repair. To replace the engine mount would take 81 work hours at $80 per 
hour (estimated total labor = $6,480), parts cost of $3,982, and a 
total replacement cost of $10,462 per 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 5:00 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 adding the following new AD:

Air Tractor, Inc.: Docket No. FAA-2006-24228; Directorate Identifier 
2006-CE-22-AD.

Comments Due Date

    (a) We must receive comments on this proposed airworthiness 
directive (AD) action by June 27, 2006.

Affected ADs

    (b) None.

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 cracked engine mounts. 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.

What Must I do to Address This Problem?

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

------------------------------------------------------------------------
           Actions                 Compliance            Procedures
------------------------------------------------------------------------
(1) Visually inspect the      Initially inspect     Follow Snow
 engine mount for any cracks.  upon accumulating     Engineering Co.
                               4,000 hours time-in-  Service Letter
                               service (TIS) or      253, dated
                               within the next 100   December 12, 2005.
                               hours TIS after the
                               effective date of
                               this AD, whichever
                               occurs later,
                               unless already
                               done. Thereafter,
                               repetitively
                               inspect every 300
                               hours TIS.
(2) If you find any crack     Before further        For obtaining a
 damage, do one of the         flight after any      repair scheme:
 following:                    inspection required   Follow Snow
(i) Obtain an FAA-approved     by paragraph (e)(1)   Engineering Co.
 repair scheme from the        of this AD where      Service Letter
 manufacturer and              crack damage is       253, dated
 incorporate this repair       found. If you         December 12, 2005.
 scheme; or                    repair the cracked    For the
(ii) Replace the engine        engine mount, then    replacement: The
 mount with a new engine       continue to           maintenance manual
 mount.                        reinspect at          includes
                               intervals not to      instructions for
                               exceed 300 hours      the replacement.
                               TIS, unless the
                               repair scheme
                               states differently.
                               If you replace the
                               engine mount, then
                               initially inspect
                               upon accumulating
                               4,000 hours TIS and
                               repetitively at
                               intervals not to
                               exceed 300 hours
                               TIS.

[[Page 25795]]

 
(3) Report any cracks that    Within the next 10    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 10    approved the
 Include in your report:       days after the        information
(i) Airplane serial number;    effective date of     collection
(ii) Airplane and engine       this AD, whichever    requirements
 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.

Related Information

    (g) To get copies of the documents 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://dms.dot.gov. The 
docket number is Docket No. FAA-2006-24228; Directorate Identifier 
2006-CE-22-AD.

    Issued in Kansas City, Missouri, on April 26, 2006.
John R. Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E6-6584 Filed 5-1-06; 8:45 am]
BILLING CODE 4910-13-P