[Federal Register Volume 72, Number 88 (Tuesday, May 8, 2007)]
[Rules and Regulations]
[Pages 25957-25960]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-8671]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-26775; Directorate Identifier 2007-CE-01-AD; 
Amendment 39-15042; AD 2007-10-01]
RIN 2120-AA64


Airworthiness Directives; Air Tractor, Inc. Model AT-602 
Airplanes

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

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
Air Tractor, Inc. (Air Tractor) Model AT-602 airplanes. This AD 
requires you to install access holes to do repetitive detailed visual 
inspections for cracks in the horizontal stabilizer brace tube 
assembly, and if any cracks are found as a result of a visual 
inspection, to replace

[[Page 25958]]

the horizontal stabilizer brace tube assembly with a new design 
horizontal stabilizer brace tube assembly. The installation of the new 
design horizontal stabilizer brace tube assembly is terminating action 
for the repetitive inspection requirement. This AD results from two 
reports of Model AT-602 airplanes with cracked horizontal stabilizer 
brace tube assemblies. We are issuing this AD to detect and correct 
cracks in the horizontal stabilizer brace tube assembly, which could 
result in failure of the horizontal stabilizer. This failure could 
affect the ability to control pitch with consequent loss of control.

DATES: This AD becomes effective on June 12, 2007.
    On June 12, 2007 the Director of the Federal Register approved the 
incorporation by reference of certain publications listed in this AD.

ADDRESSES: For service information identified in this AD, contact Air 
Tractor Inc., P.O. Box 485, Olney, Texas 76374; telephone: (940) 564-
5616; fax: (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 20590-001 or on the Internet at http://dms.dot.gov. The docket number is FAA-2006-26775; Directorate 
Identifier 2007-CE-01-AD.

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; fax: (210) 308-3370.

SUPPLEMENTARY INFORMATION: 

Discussion

    On January 31, 2007, we issued a proposal to amend part 39 of the 
Federal Aviation Regulations (14 CFR part 39) to include an AD that 
would apply to certain Air Tractor Model AT-602 airplanes. This 
proposal was published in the Federal Register as a notice of proposed 
rulemaking (NPRM) on February 6, 2007 (72 FR 5359). The NPRM proposed 
to require you to install access holes to do repetitive detailed visual 
inspections for cracks in the horizontal stabilizer brace tube 
assembly, and if any cracks are found as a result of a visual 
inspection, to replace the horizontal stabilizer brace tube assembly 
with a new design horizontal stabilizer brace tube assembly. The 
installation of the new design horizontal stabilizer brace tube 
assembly is terminating action for the repetitive inspection 
requirement.

Comments

    We provided the public the opportunity to participate in developing 
this AD. We received no comments on the proposal or on the 
determination of the cost to the public.

Conclusion

    We have carefully reviewed the available data and determined that 
air safety and the public interest require adopting the AD as proposed 
except for minor editorial corrections. We have determined that these 
minor corrections:
    <bullet> Are consistent with the intent that was proposed in the 
NPRM for correcting the unsafe condition; and
    <bullet> Do not add any additional burden upon the public than was 
already proposed in the NPRM.

Costs of Compliance

    We estimate that this AD affects 128 airplanes in the U.S. 
registry.
    We estimate the following costs to do the installation of access 
holes to do visual inspections:

----------------------------------------------------------------------------------------------------------------
                                                                                 Total cost per   Total cost on
                          Labor cost                              Parts cost        airplane      U.S. operators
----------------------------------------------------------------------------------------------------------------
1 work-hour x $80 per hour = $80.............................              $5              $85          $10,880
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do each visual inspection for 
cracks of the horizontal stabilizer brace tube assembly:

----------------------------------------------------------------------------------------------------------------
                                                                                                  Total cost on
                                                                                 Total cost per   U.S. operators
                          Labor cost                              Parts cost        airplane       for initial
                                                                                                    inspection
----------------------------------------------------------------------------------------------------------------
1 work-hour x $80 per hour = $80.............................  Not Applicable              $80          $10,240
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary replacement of 
the horizontal stabilizer brace tube assembly with a new design 
horizontal stabilizer brace tube assembly that will be required based 
on the results of the inspection or as the terminating action for the 
repetitive inspection requirement. We have no way of determining the 
number of airplanes that will need this replacement:

------------------------------------------------------------------------
                                                          Total cost per
              Labor cost                   Parts cost        airplane
------------------------------------------------------------------------
35 work-hours x $80 per hour = $2,800.            $896           $3,696
------------------------------------------------------------------------

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 AD.

[[Page 25959]]

Regulatory Findings

    We have 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 that 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 summary of the costs to comply with this AD (and 
other information as included in the Regulatory Evaluation) and placed 
it in the AD Docket. You may get a copy of this summary by sending a 
request to us at the address listed under ADDRESSES. Include ``Docket 
No. FAA-2006-26775; Directorate Identifier 2007-CE-01-AD'' in your 
request.

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 Federal Aviation Administration amends part 39 of the Federal 
Aviation Regulations (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. FAA amends Sec.  39.13 by adding the following new AD:

2007-10-01 Air Tractor Inc.: Amendment 39-15042; Docket No. FAA-
2006-26775; Directorate Identifier 2007-CE-01-AD.

Effective Date

    (a) This AD becomes effective on June 12, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Model AT-602 airplanes, all serial 
numbers through 602-0695 that:
    (1) Have horizontal stabilizer brace tube assembly, part number 
(P/N) 30012-7, installed; and
    (2) Are certificated in any category.

Unsafe Condition

    (d) This AD results from two reports of Model AT-602 airplanes 
with cracked horizontal stabilizer brace tube assemblies. We are 
issuing this AD to detect and correct cracks in the horizontal 
stabilizer brace tube assembly, which could result in failure of the 
horizontal stabilizer. This failure could affect the ability to 
control pitch with consequent loss of control.

Compliance

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

------------------------------------------------------------------------
             Actions                  Compliance          Procedures
------------------------------------------------------------------------
(1) Do the following:             Install the access  Follow Snow
(i) Install access holes for       holes and do the    Engineering Co.
 visual inspection of the P/N      initial             Service Letter
 30012-7, horizontal stabilizer    inspection upon     <greek-i>235,
 brace tube assembly.              accumulating        dated August 25,
(ii) Conduct a detailed visual     2,000 hours time-   2004, revised
 inspection for cracks in the P/   in-service (TIS)    October 24, 2006.
 N 30012-7 horizontal stabilizer   or within the
 brace tube assembly.              next 60 days
                                   after June 12,
                                   2007 (the
                                   effective date of
                                   this AD),
                                   whichever occurs
                                   later.
                                   Repetitively
                                   inspect
                                   thereafter at
                                   intervals not to
                                   exceed 100 hours
                                   TIS. Replacement
                                   of the P/N 30012-
                                   7 horizontal
                                   stabilizer brace
                                   tube assembly
                                   with a new design
                                   P/N 30766-1
                                   horizontal
                                   stabilizer brace
                                   tube assembly
                                   following
                                   paragraph (e)(2)
                                   of this AD is
                                   terminating
                                   action for the
                                   repetitive
                                   inspection
                                   requirement of
                                   this AD.
(2) Replace the P/N 30012-7       Before further      Follow Snow
 horizontal stabilizer brace       flight after any    Engineering Co.
 tube assembly with a new design   inspection          Service Letter
 P/N 30766-1 horizontal            required by         <greek-i>129A,
 stabilizer brace tube assembly.   paragraph (e)(1)    dated August 7,
                                   of this AD where    2004, revised
                                   cracks are found.   November 15,
                                   The installation    2005; Snow
                                   of a new design P/  Engineering Co.
                                   N 30766-1           Service Letter
                                   horizontal          <greek-i>235,
                                   stabilizer brace    dated August 25,
                                   tube assembly is    2004, revised
                                   terminating         October 24, 2006;
                                   action for the      and Snow
                                   repetitive          Engineering Co.
                                   inspection          Drill Template--
                                   requirement of      602, Drawing
                                   this AD.            Number SL129-602,
                                                       dated August 2,
                                                       2004.
(3) Do not install any P/N 30012- As of June 12,      Not Applicable.
 7 horizontal stabilizer brace     2007 (the
 tube assembly.                    effective date of
                                   this AD).
------------------------------------------------------------------------

Alternative Methods of Compliance (AMOCs)

    (f) The Manager, Fort Worth Airplane Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested using 
the procedures found in 14 CFR 39.19. Send information to ATTN: 
Andrew McAnaul, Aerospace Engineer, ASW-150 (c/o MIDO-43), 10100 
Reunion Place, Suite 650, San Antonio, Texas 78216; telephone: (210) 
308-3365; fax: (210) 308-3370. 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.

Related Information

    (g) 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; fax: (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-2006-26775; Directorate Identifier 
2007-CE-01-AD.

Material Incorporated by Reference

    (h) You must use Snow Engineering Co. Service Letter 
<greek-i>129A, dated August 7, 2004, revised November 15, 2005; Snow 
Engineering Co. Service Letter <greek-i>235, dated August 25, 2004, 
revised October 24, 2006; and Snow Engineering Co. Drill Template--
602, Drawing Number SL129-602, dated August 2, 2004, 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 Air 
Tractor Inc., P.O. Box

[[Page 25960]]

485, Olney, Texas 76374; telephone: (940) 564-5616; fax: (940) 564-
5612.
    (3) You may review copies at the FAA, Central Region, Office of 
the Regional Counsel, 901 Locust, Kansas City, Missouri 64106; or at 
the National Archives and Records Administration (NARA). For 
information on the availability of this material at NARA, call 202-
741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

    Issued in Kansas City, Missouri, on April 27, 2007.
David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-8671 Filed 5-7-07; 8:45 am]
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