FAA's Determination and Requirements of This AD

We are issuing this AD because we evaluated all the information and determined the unsafe condition described previously is likely to exist or develop on other products of the same type design. This AD supersedes AD 20030601 with a new AD that:

We are not retaining from AD 20030601 the provision to allow a limited time of continued operation beyond the safe life limit.

In preparing this rule, we contacted type clubs and aircraft operators to get technical information and information on operational and economic impacts. We did not receive any information through these contacts. If received, we would have included a discussion of any information that may have influenced this action in the rulemaking docket.

FAA's Determination of the Effective Date

Since an unsafe condition exists that requires the immediate adoption of this AD, we determined that notice and opportunity for public comment before issuing this AD are impracticable, and that good cause exists for making this amendment effective in fewer than 30 days. Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and an opportunity for public comment. We invite you to send any written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number ``FAA20080476; Directorate Identifier 2008CE018AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD. We will consider all comments received by the closing date and may amend the 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 AD.

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 that this AD: (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) 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.

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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 that contains the 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 (800) 6475527) 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.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:
PART 39AIRWORTHINESS 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) 20030601, Amendment 3913088 (68 FR 13221, March 19, 2003), and by adding a new AD to read as follows:
20080910 Air Tractor, Inc.: Amendment 3915491; Docket No. FAA 20080476; Directorate Identifier 2008CE018AD.
Effective Date
(a) This AD becomes effective on May 8, 2008.
Affected ADs
(b) This AD supersedes AD 20030601, Amendment 3913088.
Applicability
(c) This AD applies to the following airplanes that are certificated in any category:
(1) Models AT300, AT301, AT302, and AT400A airplanes, all serial numbers, that have aluminum spar caps;
(2) Models AT400 airplanes, serial numbers 4000244 through 4000415, that have aluminum spar caps; and
(3) Models AT300 and AT301 airplanes, all serial numbers that have aluminum spar caps and are or have been converted to turbine power.
Unsafe Condition
(d) This AD is the result of service reports and analysis done on wing lower spar caps of Air Tractor, Inc. airplanes. The actions specified by this AD are intended to prevent fatigue cracks from occurring in the wing lower spar cap before the established safe life is reached. Fatigue cracks in the wing lower spar cap, if not detected and corrected, could result in failure of the spar cap and lead to wing separation and loss of control.
Compliance
(e) To address this problem, you must do the following, unless already done:
(1) For all affected airplanes without steel web plates, part numbers (P/N) 209901 or 209902, or steel spar caps installed, eddycurrent inspect the left and right wing spar lower cap outboard holes for cracks following Snow Engineering Co. Process
Specification 197, revised June 4, 2002. Do the inspections at the following compliance times:
Initial compliance Repetitive Affected airplanes time compliance time (i) For all airplanes....... Initially inspect Repetitively inspect upon reaching 3,500 thereafter at total hours timein intervals not to service (TIS) on exceed 450 hours the wing spar lower TIS until the wing cap or within the spar center splice next 10 hours TIS joint modification after May 8, 2008 or the required (the effective date wing spar lower cap of this AD), replacement. After whichever occurs each replacement, later. initially inspect upon reaching 3,500 total hours TIS on either wing spar lower cap, and repetitively inspect thereafter at intervals not to exceed 450 hours TIS until the wing spar center splice joint modification or the required wing spar lower cap replacement. (ii) Airplanes that have had You may take credit Repetitively inspect an eddycurrent inspection for that thereafter at done on the wing spar lower inspection. intervals notto cap within the last 450 Continue with the exceed 450 hours hours TIS before the required repetitive TIS from the time effective date of this AD. inspection of the last intervals. inspection until the wing spar center splice joint modification or the required wing spar lower cap replacement. After each replacement, initially inspect upon reaching 3,500 total hours TIS on either wing spar lower cap, and repetitively inspect thereafter at intervals not to exceed 450 hours TIS until the wing spar center splice joint modification or the required wing spar lower cap replacement. (2) For all affected Models AT300 and AT301 airplanes with reciprocating engines, the 450hour repetitive inspections required in this AD are terminated after the wing spar center splice joint modification is incorporated in accordance with paragraph (g) of this AD or when the wing lower spar caps are replaced. The replacement specified in paragraph (f)(2) of this AD is still applicable.
(3) If cracks are found during any inspection required in paragraphs (e)(1)(i), (e)(1)(ii), or (g)(2) of this AD, replace the wing lower spar cap before further flight.
(f) Replace each wing lower spar cap in accordance with the applicable maintenance manual, as follows:
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Repetitive Initial replacement replacement/ Affected airplanes compliance time inspection compliance time (1) For all affected Models Upon reaching 5,000 Replace each time AT300 and AT301 airplanes total hours TIS on the safe life limit with reciprocating engines either wing spar of 5,000 total and that do not incorporate lower cap or within hours TIS on either the wing spar center splice the next 25 hours wing spar lower cap joint modification. TIS after April 4, is reached. After 2003 (the effective each replacement, date of AD 200306 inspect as 01), whichever specified in occurs later. paragraph (e)(1) of this AD until the wing spar center splice joint modification or the required wing spar lower cap replacement. (2) For all affected Models Upon reaching the Replace each time AT300 and AT301 airplanes safe life limit of the safe life limit with reciprocating engines 7,000 total hours of 7,000 total that do incorporate the TIS on either wing hours TIS on either wing spar center splice spar lower cap or wing spar lower cap joint modification done in within the next 25 is reached. After accordance paragraph (g) of hours TIS after each replacement, this AD. April 4, 2003 (the inspect as effective date of specified in AD 20030601), paragraph (e)(1) of whichever occurs this AD until the later. wing spar center splice joint modification or the required wing spar lower cap replacement. (3) For all affected AT302, Upon reaching 4,450 Replace each time AT400, and AT400A total hours TIS on the safe life limit airplanes with aluminum either wing spar of 4,450 total spar caps; and all affected lower cap or within hours TIS on the Models AT300 and AT301 the next 25 hours wing spar lower cap airplanes with aluminum TIS after April 4, is reached. After spar caps that are or have 2003 (the effective each replacement ever been converted to date of AD 200306 inspect as turbine power. 01), whichever specified in occurs later. paragraph (e)(1) of this AD until the required wing spar lower cap replacement. (g) For airplanes specified in paragraph (f)(1) of this AD, you may extend the safe life limit of the wing spar lower cap to 7,000 hours TIS by incorporating the wing spar center splice joint modification following the procedures in Snow Engineering Co. Service Letter 55, revised October 23, 2002; or Snow Engineering Co. Service Letter 55, revised October 4, 2004, with the following requirements:
(1) This modification must be done no earlier than 4,600 total hours TIS on the wing spar lower cap and no later than 5,000 total hours TIS on the wing spar lower cap.
(2) Immediately before incorporating the modification, you must do an eddycurrent inspection for cracks following Snow Engineering Co. Process Specification 197, revised June 4, 2002. (3) After each replacement, inspect as specified in paragraph (e)(1) of this AD until the wing spar center splice joint
modification or the required wing spar lower cap replacement. (h) Eddycurrent inspections required by this AD must be done by one of the following:
(1) A level 2 or 3 inspector certified in eddycurrent
inspection using the guidelines established by the American Society for Nondestructive Testing or NAS 410; or
(2) A person authorized to perform AD maintenance work and who has completed and passed the Air Tractor, Inc. training course on eddycurrent inspection on wing lower spar caps.

Note 1: We are not retaining from AD 20030601 the provision to allow a limited time of continued operation beyond the safe life limit provided parts are ordered, the replacement is scheduled, and repetitive inspections reveal no cracks. That provision was put in AD 20030601 to prevent airplanes from being inadvertently grounded if parts were not available. If parts availability were to ever become a problem in the future, the owner/operator could request an alternative method of compliance following the procedures in 14 CFR 39.19 and this AD.
(i) Report the results of any inspection required by this AD where cracks are found to the FAA.
(1) Submit this report within 10 days after the inspection. (2) Use the form (Figure 1 of this AD) and submit it to FAA, Fort Worth Airplane Certification Office (ACO), 2601 Meacham Boulevard, Fort Worth, Texas 761930150; telephone: (817) 2225156; facsimile: (817) 2225960.
(3) The Office of Management and Budget (OMB) approved the information collection requirements contained in this regulation under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and assigned OMB Control Number 21200056. BILLING CODE 491013P
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[GRAPHIC] [TIFF OMITTED] TR28AP08.001
BILLING CODE 491013C
Alternative Methods of Compliance (AMOCs)
(j) The Manager, Fort Worth ACO, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Rob Romero, Aerospace Engineer, FAA, Fort Worth ACO, 2601 Meacham Boulevard, Fort Worth, Texas 761930150; telephone: (817) 2225102; facsimile: (817) 222 5960; or Andrew McAnaul, Aerospace Engineer, ASW150 (c/o MIDO43), 10100 Reunion Place, Suite 650, San Antonio, Texas 78216; telephone: (210) 3083365; facsimile: (210) 3083370. 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.
(k) AMOCs approved for AD 20030601 are approved for this AD. [[Page 22800]]
Special Flight Permit
(l) Under 14 CFR part 39.23, we are limiting the special flight permits for this AD by the following conditions:
(1) Operate only 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 gforces.
(5) Avoid areas of turbulence.
(6) Plan the flight to follow the most direct route.
Material Incorporated by Reference
(m) You must use Snow Engineering Co. Service Letter
55, revised October 23, 2002; Snow Engineering Co. Service Letter 55, revised October 4, 2004; and Snow Engineering Co. Process Specification Number 197, revised June 4, 2002, 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 Snow Engineering Co. Service Letter 55, revised October 4, 2004, under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) On April 4, 2003, (68 FR 13221, March 19, 2003), the Director of the Federal Register approved the incorporation by reference of Snow Engineering Co. Service Letter 55, revised October 23, 2002, and Snow Engineering Process Specification Number 197, revised June 4, 2002.
(3) For service information identified in this AD, contact Tractor, Inc., P.O. Box 485, Olney, Texas 76374.
(4) 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 7416030, or go to: http://www.archives.gov/federal_register/code_ of_federal_regulations/ibr_locations.html.

Issued in Kansas City, Missouri, on April 18, 2008. David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. E89058 Filed 42508; 8:45 am]
BILLING CODE 491013P

FOR FURTHER INFORMATION CONTACT Rob Romero, Aerospace Engineer, FAA, Fort Worth Airplane Certification Office (ACO), 2601 Meacham Boulevard, Fort Worth, Texas 761930150; telephone: (817) 2225102; facsimile: (817) 2225960; or Andrew McAnaul, Aerospace Engineer, FAA, Fort Worth ACO (c/o MIDO43), 10100 Reunion Place, Suite 650, San Antonio, Texas 78216; telephone: (210) 3083365; facsimile: (210) 3083370.