AD 2008-21-08

This AD becomes effective on November 20, 2008.

On November 20, 2008, the Director of the Federal Register approved the incorporation by reference of Snow Engineering Co. Service Letter #247, revised June 2, 2008, listed in this AD.

As of December 21, 2006 (71 FR 66661, November 16, 2006), the Director of the Federal Register approved the incorporation by reference of Snow Engineering Co. Process Specification Number 145, dated December 6, 1991, listed in this AD.

For service information identified in this AD, contact Air Tractor, Inc., P.O. Box 485, Olney, Texas 76374; telephone: (940) 564-5616; facsimile: (940) 564-5612; E-mail: parts@airtractor.com; Web site: http://www.airtractor.com.

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. The docket number is FAA-2008-0749; Directorate Identifier 2008-CE-044-AD.

Andy McAnaul, Aerospace Engineer, 10100 Reunion Pl, San Antonio, Texas 78216; telephone: (210) 308-3365; fax: (210) 308-3370.

On July 1, 2008, 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 Models AT-402, AT-402A, and AT-402B airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on July 8, 2008 (73 FR 38933). The NPRM proposed to require you to repetitively visually inspect the rudder and vertical fin hinge attaching structure for loose fasteners and inspect the rudder or vertical fin skins, spars, hinges, or brackets for cracks and/or corrosion. This AD would also require you to replace any damaged parts found as a result of the inspections and install an external doubler at the upper rudder hinge. Installation of the external doubler at the upper rudder hinge is terminating action for the repetitive inspection requirements.

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.

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:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

We estimate that this AD affects 220 airplanes in the U.S. registry.

We estimate the following costs to do the inspection:

Any required replacements will vary depending upon the damage found, and any replacements required will vary based on the results of the inspection. Based on this, we have no way of determining the potential replacement costs for each airplane or the number of airplanes that will need the replacements based on the result of the inspections.

We estimate the following costs to do installation of the external doubler at the upper rudder hinge:

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.

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-2008-0749; Directorate Identifier 2008 CE-044-AD” in your request.

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:

1. The authority citation for part 39 continues to read as follows:

2. FAA amends § 39.13 by adding the following new AD: