AD 2006-20-10

We are adopting a new airworthiness directive (AD) for certain Air Tractor, Inc. (Air Tractor) Models AT-802 and AT-802A airplanes. This AD requires you to repetitively inspect the attach angles on the firewall mounted hopper rinse tank shelf for damage and/or cracks and replace damaged and/or cracked attach angles with steel attach angles. Replacing the attach angles with steel attach angles terminates the repetitive inspection requirement. Reports of an uncommanded change in the engine power setting caused by separation of the hopper rinse tank shelf from the firewall prompted this AD. We are issuing this AD to detect and correct damage and/or cracks in the attach angles on the firewall mounted hopper rinse tank shelf, which could result in failure of the attach angles. This failure could lead to shelf movement under maneuver load and shifting of the engine power cables, which could result in an uncommanded engine power setting change.

Final rule.

2006-20-10 Air Tractor, Inc.: Amendment 39-14779; Docket No. FAA- 2006-24710; Directorate Identifier 2006-CE-29-AD.

Effective Date

(a) This AD becomes effective on November 3, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Models AT-802 and AT-802A airplanes, all serial numbers beginning with 802/802A-0001 through 802/802A-0219, that are certificated in any category.

Unsafe Condition

(d) This AD results from reports of an uncommanded change in engine power setting caused by separation of a hopper rinse tank shelf from the firewall. We are issuing this AD to detect and correct damage and/or cracks in the attach angles on the firewall mounted hopper rinse tank shelf, which could result in failure of the attach angles. This failure could lead to shelf movement under maneuver load and shifting of the engine power cables, which could result in an uncommanded engine power setting change.

Compliance

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

Actions
Compliance
Procedures
(1) Visually inspect the three attach angles on the firewall mounted hopper rinse tank shelf for damage and/or cracks.
Initially inspect within the next 100 hours time-in-service (TIS) after November 3, 2006 (the effective date of this AD). If no damage and/or cracks are found, repetitively inspect thereafter at intervals not to exceed 100 hours TIS. Replacing all three attach angles with steel attach angles, part number (P/N) 60568-3 (or FAA-approved equivalent P/N), terminates the repetitive inspection requirement of this AD.
Follow Snow Engineering Co. Service Letter #248, dated August 31, 2005.
(2) If you find any damage and/or cracks on any of the three attach angles during any inspection required in paragraph (e)(1) of this AD, replace all three attach angles with steel attach angles, P/N 60568-3 (or FAA-approved equivalent P/N).
Before further flight after the inspection in which damage and/or cracks are found. Replacing all three attach angles with steel attach angles, P/N 60568-3 (or FAA-approved equivalent P/N), terminates the repetitive inspection requirement of paragraph (e)(1) of this AD.
Follow Snow Engineering Co. Service Letter #248, dated August 31, 2005.
(3) You may replace the aluminum attach angles on the firewall mounted hopper rinse tank shelf with steel attach angles, P/N 60568-3 (or FAA-approved equivalent P/N), at any time to terminate the repetitive inspections required in paragraph (e)(1) of this AD.
As of November 3, 2006 (the effective date of this AD).
Follow Snow Engineering Co. Service Letter #248, dated August 31, 2005.
(4) Do not install aluminum attach angles on the hopper rinse tank shelf attach angles.
As of November 3, 2006 (the effective date of this AD).
Not applicable.

(f) 14 CFR 21.303 allows for replacement parts through parts manufacturer approval (PMA). The phrase "or FAA-approved equivalent P/N" in this AD is intended toallow for the installation of parts approved through identicality to the design of the replacement parts. Equivalent replacement parts to correct the unsafe condition under PMA (other than identicality) may also be installed provided they meet current airworthiness standards, which include those actions cited in this AD.

Alternative Methods of Compliance (AMOCs)

(g) 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; fax: (210) 308-3370, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19.

Material Incorporated by Reference

(h) You must do the actions required by this AD following the instructions in Snow Engineering Co. Service Letter 248, dated August 31, 2005. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. To get a copy of this service information, contact Air Tractor Inc., P.O. Box 485, Olney, Texas 76374; telephone: (940) 564-5616; fax: (940) 564-5612. To review copies of this service information, go to the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, go to: http://www.archives.gov/federal--register/code--of--federal-- regulations/ibr--locations.html or call (202) 741-6030. 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 20590-0001 or on the Internet at http://dms.dot.gov. The docket number is FAA- 2006-24710; Directorate Identifier 2006-CE-29-AD.

Discussion

On June 13, 2006, 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-802 and AT-802A airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on June 20, 2006 (71 FR 35398). The NPRM proposed to require you to repetitively inspect the attach angles on the firewall mounted hopper rinse tank shelf for damage and/or cracks and replace damaged and/or cracked attach angles. Replacing the attach angles with steel attach angles, part number 60568-3, would terminate the proposed repetitive inspection requirement.

Comments

We provided the public the opportunity to participate in developing this AD. We received one comment from Carroll Communications. The comment is in reference to wind turbine radar interference.
We determined the comment is not relevant to this AD. We are not changingthe final rule AD action based on the comment.

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:
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.

Costs of Compliance

We estimate that this AD affects 219 airplanes in the U.S. registry.
We estimate the following costs to do the inspection:

Labor Cost
Parts Cost
Total Cost Per Airplane
Total Cost on U.S. Operators
1 work-hour X $80 an hour = $80.
Not applicable.
$80.
$80 X 219 = $17,520.

We estimate the following costs to do any necessary replacements that will be required based on the results of the inspection. We have no way of determining the number of airplanes that may need this replacement:

Labor Cost
Parts Cost
Total Cost For Each Airplane
3 work-hours X $80 an hour = $240.
$105.
$240 + $105 = $345.

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.

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 addresslisted under ADDRESSES. Include "Docket No. FAA-2006- 24710; Directorate Identifier 2006-CE-29-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
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
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. FAA amends Sec. 39.13 by adding the following new AD: