E9-11902. Airworthiness Directives; Air Tractor, Inc. Models AT-400, AT-400A, AT-402, AT-402A, AT-402B, AT-502, AT-502A, AT-502B, AT-503A, AT-602, AT-802, and AT-802A Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

We are adopting a new airworthiness directive (AD) to supersede AD 2008-10-12, which applies to certain Air Tractor, Inc. AT-400, AT-500, AT-600, and AT-800 series airplanes. AD 2008-10-12 currently requires repetitively inspecting the engine mounts for cracks, repairing any crack damage found, and installing gussets as a terminating action for the repetitive inspections. This AD results from a report of a Model AT-602 airplane with a crack completely through the gusset that was installed as required in AD 2008-10-12. Consequently, this AD would require you to continue repetitively inspecting the engine mounts for cracks for all previously affected Air Tractor, Inc. AT-400, AT-500, AT-600, and AT-800 series airplanes with or without gussets installed, and repairing any crack damage found. We are issuing this AD to detect and correct cracks in the engine mount, which could result in failure of the engine mount. This failure could lead to separation of the engine from the airplane.

DATES:

This AD becomes effective on June 1, 2009.

As of June 12, 2008 (73 FR 25967, May 8, 2008), the Director of the Federal Register approved the incorporation by reference of Snow Engineering Co. Service Letter #253, Rev. C, dated April 17, 2008, listed in this AD.

We must receive any comments on this AD by July 21, 2009.

ADDRESSES:

Use one of the following addresses to comment on this AD.

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

To get the service information identified in this AD, contact Air Tractor, Inc., P.O. Box 485, Olney, Texas 76374; telephone: [phone]; fax: [phone]; Internet: http://www.airtractor.com.

To view the comments to this AD, go to http://www.regulations.gov. The docket number is FAA-2009-0473; Directorate Identifier 2009-CE-027-AD.

FOR FURTHER INFORMATION CONTACT:

Andy McAnaul, Aerospace Engineer, FAA, San Antonio MIDO-43, 10100 Reunion Pl., Ste. 650, San Antonio, Texas 78216, telephone: [phone], fax: [phone]; e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

Discussion

On April 30, 2008, we issued AD 2008-10-12, Amendment 39-15518 (73 FR 25967) on certain Air Tractor, Inc. AT-400, AT-500, AT-600, and AT-800 series airplanes to supersede AD 2007-13-17.

AD 2007-13-17 required 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.

AD 2008-10-12 currently:

• Retains the inspection actions of AD 2007-13-17 for Models AT-602, AT-802, and AT-802A airplanes, including the compliance times and effective dates;
• Establishes new inspection actions for the AT-400 and AT-500 series airplanes;
• Incorporates a mandatory terminating action for all affected airplanes by installing gussets; and
• Terminates the reporting requirement of AD 2007-13-17.

Since issuing AD 2008-10-12, we received a report of a Model AT-602 airplane with a crack in the engine mount and completely through the gusset that was installed as a terminating action as required in AD 2008-10-12. This engine mount was reported as having a crack that was repaired as part of the gusset installation. The mount reportedly accumulated approximately 1,100 hours time-in-service since being modified with the gusset.

Air Tractor, Inc. believes that the crack may have been improperly repaired during installation of the gusset. Additional procedures may be necessary to adequately address inspection and repair of cracked engine mounts and assure proper installation of the gussets.

This condition, if not corrected, could result in failure of the engine mount. This failure could lead to separation of the engine from the airplane.

Relevant Service Information

Snow Engineering Co. Service Letter #253, Rev. C, dated April 17, 2008, specified in AD 2008-10-12 is still valid for this AD.

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 requires repetitively inspecting the engine mounts for cracks and repairing any crack damage found.

Air Tractor is reviewing the information related to the occurrences referenced in this AD and may develop additional procedures to adequately address inspection and repair of cracked engine mounts and assure proper installation of the gussets that, when incorporated, would eliminate the need for the repetitive inspections required by this AD. The FAA will review any modification that is developed, determine whether it would eliminate the need for the requirements of this action, and then determine whether additional AD action is necessary.

FAA's Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because cracks in the engine mounts could result in failure of the engine mount. Such failure could lead to separation of the engine from the airplane. Therefore, 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 “FAA-2009-0473; Directorate Identifier 2009-CE-027-AD” 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.

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 [phone]) 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 39—AIRWORTHINESS DIRECTIVES

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

Authority: 49 U.S.C. 106(g), 40113, 44701.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by removing Airworthiness Directive (AD) 2008-10-12; Amendment 39-15518 ( 73 FR 25967, May 8, 2008), and by adding a new AD to read as follows:

2009-11-05 Air Tractor, Inc.: Amendment 39-15915; Docket No. FAA-2009-0473; Directorate Identifier 2009-CE-027-AD.

Effective Date

(a) This AD becomes effective on June 1, 2009.

Affected ADs

(b) This AD supersedes AD 2008-10-12; Amendment 39-15518.

Applicability

(c) This AD applies to the following airplane models and serial numbers that are certificated in any category:

Models	Serial Nos.
AT-400, AT-400A, AT-402, AT-402A, and AT-402B	−0001 through −1175.
AT-502, AT-502A, AT-502B, and AT-503A	−0001 through −2597.
AT-602	−0001 through −1141.
AT-802 and AT-802A	−0001 through −0227.

Unsafe Condition

(d) This AD is the result of a report of a Model AT-602 airplane with a crack completely through the gusset that was installed as required in AD 2008-10-12. 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.

Compliance

(e) Inspect the engine mount as follows using the service information in paragraph (i) of this AD:

Models	Compliance time without Gussets installed	Compliance time with Gussets installed
(1) For all Models AT-400, AT-400A, AT-402, AT-402A, AT-402B, AT-502, AT-502B, and AT-503A airplanes	Initially and repetitively as follows: (i) With less than 5,000 hours time-in-service (TIS) on the airplane: Initially within the next 12 months after June 12, 2008 (the effective date of AD 2008-10-12). Repetitively thereafter at intervals not to exceed every 12 months until accumulating 5,000 hours TIS;	Initially and repetitively as follows: (A) With less than 5,000 hours TIS on the airplane: Initially within the next 12 months after June 1, 2009 (the effective date of this AD). Repetitively thereafter at intervals not to exceed every 12 months until accumulating 5,000 hours TIS;
	(ii) With 5,000 hours TIS or more on the airplane: Initially upon accumulating 5,000 hours TIS on the airplane or within the next 10 hours TIS after June 1, 2009 (the effective date of this AD), or within the next 100 hours TIS from the last inspection performed, whichever occurs later. Repetitively thereafter at intervals not to exceed every 100 hours TIS.	(B) With 5,000 hours TIS or more on the airplane: Initially upon accumulating 5,000 hours TIS on the airplane or within the next 10 hours TIS after June 1, 2009 (the effective date of this AD), or within the next 100 hours TIS from the last inspection performed, whichever occurs later. Repetitively thereafter at intervals not to exceed every 100 hours TIS.
(2) AT-502A	(i) With less than 5,000 hours TIS on the airplane: Initially upon accumulating 1,300 hours TIS on the airplane or within the next 100 hours TIS after June 12, 2008 (the effective date of AD 2008-10-12), whichever occurs later. Repetitively thereafter at intervals not to exceed every 300 hours TIS.	(i) With less than 5,000 hours TIS on the airplane: Initially upon accumulating 1,300 hours TIS on the airplane or within the next 100 hours TIS after June 1, 2009 (the effective date of this AD), whichever occurs later. Repetitively thereafter at intervals not to exceed every 300 hours TIS.
	(ii) With 5,000 hours TIS or more on the airplane: Initially upon accumulating 5,000 hours TIS on the airplane or within the next 10 hours TIS after June 1, 2009 (the effective date of this AD), or within the next 100 hours TIS from the last inspection performed, whichever occurs later. Repetitively thereafter at intervals not to exceed every 100 hours TIS.	(ii) With 5,000 hours TIS or more on the airplane: Initially upon accumulating 5,000 hours TIS on the airplane or within the next 10 hours TIS after June 1, 2009 (the effective date of this AD), or within the next 100 hours TIS from the last inspection performed, whichever occurs later. Repetitively thereafter at intervals not to exceed every 100 hours TIS.
(3) AT-602, AT-802, and AT-802A	(i) With less than 5,000 hours TIS on the airplane: Initially upon accumulating 1,300 hours TIS on the airplane or within the next 100 hours TIS after August 10, 2007 (the effective date of AD 2007-13-17), whichever occurs later. Repetitively thereafter at intervals not to exceed every 300 hours TIS.	(i) With less than 5,000 hours TIS on the airplane: Initially upon accumulating 1,300 hours TIS on the airplane or within the next 100 hours TIS after June 1, 2009 (the effective date of this AD), whichever occurs later. Repetitively thereafter at intervals not to exceed every 300 hours TIS.
	(ii) With 5,000 hours TIS or more on the airplane: Initially upon accumulating 5,000 hours TIS on the airplane or within the next 10 hours TIS after June 1, 2009 (the effective date of this AD), or within the next 100 hours TIS from the last inspection performed, whichever occurs later. Repetitively thereafter at intervals not to exceed every 100 hours TIS.	(ii) With 5,000 hours TIS or more on the airplane: Initially upon accumulating 5,000 hours TIS on the airplane or within the next 10 hours TIS after June 1, 2009 (the effective date of this AD), or within the next 100 hours TIS from the last inspection performed, whichever occurs later. Repetitively thereafter at intervals not to exceed every 100 hours TIS.

(f) For all airplanes: Before further flight after any inspection required by paragraph (e)(1), (e)(2), and (e)(3) of this AD where crack damage is found, replace with a new engine mount or repair the engine mount.

(1) If choosing repair, return cracked mounts to Air Tractor, Inc. for repair or obtain FAA-approved written repair instructions coordinated with Air Tractor, Inc. before starting the repair.

(2) Contact Air Tractor, Inc., P.O. Box 485, Olney, Texas 76374; telephone: [phone]; fax: [phone]; Internet: http://www.airtractor.com, for specific FAA-approved repair/replacement instructions.

Alternative Methods of Compliance (AMOCs)

(g) 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: Andy McAnaul, Aerospace Engineer, ASW-150, FAA San Antonio MIDO-43, 10100 Reunion Place, Suite 650, San Antonio, Texas 78216; phone: [phone]; fax: [phone]. 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.

(h) AMOCs approved for AD 2008-10-12 are not approved for this AD.

Material Incorporated by Reference

(i) You must use Snow Engineering Co. Service Letter #253, Rev. C, dated April 17, 2008, to do the actions required by this AD, unless the AD specifies otherwise.

(1) As of June 12, 2008 (73 FR 25967), the Director of the Federal Register approved the incorporation by reference of Snow Engineering Co. Service Letter #253, Rev. C, dated April 17, 2008, 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 485, Olney, Texas 76374; telephone: [phone]; fax: [phone].

(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 May 15, 2009.

Scott A. Horn,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.