AD 2006-24-11

This AD becomes effective on December 11, 2006.

As of December 11, 2006, the Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulation.

We must receive any comments on this AD by February 2, 2007.

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

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.

• Government-wide rulemaking web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.

• Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590-0001.

• Fax: (202) 493-2251.

• Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

To get the service information identified in this AD, contact Raytheon Aircraft Company (RAC), Post Office Box 85, Wichita, Kansas 67201-0085, Phone 1-800-429-5372 or 1-316-676-2000, Fax: 1-316-676-8745.

To view the comments to this AD, go to http://dms.dot.gov. The docket number is FAA-2006-26258; Directorate Identifier 2006-CE-67-AD.

Steven E. Potter, FAA, 1801 Airport Road, Wichita, Kansas 67209; telephone: (316) 946-4124; fax: (316) 946-4107.

Due to significant cracks found in the wing rear spar of RAC Model 1900D airplanes, we issued Emergency AD 2006-18-51 on August 31, 2006. AD 2006-18-51 required an immediate visual inspection of both the left and right wing rear spars near the outboard edge of the engine nacelle. This AD was then published in the Federal Register as Amendment 39-14757 (71 FR 52983, September 8, 2006).

Additional fatigue cracks in the affected area of the wing rear spar have been found since the AD 2006-18-51 inspections were performed. One of the airplanes had accumulated 168 hours time-in-service (TIS) since the visual inspections required by AD 2006-18-51 were done.

The FAA has determined a more rigorous and detailed inspection is necessary to find such fatigue cracks.

Cracking in the wing rear spar lower caps and adjacent structure, if not corrected, could result in wing failure. Such a wing failure could result in the wing separating from the airplane with consequent loss of control.

We reviewed Raytheon Aircraft Company Service Bulletin No. 57-3815, Issued: October, 2006. The service information describes procedures for the left and right rear wing spar lower cap inspection.

We are issuing this AD because we have evaluated all known and available 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 a rigorous and detailed inspection of the wing rear spar lower caps to find the fatigue cracks. The preparation and procedural requirements for these inspections are included in RAC Mandatory Service Bulletin 57-3815.

RAC is developing a modification that, if approved by the FAA, would terminate the repetitive inspection requirement of this AD. The FAA may take future rulemaking action on this subject.

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.

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-2006-26258; Directorate Identifier 2006-CE-67-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://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive concerning this AD.

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.

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.

You may examine the AD docket that contains the AD, the regulatory evaluation, any comments received, and other information on the Internet at http://dms.dot.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) 647-5227) is located at the street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

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

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):