AD 2008-24-09

This AD becomes effective January 2, 2009.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of January 2, 2009.

You may examine the AD docket on the Internet at http://www.regulations.gov or in person at the U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC.

Vladimir Ulyanov, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 227-1138; fax (425) 227-1149.

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM was published in the Federal Register on August 26, 2008 (73 FR 50256) and proposed to supersede AD 2007-08-05, Amendment 39-15022 (72 FR 18563, April 13, 2007). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

An A330 operator reported a shroud box bottom panel missing during a routine inspection. The same panel detached from an A330 aircraft during take-off, causing damage to the surrounding structure and to the Trimmable Horizontal Stabilizer (THS) tip fairing.

The inspection indicated the blind rivets used to attach the panel worked loose causing fatigue damage with crack propagation through the fastener line resulting in panel detachment.

To avoid potential injuries to persons on ground, Airworthiness Directive (AD) 2006-0107 [which corresponds with FAA AD 2007-08-05] mandated a one time detailed visual inspection of the shroud box bottom panel.

Further to issuance of AD 2006-0107, three additional events of panel loss have been experienced on in service aircraft already inspected in accordance with the AD requirements and no findings. Thus, it has been decided to delete this one time detailed visual inspection and to mandate a modification which prevents such unsafe condition. Therefore, the present AD supersedes EASA AD 2006-0107 and mandates the installation of a bolted shroud box bottom panel instead of blind riveted metallic design.

The modification includes doing all applicable related investigative and corrective actions. The related investigative action is an inspection to detect cracks of the shroud box hole. The corrective action is repairing any cracked shroud box hole. The applicability of the MCAI has been revised; certain airplanes have been removed and others added. You may obtain further information by examining the MCAI in the AD docket.

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

We reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have required different actions in this AD from those in the MCAI in order to follow our FAA policies. Any such differences are highlighted in a NOTE within the AD.

We estimate that this AD will affect about 34 products of U.S. registry. We also estimate that it will take about 20 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $80 per work-hour. Required parts will cost about $990 per product. Where the service information lists required parts costs that are covered under warranty, we have assumed that there will be no charge for these parts. As we do not control warranty coverage for affected parties, some parties may incur costs higher than estimated here. Based on these figures, we estimate the cost of this AD to the U.S. operators to be $88,060, or $2,590 per product.

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 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 regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket.

You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains the NPRM, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone (800) 647-5527) is 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 amends 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 removing Amendment 39-15022 (72 FR 18563, April 13, 2007) and adding the following new AD: