AD 2009-03-05

This AD becomes effective March 27, 2009. The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of March 27, 2009.

The Docket Operations office is located at Docket Management Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-0001.

Ian Dargin, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park; Burlington, MA 01803; e-mail: ian.dargin@faa.gov; telephone (781) 238-7178; fax (781) 238-7199.

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 June 25, 2008, (73 FR 35982). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

PW206 and PW207 compressor turbine (CT) disc bore areas may experience impact damage resulting from bending or fracture of the CT disc retaining nut. Damage of the CT disc bore area can reduce LCF capabilities of the CT disc, resulting in disc fracture.

Under high centrifugal loads, the CT disk retaining nut castellations might bend outward, then contact and mark the CT disk internal bore. Worldwide, a total of five events of CT nut damage and associated damage to the CT disk bore have been reported. A total of 195 out of 402 engines in the U.S. fleet have been inspected with two cases of CT nut damage and no findings of disk damage, to date. 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.

Although the MCAI allows use of future revisions of PWC ASB PW200-72-A28280, we require the use of Revision 4 of that ASB.

Although the MCAI has a March 21, 2008 compliance date, we have changed the final rule from a December 21, 2008 compliance date to within 30 days after the effective date of the AD. This is based on a review of the risk assessment and the fleet inspection results to date.

We estimate that this AD will affect 402 engines of U.S. registry. We also estimate that it will take 8 work-hours per product to comply with this AD. The average labor rate is $80 per work-hour. Required parts will cost about $500 per product. We expect that 1 disk on the remaining 207 engines will be replaced, at an estimated cost of $20,000. Based on these figures, we estimate the cost of the AD to U.S. operators to be $478,280. Our cost estimate is exclusive of possible warranty coverage.

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 this AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone (800) 647-5527) is provided 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 adding the following new AD: