AD 2013-05-19

This AD becomes effective April 24, 2013.

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.

Frederick Zink, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; email: frederick.zink@faa.gov; telephone: 781-238-7779; 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 November 13, 2012 (77 FR 67582). That NPRM proposed to correct an unsafe condition for the specified products. The Mandatory Continuing Airworthiness Information states:

The results of a recent quality review of low pressure turbine (LPT) stage 1 static air seal and high pressure turbine (HPT) stage 1 air seal support bolts identified that, before installation, those bolts may have not been inspected. As a consequence, bolts with reduced material properties may have been installed in some engines.

This condition, if not detected and corrected, could lead to failure of a bolt, potentially causing turbine disc fracture and release of high-energy debris, possibly resulting in damage to the aeroplane and/or injury to the occupants.

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM (77 FR 67582, November 13, 2012). However, we changed paragraph (e) of this AD by removing the reporting requirement because that requirement is not necessary to correct the unsafe condition.

We reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed (77 FR 67582, November 13, 2012).

Based on the service information, we estimate that this AD affects about 20 engines of U.S. registry. We also estimate that it will take about 4 hours per product to comply with this AD. The average labor rate is $85 per hour. Required parts will cost about $1,848 per engine. Based on these figures, we estimate the cost of the AD on U.S. operators to be $43,760.

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);

3. Will not affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction, and

4. 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 (phone: (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: