AD 2010-13-09

This AD becomes effective July 26, 2010.

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.

Antonio Cancelliere, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: antonio.cancelliere@faa.gov; telephone (781) 238-7751; fax (781) 238-7199.

The FAA proposed to amend 14 CFR part 39 with a proposed AD. The proposed AD applies to CFM International, S.A. CFM56-5, -5B, and -7B series turbofan engines. We published the proposed AD in the Federal Register on March 18, 2010 (75 FR 13045). That action proposed to require removing from service, nine stage 3 LPT disks, identified by S/N.

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.

We provided the public the opportunity to participate in the development of this AD. We have considered the comments received. Two commenters support the proposal as written.

One commenter, CFM International, S.A., requests that we remove the reference to the Airbus A340 airplane from the applicability paragraph, as the engines used on that airplane are CFM56-5C engines, and use a different disk P/N not affected by this AD.

We agree. We removed the A340 reference from the AD.

CFM International, S.A., requests that we reference the disk part number of 336-002-006-0, along with the affected disk serial numbers, in the applicability paragraph to help identify the parts to be removed.

We agree. We added the disk part number to the applicability paragraph.

CFM International, S.A., requests clarification of the applicability paragraph that none of these affected disk S/Ns were originally installed on any CFM56-5 turbofan engines, however, that disk P/N is certified for use on CFM56-5 engines.

We agree and changed the applicability paragraph.

CFM International, S.A., requests that we reference the EASA related AD in our AD.

We agree and added a reference to EASA AD 2009-0270 in the AD.

We have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

We estimate that this AD will affect two engines installed on airplanes of U.S. registry. The pro-rated cost of the replacement parts is $40,375 per engine. We estimate that no additional labor costs will be incurred to perform the required disk removals, because the removals will be done at time of engine shop visit. Based on these figures, we estimate the total cost of the AD to U.S. operators to be $80,750.

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 have 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 summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary at the address listed under ADDRESSES.

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration 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 airworthiness directive: