GE reported that while recertifying a non-GE repair shop, they found the shop's process for coating dovetail slots with a Cu-Ni-In thermal coating did not meet the standard requirements of GE Substantiation Requirements Repair Document No. RSS-012-S2. Further investigation by GE identified twelve affected stage 1 fan disks. We discussed the issue with GE and the repair shop, and we agreed to allow the repair shop to strip, inspect, and recoat the 12 disks instead of issuing an AD to require the actions. The repair shop has stripped, inspected, and recoated 11 of the 12 disks. They have not been able to get the final stage 1 disk, P/N 1703M78P11, SN RPMDA662, to strip, inspect, and recoat that disk and it remains in service. This condition, if not corrected, could result in an uncontained release of multiple fan blades, and possible damage to the airplane
Relevant Service Information
We have reviewed and approved the technical contents of GE Service Bulletin (SB) No. CF6-80C2 S/B 72-1121, dated January 23, 2004, that references procedures for stripping, inspecting, and recoating the affected stage 1 fan disks.
Differences Between This AD and the Service Information
GE SB No. CF6-80C2 S/B 72-1121, dated January 23, 2004, recommends performing the actions within 3,500 cycles-since-last Cu-Ni-In thermal spray coating of the dovetail slots. This AD requires performing the actions within 3,500 cycles-since-last Cu-Ni-In thermal spray coating of the dovetail slots, but before March 31, 2008.
FAA's Determination and Requirements of This AD
Although no airplanes that are registered in the United States use these GE CF6-80-C2B1 turbofan engines, the possibility exists that the engines could be used on airplanes that are registered in the United States in the future. The unsafe condition described previously is likely to exist or develop on other GE CF6-80C2B1 turbofan engines of the same type design. We are issuing this ADto prevent possible uncontained release of multiple fan blades, resulting in damage to the airplane. You must use the service information described previously to perform the actions required by this AD.
FAA's Determination of the Effective Date
Since there are currently no domestic operators of this engine model, notice and opportunity for public comment before issuing this AD are unnecessary. A situation exists that allows the immediate adoption of this regulation.
Comments Invited
This AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment. However, we invite you to send us any written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include "AD Docket No. FAA-2007-0193; Directorate Identifier 2007-NE-43-AD'' in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify it.
We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this AD. Using the search function of the DMS Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78).
Examining 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 the same as the Mail address provided in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.
Authority for This Rulemaking
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.
Regulatory Findings
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 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 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Under the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive: