E7-22922. Airworthiness Directives; General Electric Company (GE) CF6-80C2B1 Turbofan Engine

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for a GE CF6-80C2B1 turbofan engine, serial number (SN) 690203, with fan disk, part number (P/N) 1703M78P11, SN RPMDA662, installed. This AD requires stripping of thermal spray coating, inspection of dovetail slots, and reapplication of thermal spray coating on certain stage 1 fan disks. This AD results from a report that a repair shop did not meet the process requirements when applying copper-nickel-indium (Cu-Ni-In) thermal coating to certain stage 1 fan disks. We are issuing this AD to prevent possible uncontained release of multiple fan blades, resulting in damage to the airplane.

DATES:

This AD becomes effective January 2, 2008. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of January 2, 2008.

We must receive any comments on this AD by January 28, 2008.

ADDRESSES:

Use one of the following addresses to comment on this AD:

• Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: U.S. Docket Management Facility, Department of Transportation, 1200 New Jersey Avenue, SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-0001.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Fax: [phone].

Contact General Electric Company via Lockheed Martin Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 45215, telephone [phone], fax [phone], for the service information identified in this AD.

FOR FURTHER INFORMATION CONTACT:

James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone: [phone], fax: [phone].

SUPPLEMENTARY INFORMATION:

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 AD to 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 [phone]) 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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by adding the following new airworthiness directive:

2007-24-07 General Electric Company: Amendment 39-15273. Docket No. FAA-2007-0193; Directorate Identifier 2007-NE-43-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective January 2, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to GE CF6-80C2B1 turbofan engine, serial number 690203, with fan disk, part number (P/N) 1703M78P11, SN RPMDA662, installed. This engine is installed on, but not limited to, a Boeing 747-300 airplane.

Unsafe Condition

(d) This AD results from a report that a repair shop did not meet the process requirements when applying copper-nickel-indium (Cu-Ni-In) thermal coating to certain stage 1 fan disks. We are issuing this AD to prevent possible uncontained release of multiple fan blades, resulting in damage to the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within 3,500 cycles-since-last Cu-Ni-In thermal spray coating of the dovetail slots, but no later than March 31, 2008, unless the actions have already been done.

Stripping, Inspecting and Recoating the Stage 1 Fan Disk

(f) Strip the Cu-Ni-In thermal coating from the pressure faces and slot bottoms of the stage 1 fan disk, and perform a microstructure evaluation. Use 3.A.(2)(a) through 3.A.(2)(b) of GE Service Bulletin (SB) No. CF6-80C2 S/B 72-1121, dated January 23, 2004, to strip the thermal coating and perform the microstructure evaluation.

(g) Ultrasonic inspect, fluorescent penetrant inspect, and eddy current inspect stage 1 fan disk. Use 3.A.(2)(c) of GE SB No. CF6-80C2 S/B 72-1121, dated January 23, 2004, to inspect the disk.

(h) Apply Cu-Ni-In thermal coating to the pressure faces and slot bottoms of the stage 1 fan disks, using 3.A.(2)(d) of GE SB No. CF6-80C2 S/B 72-1121, dated January 23, 2004.

Alternative Methods of Compliance

(i) The Manager, Engine Certification Office, has the authority to approve alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19.

Related Information

(j) Contact James Lawrence, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone: [phone], fax: [phone], for more information about this AD.

Material Incorporated by Reference

(k) You must use GE Service Bulletin No. CF6-80C2 S/B 72-1121, dated January 23, 2004, to perform the actions required by this AD. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact General Electric Company via Lockheed Martin Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 45215, telephone [phone], fax [phone], for a copy of this service information. You may review copies at the FAA, New England Region, 12 New England Executive Park, Burlington, MA; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Issued in Burlington, Massachusetts, on November 15, 2007.

Peter A. White,

Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service.