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Proposed Rule

Airworthiness Directives; General Electric Company CF6 Series Turbofan Engines

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) for General Electric (GE) CF6-45/-50 series and CF6-80A series turbofan engines with certain part number (P/N) side links of the five-link forward mount assembly installed. That AD currently requires an initial and repetitive visual inspection of the side links for cracks, and stripping and reapplying the Sermetel W coating on the side link at every exposure of the side link. That AD also requires replacing the side links and pylon attachment bolts, and inspecting the fail-safe bolt and platform lug if the side links are cracked. This proposed AD would continue to require those same inspections and stripping and reapplying the Sermetel W coating, and would add two part numbers to the applicability. This proposed AD results from a review of the inspection program, which revealed that GE had omitted two affected part numbers from the applicability. We are proposing this AD to prevent failure of the side links and possible engine separation from the airplane.

DATES:

We must receive any comments on this proposed AD by February 11, 2011.

ADDRESSES:

Use one of the following addresses to comment on this proposed AD.

  • Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
  • Mail: Docket Management Facility, U.S. 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: (202) 493-2251.
Start Further Info

FOR FURTHER INFORMATION CONTACT:

Tomasz Rakowski, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; telephone (781) 238-7735; fax (781) 238-7199.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2010-1151; Directorate Identifier 95-ANE-10-AD” in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

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 proposed AD. Using the search function of the Web site, anyone can find and read the comments in any of our dockets, including, if provided, 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 proposed 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.Start Printed Page 77571

Discussion

The FAA proposes to amend 14 CFR part 39 by superseding AD 2006-12-24, Amendment 39-14650 (71 FR 34807, June 16, 2006). That AD requires inspecting and stripping and reapplying the Sermetel W coating on the side links every time one or more of the bolts attaching the side link to the fan frame—front high-pressure compressor case or the bolt attaching the side link to the mount platform are removed. That AD resulted from a report of a cracked side link found during a routine inspection at a shop visit in 2006. That condition, if not corrected, could result in failure of the side links and possible engine separation from the airplane.

Actions Since AD 2006-12-24 Was Issued

Since that AD was issued, GE performed an evaluation of the inspection program and determined that they had omitted the P/Ns for two side links that could be installed on CF6-45/-50 series and CF6-80A series engines. GE introduced those P/N side links in 2000. The age of those side links means that they might have experienced only two shop visits (the average time between shop visits is about four years) since they were put into service. Also, about 50 percent of the new side links are spare parts and they might not be installed on any engines in service yet. Because of those conditions, we haven't received any reports of cracks in the new P/N links. However, due to the similarity in design between these additional parts and the parts that are listed in AD 2006-12-24, the same unsafe condition could exist or develop on the additional side links. Because there is no requirement to inspect or strip and reapply the Sermetel W coating on these additional part numbers in AD 2006-12-24, they might not have been inspected for cracks, which could lead to part failure. This proposed AD would add left-hand side link, P/N 9346M99P03, and right-hand side link, P/N 9346M99P04, to the applicability. We have also updated the applicability section to list the affected engine models in the same way they are listed on their Type Certificate Data Sheets.

Relevant Service Information

We have reviewed and approved the technical contents of GE Service Bulletins CF6-50 S/B 72-1255, Revision 1, dated June 17, 2009, and CF6-80A S/B 72-0797, Revision 1, dated June 17, 2009, that describe procedures for inspecting and stripping and reapplying the Sermetel W coating on the side links.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other products of this same type design. For that reason, we are proposing this AD, which would require inspecting and stripping and reapplying the Sermetel W coating on the side links at each exposure of the side link. The proposed AD would require that you do these actions using the service information described previously.

Costs of Compliance

We estimate that this proposed AD would affect 194 engines installed on airplanes of U.S. registry. We also estimate that it would take about 8 work-hours per engine to perform the proposed actions, and that the average labor rate is $85 per work-hour. We estimate the parts cost to be negligible because only a small percentage of parts will actually require replacement as a result of this proposed AD. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $131,920 per year.

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 proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 the proposed 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. Would 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 proposed AD. See the ADDRESSES section for a location to examine the regulatory evaluation.

Start List of Subjects

List of Subjects in 14 CFR Part 39

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The Proposed Amendment

Under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 14 CFR part 39 as follows:

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PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

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Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

2. The FAA amends § 39.13 by removing Amendment 39-14650 (71 FR 34807, June 16, 2006), and by adding a new airworthiness directive to read as follows:

General Electric Company: Docket No. FAA-2010-1151; Directorate Identifier 95-ANE-10-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by February 11, 2011.

Affected ADs

(b) This AD supersedes AD 2006-12-24, Amendment 39-14650.

Applicability

(c) This AD applies to General Electric (GE) CF6-45A, CF6-45A2, CF6-50A, CF6-50C, CF6-50CA, CF6-50C1, CF6-50C2, CF6-50C2B, CF6-50C2D, CF6-50E, CF6-50E1, CF6-50E2, CF6-50E2B, CF6-80A, CF6-80A1, CF6-80A2, and CF6-80A3 turbofan engines with left-hand side links part numbers (P/Ns) 9204M94P01, 9204M94P03, 9346M99P01, and 9346M99P03, and right-hand side links, P/Ns 9204M94P02, 9204M94P04, 9346M99P02, and 9346M99P04, installed on the five-link forward engine mount assembly (also known Start Printed Page 77572as Configuration 2). These engines are installed on, but not limited to, Boeing DC-10-30, DC-10-30F (KC-10A, KDC-10), 767, and 747 series airplanes and Airbus A300 and A310 series airplanes.

Unsafe Condition

(d) This AD results from a review of the inspection program, which revealed that GE had omitted two affected part numbers from the applicability. We are issuing this AD to prevent failure of the side links and possible engine separation from the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed at every exposure of the side link.

Inspecting and Stripping and Reapplying the Sermetel W Coating on the Side Links

(f) Inspect and strip and reapply the Sermetel W coating on each side link at every exposure of the side links. Use the following GE service bulletins (SBs):

(1) For CF6-45/-50 series engines, use paragraphs 3.A. through 3.E. of the Accomplishment Instructions of CF6-50 S/B 72-1255, Revision 1, dated June 17, 2009.

(2) For CF6-80A series engines, use paragraphs 3.A. through 3.E. of the Accomplishment Instructions of CF6-80A S/B 72-0797, Revision 1, dated June 17, 2009.

Definition of Exposure of Side Link

(g) A side link is exposed when one or more bolts that attach the side links to the fan frame-front high-pressure compressor case are removed, or when the bolt attaching the side link to the mount platform is removed.

Alternative Methods of Compliance

(h) 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

(i) Contact Tomasz Rakowski, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; telephone (781) 238-7735; fax (781) 238-7199, for more information about this AD.

(j) General Electric SBs CF6-50 S/B 72-1255, Revision 1, dated June 17, 2009, and CF6-80A S/B 72-0797, Revision 1, dated June 17, 2009, pertain to the subject of this AD. Contact General Electric Aviation Operations Center (AOC), telephone (877) 432-3272; fax (877) 432-3329; or go to: https://customer.geae.com, for a copy of this service information.

Start Signature

Issued in Burlington, Massachusetts, on November 17, 2010.

Peter A. White,

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

End Signature End Part End Supplemental Information

[FR Doc. 2010-31172 Filed 12-10-10; 8:45 am]

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