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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

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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 Company (GE) CF6-45/-50 series turbofan engines. That AD currently requires an initial and repetitive on-wing visual inspection of the side links of the five-link forward mount assembly for cracks, and replacement of the side links and pylon attachment bolts and inspection of the fail-safe bolt and platform lug if the side links are cracked. That AD also requires a shop-level refurbishment of the side links as a terminating action to the on-wing inspection program. This proposed AD would require inspecting and refurbishing the side link at every exposure of the side link. This proposed AD would also require the same actions on certain part number side links installed on CF6-80A turbofan engines. This proposed AD results from a report of a cracked side link. 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 10, 2006.

ADDRESSES:

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

  • By mail: Federal Aviation Administration (FAA), New England Region, Office of the Regional Counsel, Attention: Rules Docket No. 95-ANE-10-AD, 12 New England Executive Park, Burlington, MA 01803-5299.
  • By fax: (781) 238-7055.
  • By e-mail: 9-ane-adcomment@faa.gov.

You can get the service information identified in this proposed AD from General Electric Aircraft Engines, CF6 Distribution Clerk, Room 132, 111 Merchant Street, Cincinnati, OH 45246.

You may examine the AD docket at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA.

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FOR FURTHER INFORMATION CONTACT:

Karen Curtis, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (617) 238-7192; fax (617) 238-7199.

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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 “AD Docket No. 95-ANE-10-AD” in the subject line of your comments. If you want us to acknowledge receipt of your mailed comments, send us a self-addressed, stamped postcard with the docket number written on it; we will date-stamp your postcard and mail it back to you. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. If a person contacts us verbally, and that contact relates to a substantive part of this proposed AD, we will summarize the contact and place the summary in the docket. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

Examining the AD Docket

You may examine the AD Docket (including any comments and service information), by appointment, between 8:00 a.m. and 4:30 p.m., Monday through Friday, except Federal holidays. See ADDRESSES for the location.

Discussion

On August 15, 1995, the FAA issued AD 95-17-15, Amendment 39-9346 (60 FR 46758, September 8, 1995). That AD requires an initial and repetitive on-wing visual inspection of the side links of the five-link forward mount assembly for cracks, and replacement of the side links and pylon attachment bolts and inspection of the fail-safe bolt and platform lug, if side links are found cracked. That AD also requires a shop-level refurbishment of the side links as a terminating action to the on-wing inspection program. That AD was the result of six reports of cracked side links detected during routine engine shop visits. That condition, if not corrected, could result in failure of the side links and possible engine separation from the airplane.

Actions Since We Issued AD 95-17-15

Since we issued AD 95-17-15, a routine inspection at a shop visit found a cracked side link. A review of the records of the cracked part showed that it was previously refurbished and was in compliance with AD 95-17-15. That AD required initial and repetitive on-wing inspection of the CF6-45/50 side links until refurbished using GE Service Bulletin 72-1092, dated November 18, 1994. Refurbishment includes reapplication of the protective Sermetel W coating. That AD didn't specify any repetitive refurbishment. That AD also didn't include initial or repetitive inspections of the side links installed on CF6-80A series engines, even though some P/Ns are common to both engine series. The manufacturer previously issued several documents including Commercial Engine Services Memoranda (CESM) 201, All Operator Wires, and service bulletins recommending inspecting and refurbishing the side links per the engine manual at each piece part exposure for both the CF6-45/-50 and the CF6-80A series engines. The manufacturer recently issued temporary revisions to Chapter 5 of the Airworthiness Limitations sections of the CF6-45/-50 and CF6-80A engine manuals to require inspecting and refurbishing 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.

Relevant Service Information

We have reviewed and approved the technical contents of GE Aircraft Start Printed Page 73392Engines (GEAE) Service Bulletins CF6-50 S/B 72-1255, dated January 26, 2005, and CF6-80A S/B 72-0797, dated January 26, 2005, that describe procedures for inspecting and refurbishing 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. We are proposing this AD, which would require inspecting and refurbishing 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 195 engines installed on U.S. registered airplanes per year. We also estimate that it would take 8.0 work hours per engine to perform the proposed actions, and that the average labor rate is $65 per work hour. This AD does not require parts. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $101,400 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 regulation:

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 summary of the costs to comply with this proposal and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 95-ANE-10-AD” in your request.

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List of Subjects in 14 CFR Part 39

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The Proposed Amendment

Accordingly, 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.

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[Amended]

2. The FAA amends § 39.13 by removing Amendment 39-9346 (60 FR 46758, September 8, 1995) and by adding a new airworthiness directive to read as follows:

General Electric Company: Docket No. 95-ANE-10-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by February 10, 2006.

Affected ADs

(b) This AD supersedes AD 95-17-15, Amendment 39-9346.

Applicability

(c) This AD applies to General Electric (GE) CF6-45/-50 and CF6-80A turbofan engines with left-hand side links part numbers (P/Ns) 9204M94P01, 9204M94P03, and 9346M99P01, and right-hand side links, P/Ns 9204M94P02, 9204M94P04, and 9346M99P02, installed on the five-link forward engine mount assembly (also known as Configuration 2). These engines are installed on, but not limited to, Boeing DC10-15, DC10-30, 767, and 747 series airplanes and Airbus Industrie A300 and A310 series airplanes.

Unsafe Condition

(d) This AD results from a report of a cracked side link. 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 Refurbishing the Side Links

(f) Inspect and refurbish each side link at every exposure of the side links. Use the following GE Aircraft Engines (GEAE) service bulletins (SBs):

(1) For CF6-45/-50 series engines, use 3.A. through 3.E. of the Accomplishment Instructions of GEAE SB CF6-50 S/B 72-1255, dated January 26, 2005.

(2) For CF6-80A series engines, use 3.A. through 3.E. of the Accomplishment Instructions of GEAE SB CF6-80A S/B 72-0797, dated January 26, 2005.

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) None.

Start Signature

Issued in Burlington, Massachusetts, on December 1, 2005.

Peter A. White,

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

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[FR Doc. 05-23898 Filed 12-9-05; 8:45 am]

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