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Proposed Rule

Airworthiness Directives; General Electric Company CF34-1A, -3A, -3A1, -3A2, -3B, and -3B1 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:

Supplemental Notice of proposed rulemaking (NPRM); reopening of comment period.

SUMMARY:

This notice revises an earlier proposed airworthiness directive (AD), and supersedes an existing AD applicable to General Electric Company (GE) CF34-1A, -3A, -3A1, -3A2, -3B, and -3B1 turbofan engines. This proposed AD reopens the comment period, since we added additional requirements based on responses we received. This proposed AD would now require:

  • Inspecting certain fan disks for electrical arc-out indications,
  • Removing from service fan disks with electrical arc-out indications,
  • Performing tactile and enhanced visual (TEV) inspections, fluorescent penetrant inspections (FPI), and eddy current inspections (ECI) on certain disks that have already had a shop-level inspection, and
  • Repetitive FPI and ECI on certain fan disks.

This proposed AD results from an updated risk analysis by GE that shows we need to take corrective action that is more stringent. We are proposing this AD to prevent an uncontained failure of the fan disk, which could result in damage to the airplane.

DATES:

We must receive any comments on this proposed AD by June 16, 2009.

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.

Contact General Electric Company via Lockheed Martin Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 45215; telephone (513) 672-8400; fax (513) 672-8422, for the service information identified in this proposed AD.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Tara Chaidez, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: tara.chaidez@faa.gov; telephone (781) 238-7773; fax (781) 238-7199.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send us any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2007-27687; Directorate Identifier 2000-NE-42-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.

Discussion

We proposed to amend 14 CFR part 39 by superseding AD 2007-07-07R1, Amendment 39-15179 (72 FR 49183, August 28, 2007). That AD requires a onetime inspection of certain fan disks for electrical arc-out indications, replacing fan disks with electrical arc-out indications, and reducing the life limit of certain fan disks. That NPRM was prompted by us determining that we inadvertently left out an inspection requirement in Table C of AD 2007-07-07R1 to perform a shop inspection on disks that have greater than 6,000 flight hours and have already undergone a shop inspection. That condition, if not corrected, could result in an uncontained fan disk failure and airplane damage. On January 18, 2008, we published that proposal as an NPRM in the Federal Register (73 FR 3425). That NPRM would have required:

  • Replacing certain fan disks installed on regional jets within 15 days after the effective date of the proposed AD, and
  • On-wing and shop-level inspections of fan disks for electrical arc-out defects on fan disks installed on regional jets, and
  • Shop-level inspections of fan disks for electrical arc-out defects on fan disks installed on business jets.

Since we issued that NPRM, GE performed an updated risk analysis that shows we need to take corrective action that is more stringent than that proposed in the NPRM. We also propose to amend 14 CFR part 39 by superseding AD 2007-05-16, Amendment 39-14977 (72 FR 10054, March 7, 2007). That AD requires a onetime visual and tactile inspection of certain areas of certainP/N and SN fan disks for an arc-out defect, within 20 engine flight hours after the effective date of that AD. Since we issued that AD, GE has added those SN fan disks to the applicable service bulletins for the repetitive inspection requirements of this proposed AD.

Since these changes expand the scope of the originally proposed rule, we have determined that it is necessary to reopen the comment period to provide additional opportunity for public comment. This condition, if not corrected, could result in an uncontained failure of the fan disk and damage to the airplane.Start Printed Page 17800

Relevant Service Information

We have reviewed and approved the technical contents of GE Alert Service Bulletins (ASBs) No. CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008; CF34-BJ S/B 72-A0234, dated October 27, 2008; CF34-BJ S/B 72-A0235, dated October 27, 2008; CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008; CF34-AL S/B 72-A0252, dated October 27, 2008; and CF34-AL S/B 72-A0253, dated October 27, 2008. These ASBs list the affected fan disks by serial number, part number, and tier, and describe procedures for performing TEV inspections, FPI, and ECI for cracks and electrical arc-out defects.

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 initial and repetitive FPI, ECI, and TEV inspections. The proposed AD would require you to use the service information described previously to perform these actions.

Costs of Compliance

We estimate that this proposed AD would affect 1,531 engines installed on airplanes of U.S. registry. We also estimate that it would take about 2 work-hours per engine to perform the proposed on-wing inspection on 300 engines, and 4 work-hours per engine to perform the proposed shop inspection on 1,531 engines. The average labor rate is $80 per work-hour. There are no required parts. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $537,920.

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. You may get a copy of this summary at the address listed under ADDRESSES.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

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:

Start Part

PART 39—AIRWORTHINESS DIRECTIVES

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

Start Authority

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

End Authority
[Amended]

2. The FAA amends § 39.13 by removing Amendment 39-14977 (72 FR 10054, March 7, 2007) and Amendment 39-15179 (72 FR 49183, August 28, 2007), and by adding a new airworthiness directive to read as follows:

General Electric Company: Docket No. FAA-2007-27687; Directorate Identifier 2000-NE-42-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by June 16, 2009.

(b) This AD supersedes AD 2007-05-16, Amendment 39-14977 and AD 2007-07-07R1, Amendment 39-15179.

Applicability

(c) This AD applies to General Electric Company (GE) CF34-1A, -3A, -3A1, -3A2, -3B, and -3B1 turbofan engines, with fan disks part numbers (P/Ns) 5921T18G01, 5921T18G09, 5921T18G10, 5921T54G01, 5922T01G02, 5922T01G04, 5922T01G05, 6020T62G04, 6020T62G05, 6078T00G01, 6078T57G01, 6078T57G02, 6078T57G03, 6078T57G04, 6078T57G05, and 6078T57G06 installed. These engines are installed on, but not limited to, Bombardier Canadair airplane models CL-600-2A12, -2B16, and -2B19.

Unsafe Condition

(d) This AD results from an updated risk analysis by GE that shows we need to take corrective action that is more stringent. We are issuing this AD to prevent an uncontained failure of the fan disk, which could result in damage to the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.

Removing Certain Fan Disks from Service

(f) For fan disks listed by P/N and serial number (SN) in Table 2 of GE Alert Service Bulletin (ASB) CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008; or in Table 2 of GE ASB CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008 that have 8,000 CSN or more on the effective date of this AD, remove fan disks from service within 15 days after the effective date of this AD.

(g) For fan disks listed by P/N and serial number (SN) in Table 2 of GE Alert Service Bulletin (ASB) CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008; or in Table 2 of GE ASB CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008, that have fewer than 8,000 CSN on the effective date of this AD, remove fan disks from service before accumulating 8,000 CSN.

Inspections of Tier 1 Fan Disks

(h) For CF34-3A1 engines with fan drive shaft, P/N 6036T78P02, and airworthiness limitation section life limit of 22,000 CSN, and CF34-3B1 turbofan engines with Tier 1 fan disks listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008, do the following:

Tactile and Enhanced Visual (TEV) Inspections, Fluorescent Penetrant Inspections (FPI), and Eddy Current Inspections (ECI)

(1) For Tier 1 fan disks not already inspected using GE ASB No. CF34-AL S/B 72-A0233, Revision 03, dated June 27, 2007, or earlier issue, do the following:

(i) Perform a TEV inspection, an FPI, and an ECI on the Tier 1 fan disks within 650 cycles-in-service (CIS) after the effective date of this AD. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0233, Revision 04, dated Start Printed Page 17801October 27, 2008, to perform the TEV inspection, FPI, and ECI.

(ii) Thereafter, perform repetitive ECI on the Tier 1 fan disks within intervals of 3,000 cycles-since-last inspection (CSLI). Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0252, dated October 27, 2008, to perform the repetitive ECI.

(2) For Tier 1 fan disks, listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008; already inspected using GE ASB No. CF34-AL S/B 72-A0233, Revision 03, dated June 27, 2007, or earlier issue, do the following:

(i) For Tier 1 fan disks with 2,500 or more CSLI on the effective date of this AD, perform an ECI on the Tier 1 fan disks within 500 CIS after the effective date of this AD. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0252, dated October 27, 2008, to perform the ECI.

(ii) For Tier 1 fan disks with fewer than 2,500 CSLI on the effective date of this AD, perform an ECI on the Tier 1 fan disks within 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0252, dated October 27, 2008, to perform the ECI.

(iii) Thereafter, perform repetitive ECI on the Tier 1 fan disks within intervals of 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0252, dated October 27, 2008, to perform the repetitive ECI.

Inspections of Tier 2 Fan Disks

(i) For CF34-3A1 engines with fan drive shaft, P/N 6036T78P02, and airworthiness limitation section life limit of 22,000 CSN, and CF34-3B1 turbofan engines with Tier 2 fan disks listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008, do the following:

TEV Inspections, FPI, and ECI

(1) For Tier 2 fan disks not already inspected using GE ASB No. CF34-AL S/B 72-A0233, Revision 03, dated June 27, 2007, or earlier issue, do the following:

(i) Perform a TEV inspection, an FPI, and an ECI on the Tier 2 fan disks within 2,000 CIS after the effective date of this AD, or within 5,000 CIS after September 12, 2007, or by March 19, 2012, whichever occurs first. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008, to perform the TEV inspection, FPI, and ECI.

(ii) Thereafter, perform repetitive eddy current inspections on the Tier 2 fan disks within intervals of 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0252, dated October 27, 2008, to perform the repetitive ECI.

(2) For Tier 2 fan disks, listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008; already inspected using GE ASB No. CF34-AL S/B 72-A0233, Revision 03, dated June 27, 2007, or earlier issue, do the following:

(i) For Tier 2 fan disks with 2,500 or more CSLI on the effective date of this AD, perform an ECI on the Tier 2 fan disks within 500 CIS after the effective date of this AD. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0252, dated October 27, 2008, to perform the ECI.

(ii) For Tier 2 fan disks with fewer than 2,500 CSLI on the effective date of this AD, perform an ECI on the Tier 2 fan disks within 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0252, dated October 27, 2008, to perform the ECI.

(iii) Thereafter, perform repetitive ECI on the Tier 2 fan disks within intervals of 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0252, dated October 27, 2008, to perform the repetitive ECI.

Inspections of Tier 3 Fan Disks

(j) For CF34-3A1 engines with fan drive shaft, P/N 6036T78P02, and airworthiness limitation section life limit of 22,000 CSN, and CF34-3B1 turbofan engines with Tier 3 fan disks, listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008, do the following:

TEV Inspections, FPI, and ECI

(1) For Tier 3 fan disks not already inspected using GE ASB No. CF34-AL S/B 72-A0233, Revision 03, dated June 27, 2007, or earlier issue, perform a TEV inspection, an FPI, and an ECI on the Tier 3 fan disks within 5,000 CIS after September 12, 2007, or by March 19, 2012, whichever is earlier. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0253, Revision 04, dated October 27, 2008, to perform the TEV inspection, FPI, and ECI.

(2) For Tier 3 fan disks, listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008; already inspected using GE ASB No. CF34-AL S/B 72-A0233, Revision 03, dated June 27, 2007, or earlier issue, perform a TEV inspection and an ECI on the Tier 3 fan disks at the next shop visit. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0253, dated October 27, 2008, to perform the TEV inspection and ECI.

(3) Repetitive ECI on the Tier 3 fan disks are not required.

Inspections of Tier 1 Fan Disks

(k) For CF34-1A turbofan engines with fan drive shaft, P/N 6036T78P02, and airworthiness limitation section life limit of 15,000 CSN, CF34-3A, CF34-3A2, and CF34-3B turbofan engines with Tier 1 fan disks listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008, do the following:

TEV Inspections, FPI, and ECI

(1) For Tier 1 fan disks not already inspected using GE ASB No. CF34-BJ S/B 72-A0212, Revision 03, dated June 27, 2007, or earlier issue:

(i) Perform a TEV inspection, FPI, and ECI on the Tier 1 fan disks within 350 CIS after the effective date of this AD. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008, to perform the TEV inspection.

(ii) Thereafter, perform repetitive ECI on the Tier 1 fan disks within intervals of 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0235, dated October 27, 2008, to perform the repetitive ECI.

(2) For Tier 1 fan disks, listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008; already inspected using GE ASB No. CF34-BJ S/B 72-A0212, Revision 03, dated June 27, 2007, or earlier issue, do the following:

(i) For Tier 1 fan disks with 2,500 or more CSLI on the effective date of this AD, perform an ECI on the Tier 1 fan disks within 500 CIS after the effective date of this AD. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0235, dated October 27, 2008, to perform the ECI.

(ii) For Tier 1 fan disks with fewer than 2,500 CSLI on the effective date of this AD, perform an ECI on the Tier 1 fan disks within 3,000 CSLI after the effective date of this AD. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0235, dated October 27, 2008, to perform the ECI.

(iii) Thereafter, perform repetitive ECI on the Tier 1 fan disks within intervals of 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0235, dated October 27, 2008, to perform the repetitive ECI.

Inspections of Tier 2 Fan Disks

(l) For CF34-1A turbofan engines with fan drive shaft, P/N 6036T78P02, and airworthiness limitation section life limit of 15,000 CSN, CF34-3A, CF34-3A2, and CF34-3B turbofan engines with Tier 2 fan disks listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-AL S/B 72-A0212, Revision 04, dated October 27, 2008, do the following:

TEV Inspections, FPI, and ECI

(1) For Tier 2 fan disks not already inspected using GE ASB No. CF34-AL S/B 72-A0212, Revision 03, dated June 27, 2007, or earlier issue, do the following:

(i) Perform a TEV inspection, FPI, and ECI on the Tier 2 fan disks within 2,000 CIS after the effective date of this AD, or within 3,500 CIS after September 12, 2007, or by March 19, 2012, whichever occurs first. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008, to perform the TEV inspection, FPI, and ECI.

(ii) Thereafter, perform repetitive ECI on the Tier 2 fan disks within intervals of 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0235, dated October 27, 2008, to perform the repetitive ECI.

(2) For Tier 2 fan disks, listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008; already inspected using GE ASB Start Printed Page 17802No. CF34-BJ S/B 72-A0212, Revision 03, dated June 27, 2007, or earlier issue, do the following:

(i) For Tier 2 fan disks with 2,500 or more CSLI on the effective date of this AD, perform an ECI on the Tier 2 fan disks within 500 CIS after the effective date of this AD. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0235, dated October 27, 2008, to perform the ECI.

(ii) For Tier 2 fan disks with fewer than 2,500 CSLI on the effective date of this AD, perform an ECI on the Tier 2 fan disks within 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0235, dated October 27, 2008, to perform the ECI.

(iii) Thereafter, perform repetitive ECI on the Tier 2 fan disks within intervals of 3,000 CSLI. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0235, dated October 27, 2008, to perform the repetitive ECI.

Inspections of Tier 3 Fan Disks

(m) For CF34-1A turbofan engines with fan drive shaft, P/N 6036T78P02, and airworthiness limitation section life limit of 15,000 CSN, CF34-3A, CF34-3A2, and CF34-3B turbofan engines with Tier 3 fan disks listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008, do the following:

TEV Inspections, FPI, and ECI

(1) For Tier 3 fan disks not already inspected using GE ASB No. CF34-AL S/B 72-A0212, Revision 03, dated June 27, 2007, or earlier issue, perform a TEV inspection, FPI, and ECI on the Tier 3 fan disks within 3,500 CIS after September 12, 2007, or by March 19, 2012, whichever is earlier. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-AL S/B 72-A0234, dated October 27, 2008, to perform the TEV inspection, FPI, and ECI.

(2) For Tier 3 fan disks, listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008; already inspected using GE ASB No. CF34-BJ S/B 72-A0212, Revision 03, dated June 27, 2007, or earlier issue, perform a TEV inspection and an ECI on the Tier 3 fan disks within 3,500 CSLI, but no later than March 19, 2012. Use paragraph 3.A of the Accomplishment Instructions of GE ASB CF34-BJ S/B 72-A0234, dated October 27, 2008, to perform the TEV inspection and ECI.

(3) Repetitive ECI on the Tier 3 fan disks are not required.

Alternative Methods of Compliance

(n) 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.

Mandatory Terminating Action

(o) Remove from service, Tier 1 and Tier 2 fan disks listed by P/N, SN, and Tier in Table 1 of GE ASB No. CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008; or CF34-BJ S/B 72-0212, Revision 04, dated October 27, 2008, before they exceed their limited life cycles or September 30, 2018, whichever occurs first.

Related Information

(p) Contact Tara Chaidez, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: tara.chaidez@faa.gov; telephone (781) 238-7773; fax (781) 238-7199, for more information about this AD.

(q) The following GE Alert Service Bulletins pertain to the subject of this AD:

  • CF34-AL S/B 72-A0233, Revision 04, dated October 27, 2008,
  • CF34-AL S/B 72-A0252, dated October 27, 2008,
  • CF34-AL S/B 72-A0253, dated October 27, 2008,
  • CF34-BJ S/B 72-A0212, Revision 04, dated October 27, 2008,
  • CF34-BJ S/B 72-A0234, dated October 27, 2008, and
  • CF34-BJ S/B 72-A0235, dated October 27, 2008.

Contact General Electric Company via Lockheed Martin Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 45215; telephone (513) 672-8400; fax (513) 672-8422, for a copy of this service information.

Start Signature

Issued in Burlington, Massachusetts, on April 9, 2009.

Peter A. White,

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

End Signature End Part End Supplemental Information

[FR Doc. E9-8787 Filed 4-16-09; 8:45 am]

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