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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), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) for General Electric Company (GE) CF34-1A, -3A, -3A1, -3A2, -3B, and -3B1 turbofan engines. That AD currently 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. This proposed AD would require the same reduced life limit of certain fan disks, on-wing inspection of certain fan disks installed on regional jets, and would add a requirement to perform an inspection on certain business jet applications that have already had a shop-level inspection. This proposed AD results from us determining that we inadvertently left out an inspection requirement. We are proposing this AD to prevent uncontained fan disk failure and airplane damage.

DATES:

We must receive any comments on this proposed AD by March 18, 2008.

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 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 Start Printed Page 3426received, 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

The FAA proposes 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 AD was the result of GE revising their service information and a comment from an operator asking us to clarify Table C of this AD. That condition, if not corrected, could result in an uncontained fan disk failure and airplane damage.

Actions Since AD 2007-07-07R1 Was Issued

Since we issued that AD, we determined that we inadvertently left out an inspection requirement in Table C of that AD to perform a shop inspection on disks that have greater than 6,000 flight hours and have already undergone a shop inspection.

Relevant Service Information

We have reviewed and approved the technical contents of GE ASB No. CF34-BJ S/B 72-A0212, Revision 3, dated June 27, 2007, ASB No. CF34-AL S/B 72-A0233, Revision 3, dated June 27, 2007, and ASB No. CF34-AL S/B 72-A0231, Revision 1, dated June 27, 2007. All three ASBs list the affected fan disks by serial number and part number. The first two ASBs describe procedures for performing fluorescent penetrant inspection (FPI), a Tactile and Enhanced Visual (TEV) inspection, and eddy current inspection (ECI) for cracks and electrical arc-out defects. The third ASB describes procedures for performing an on-wing TEV inspection of fan disks for electrical arc-out defects.

FAA's Determination and Requirements of This AD

The unsafe condition described previously is likely to exist or develop on other GE CF34-1A, -3A, -3A1, -3A2, -3B, and -3B1 turbofan engines of the same type design. For that reason, we are proposing this AD to prevent an uncontained fan disk failure and airplane damage. This proposed AD would require:

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

You must use the service information described previously to perform the actions required by this AD.

Costs of Compliance

We estimate that this proposed AD would affect 1,727 engines installed on airplanes of U.S. registry. We also estimate that it would take about 6.0 work-hours per engine to perform the proposed actions, and that 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 $828,960.

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

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 39-15179 (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 March 18, 2008.

Affected ADs

(b) This AD supersedes 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 us determining that we inadvertently left out an inspection requirement. We are issuing this AD to prevent uncontained fan disk failure and airplane damage.

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. Start Printed Page 3427

Removal of Certain Fan Disks From Service

(f) For fan disks listed by P/N and serial number (SN) in the following Table A that have fewer than 8,000 cycles-since-new (CSN) on the effective date of this AD, replace fan disks before accumulating 8,000 CSN:

Table A.—Fan Disks That Require Removal Based on Blended Callouts

Disk part No.Disk serial No.
6078T57G02GAT6306N
6078T00G01GAT3860G
6078T57G02GAT1924L
5922T01G04GAT9599G
6078T57G04GEE05831
6078T57G04GEE06612
6078T57G04GEE06618
6078T57G04GEE06974
6078T57G04GEE06980
6078T57G05GEE143FY
6078T57G05GEE1453G
6078T57G05GEE14452
6078T57G05GEE145NA
6078T57G04GEE08086
6078T57G04GEE09287
6078T57G04GEE09337
6078T57G05GEE12720
6078T57G05GEE14214
6078T57G05GEE142YT
6078T57G05GEE146GT

(g) For fan disks listed in Table A of this AD that have 8,000 CSN or more on the effective date of this AD, replace the disk within 15 days after the effective date of this AD.

Inspections of Fan Disks Installed in Regional Jet Airplanes

(h) For CF34-3A1 and CF34-3B1 turbofan engines installed on Bombardier Canadair CL600-2B19 Regional Jet airplanes:

On-Wing Tactile and Enhanced Visual (TEV) Inspection

(1) Perform an on-wing TEV inspection on the fan disks listed by P/N and SN in Table 1 of GE ASB No. CF34-AL S/B 72-A0231, Revision 1, dated June 27, 2007, using the compliance times specified in the following Table B:

Table B.—Regional Jet On-Wing Fan Disk Inspection Compliance Times

For fan disks:Inspect:
(i) That have not had a shop-level inspectionWithin 500 flight hours after September 12, 2007.
(ii) That are marked with an asterisk in Table 1 of GE ASB No. CF34-AL S/B 72-A0231, Revision 1, dated June 27, 2007Within 500 flight hours after September 12, 2007.

(2) Use paragraphs 3.A. through 3.A.(13) of the Accomplishment Instructions of GE ASB No. CF34-AL S/B 72-A0231, Revision 1, dated June 27, 2007, to do the inspection.

Shop-Level Inspection

(3) Within 5,000 flight hours or by September 12, 2012, whichever occurs first, fluorescent-penetrant inspect (FPI), TEV inspect, and eddy current inspect (ECI) at shop-level for cracks and electrical arc-out defects on the fan disks listed by P/N and SN in Table 1 of GE ASB No. CF34-AL S/B 72-A0233, Revision 3, dated June 27, 2007.

(4) Use paragraphs 3.A.(1) through 3.A.(6) of the Accomplishment Instructions of GE ASB No. CF34-AL S/B 72-A0233, Revision 3, dated June 27, 2007, to do the inspections.

Shop-Level Inspection Exemption

(5) Fan disks that meet the following criteria are exempt from the shop-level inspection:

(i) Fan disks inspected before the effective date of this AD per GE Engine Manual No. SEI-756, Section 72-21-00 (FAN ROTOR ASSEMBLY INSPECTION); and

(ii) That have accumulated no more than 100 cycles since that inspection; and

(iii) That pass the on-wing TEV inspection in paragraph (h)(2) of this AD.

Inspection of Fan Disks Installed in Business Jet Airplanes

(i) For CF34-1A, -3A, -3A1, -3A2, and -3B turbofan engines installed on Bombardier Canadair Models CL-600-2A12 (CL-601), CL-600-2B16 (CL-601-3A), (CL-601-3R), and (CL-604) Business Jet airplanes:

(1) FPI, TEV inspect, and ECI for cracks and electrical arc-out defects at shop-level on the fan disks listed by P/N and SN in Table 1 of GE ASB No. CF34-BJ S/B 72-A0212, Revision 3, dated June 27, 2007, using the compliance times specified in the following Table C:

Table C.—Business Jet Shop-level Fan Disk Inspection Compliance Times

For fan disks:Inspect:
(i) That have not had a shop-level inspection and have more than 5,500 flight hours on September 12, 2007Within 500 flight hours after September 12, 2007.
(ii) That have not had a shop-level inspection and have 5,500 or fewer flight hours on the effective date of this ADWithin accumulating a total of 6,000 fan disk operating hours-since-new or by September 12, 2012, whichever occurs first.
(iii) That have had a shop-level inspectionWithin accumulating an additional 6,000 fan disk operating hours-since-shop-level inspection, or by September 12, 2012, whichever occurs first.

(2) Use paragraphs 3.A. through 3.A.(10) of the Accomplishment Instructions of GE ASB No. CF34-BJ S/B 72-A0212, Revision 3, dated June 27, 2007, to do the inspections.

Reporting Requirements

(j) Under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements contained in this AD, and has assigned OMB Control Number 2120-0056.

(1) Report the results of the on-wing inspections performed in paragraph (h)(2) of this AD by following the instructions in paragraph 3.A.(14) of the Accomplishment Instructions of GE ASB No. CF34-AL S/B 72-A0231, Revision 1, dated June 27, 2007.

(2) Report the results of the shop-level inspections performed in paragraph (h)(4) of this AD by following the instructions in paragraph 3.A.(3)(b)11 of the Accomplishment Instructions of GE ASB No. CF34-AL S/B 72-A0233, Revision 3, dated June 27, 2007.

(3) Report the results of the shop-level inspections performed in paragraph (i)(2) of this AD by following the instructions in paragraph 3.A.(3)(b)11 of the Accomplishment Instructions of GE ASB No. CF34-AL S/B 72-A0212, Revision 3, dated June 27, 2007.

Previous Credit

(k) We are allowing previous credit for:

(1) Fan disks previously shop-level inspected before the effective date of this AD using GE ASB No. CF34-AL S/B 72-A0233, Start Printed Page 3428dated March 7, 2007, Revision 1, dated March 16, 2007, or Revision 2, dated March 22, 2007; and GE ASB No. CF34-BJ S/B 72-A0212, dated March 7, 2007, Revision 1, dated March 16, 2007, or Revision 2, dated March 22, 2007.

(2) Fan disks previously on-wing TEV inspected before the effective date of this AD using GE ASB No. CF34-AL S/B 72-A0231, dated March 7, 2007.

Alternative Methods of Compliance

(l) 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

(m) Emergency AD 2007-04-51 and AD 2007-05-16 also pertain to the subject of this AD.

(n) GE Alert Service Bulletins ASB No. CF34-BJ S/B 72-A0212, Revision 3, dated June 27, 2007; ASB No. CF34-AL S/B 72-A0233, Revision 3, dated June 27, 2007; and ASB No. CF34-AL S/B 72-A0231, Revision 1, dated June 27, 2007; pertain to the subject of this AD.

(o) 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.

Start Signature

Issued in Burlington, Massachusetts, on January 10, 2008.

Peter A. White,

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

End Signature End Part End Supplemental Information

[FR Doc. E8-821 Filed 1-17-08; 8:45 am]

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