E7-17680. Airworthiness Directives; General Electric Company CF34-8C1/-8C5/-8C5B1/-8E5/-8E5A1, and CF34-10E Series Turbofan Engines

AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for General Electric Company (GE) CF34-8C1/-8C5/-8C5B1/-8E5/-8E5A1, and CF34-10E series turbofan engines with certain part number (P/N) and serial number (SN) fuel metering units (FMU) installed. This proposed AD would require a onetime test of the FMU for a miswired (reversed polarity) condition of the input wires to the overspeed solenoid. This proposed AD results from the discovery of miswired FMU overspeed solenoids in the field. We are proposing this AD to prevent the engine from failing to shutdown as commanded during an overspeed, leading to uncontained engine failure.

DATES:

We must receive any comments on this proposed AD by November 6, 2007.

ADDRESSES:

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

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Fax: [phone].

You can get the service information identified in this proposed AD from General Electric Company via Lockheed Martin Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 45215; telephone [phone]; fax [phone].

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: [e-mail]; telephone [phone]; fax [phone].

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-2007-29001; Directorate Identifier 2007-NE-36-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://dms.dot.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 DOT 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) or you may visit http://dms.dot.gov.

Examining the AD Docket

You may examine the AD docket on the Internet at http://dms.dot.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 [phone]) is the same as the Mail address provided in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

Discussion

Woodward Governor Company has discovered in the field a miswired (reversed polarity) condition of the input wires to the overspeed solenoid, on some FMUs. Investigation of FMU manufacturing records shows that there is a possibility that a population of FMUs might be miswired. If the solenoid is miswired, the engine will fail to shut down as commanded. This condition, if not corrected, could result in failure of the engine to shutdown as commanded during an overspeed, leading to uncontained engine failure.

Relevant Service Information

We have reviewed and approved the technical contents of GE Service Bulletin (SB) No. CF34-8C-AL S/B 73-0030, Revision 1, dated July 19, 2007, SB No. CF34-8E-AL S/B 73-0015, Revision 1, dated July 19, 2007, and SB No. CF34-10E S/B 72-0067, Revision 1, dated July 26, 2007 that describe procedures for performing a onetime test of suspect FMUs for a miswired (reversed polarity) condition of the input wires to the overspeed solenoid.

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 a onetime test of suspect FMUs for a miswired (reversed polarity) condition of the input wires to the overspeed solenoid. 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 1,055 engines installed on airplanes of U.S. registry. We also estimate that it would take about 0.25 work-hour per engine to perform the proposed actions, and that the average labor rate is $80 per work-hour. We estimate that about 2 percent of the inspected solenoids are defective, and it will cost about $5,000 to replace each FMU. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $180,000. Our cost estimate is exclusive of possible warranty coverage.

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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

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:

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:

General Electric Company: Docket No. FAA-2007-29001; Directorate Identifier 2007-NE-36-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by November 6, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to:

(1) General Electric Company (GE) CF34-8C1/-8C5/-8C5B1/-8E5/-8E5A1 turbofan engines, with GE fuel metering unit (FMU) part number (P/N) 4120T01P02, serial numbers (SNs) WYG94939 through WYGB4222, and Woodward Governor FMU Vendor Identification Number (VIN) 8061-926, SNs 11954378 through 15140071.

(2) GE CF34-10E series turbofan engines, with GE FMU P/N 2043M10P05, SNs WYGA3251 through WYGB4085, and Woodward Governor FMU VIN 8063-884, SNs 13335695 through 15028283.

(3) CF34-8C1/-8C5/-8C5B1 turbofan engines are installed on, but not limited to, Bombardier Inc. Model CL-600-2C10 (CRJ-700 & -701), and CL-600-2D24/-2D15 (CRJ-900) airplanes.

(4) CF34-8E5/-8E5A1 turbofan engines are installed on, but not limited to, Embraer ERJ 170-100/-200 series airplanes.

(5) CF34-10E series turbofan engines are installed on, but not limited to, Embraer ERJ 190-100/-200 series airplanes.

Unsafe Condition

(d) This AD results from the discovery of miswired FMU overspeed solenoids in the field. We are issuing this AD to prevent failure of the engine to shutdown as commanded during an overspeed, leading to uncontained engine failure.

Compliance

(e) You are responsible for having the actions required by this AD performed within 2,200 flight hours after the effective date of this AD, but not to exceed 24 months after the effective date of this AD, unless the actions have already been done.

Onetime Test of the FMU

(f) Perform a onetime test of the FMU for a miswired (reversed polarity) condition of the input wires to the overspeed solenoid.

(g) Use paragraph 3A of the Accomplishment Instructions of GE Service Bulletin (SB) No. CF34-8C-AL S/B 73-0030, Revision 1, dated July 19, 2007, SB No. CF34-8E-AL S/B 73-0015, Revision 1, dated July 19, 2007, or SB No. CF34-10E S/B 72-0067, Revision 1, dated July 26, 2007, as applicable, to do the test.

(h) If the FMU fails the test, remove the FMU.

Previous Credit

(i) If you performed the actions specified in paragraphs (f) through (h) of this AD, using the inspection procedures in GE SB No. CF34-8C-AL S/B 73-0030, dated May 25, 2007, SB No. CF34-8E-AL S/B 73-0015, dated June 1, 2007, or SB No. CF34-10E S/B 72-0067, dated June 7, 2007, before the effective date of this AD, you have satisfied the compliance requirements of this AD.

Reporting Requirements

(j) At the applicable time specified in paragraph (j)(4) or (j)(5) of this AD:

(1) Submit a report of all findings (both positive and negative) of the testing required by paragraph (f) of this AD to Customer Support Manager, Woodward Governor Company, e-mail: [e-mail]; telephone [phone].

(2) The report must include date of inspection, serial number of FMU, and results of the inspection.

(3) Under the provisions of the Paperwork Reduction Act (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.

(4) If the inspection is done after the effective date of this AD, submit the report within 10 days after the inspection.

(5) If the inspection was done before the effective date of this AD, submit the report within 10 days after the effective date of this AD.

Alternative Methods of Compliance

(k) 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

(l) None.

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

Issued in Burlington, Massachusetts, on August 28, 2007.

Peter A. White,

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