E7-10746. Airworthiness Directives; General Electric Company CF34-10E Series Turbofan Engines

AGENCY:

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

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for General Electric Company (GE) CF34-10E series turbofan engines. This AD requires revising the combustor case published life limit and removing combustor cases from service before reaching a reduced life limit. This AD results from GE's evaluation of the effects to the combustor case due to installing version 5.10 software in the full-authority digital electronic control (FADEC), and revising the combustor case published life limit. We are issuing this AD to prevent uncontained combustor case failure resulting in an in-flight engine shutdown and possible damage to the airplane.

DATES:

This AD becomes effective July 10, 2007.

ADDRESSES:

You may examine the AD docket on the Internet at http://dms.dot.gov or in Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Tara Chaidez, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [e-mail]; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

The FAA proposed to amend 14 CFR part 39 with a proposed AD. The proposed AD applies to GE CF34-10E series turbofan engines. We published the proposed AD in the Federal Register on January 17, 2007 (72 FR 1946). That action proposed to require revising the combustor case published life limit and removing combustor cases from service before reaching a reduced life limit.

Examining the AD Docket

You may examine the docket that contains the AD, any comments received, and any final disposition in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone [phone]) is located on the plaza level of the Department of Transportation Nassif Building at the street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the DMS receives them.

Comments

We provided the public the opportunity to participate in the development of this AD. We received no comments on the proposal or on the determination of the cost to the public.

Elimination of Paragraph (g)

After we issued the proposed AD, our review indicated that we should simplify the compliance by eliminating paragraph (g). That paragraph is redundant to paragraph (f), and would only add an additional requirement for the operators to show compliance after removal of every affected part. We eliminated the proposed AD paragraph (g), and re-codified the paragraphs, in this AD.

Conclusion

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

We estimate that this AD will affect 42 CF34-10E series turbofan engines installed on airplanes of U.S. registry. This combustor case removal does not impose any additional labor costs if performed at the time of scheduled engine overhaul. The financial burden to the operators (prorate) is about $140,080 per engine due to the reduction in the life limit. Based on these figures, and on the prorating for the usage of the combustor cases, we estimate the cost of the AD on U.S. operators to be $5,886,720.

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 AD will not have federalism implications under Executive Order 13132. This AD will 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 this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866;

(2) Is not a “significant rule” under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

(3) Will 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 AD and placed it in the AD Docket. 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

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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:

2007-12-09 General Electric Company: Amendment 39-15087. Docket No. FAA-2006-26585; Directorate Identifier 2006-NE-44-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective July 10, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to General Electric Company (GE) CF34-10E2A1, CF34-10E5, CF34-10E5A1, CF34-10E6, CF34-10E6A1, and CF34-10E7 turbofan engines. These engines are installed on, but not limited to, Embraer ERJ-190 and -195 airplanes.

Unsafe Condition

(d) This AD results from GE's evaluation of the effects to the combustor case due to installing version 5.10 software in the full-authority digital electronic control (FADEC), and revising the combustor case published life limit. We are issuing this AD to prevent uncontained combustor case failure resulting in an in-flight engine shutdown and possible damage to the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within 30 days after the effective date of this AD, unless the actions have already been done.

(f) Revise the published life limit in the Airworthiness Limitations Section of the CF34-10E Engine Manual, for combustor cases, part number (P/N) 2070M47G02 and P/N 2070M47G03, from 39,600 cycles-since-new (CSN) to 24,600 CSN.

(g) The requirements of this AD have been met when the engine manual changes are made and operators have modified their continuous airworthiness maintenance plans to reflect the Engine Maintenance Program requirements specified in the GE CF34-10E Engine Manual.

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 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 May 30, 2007.

Robert Ganley,

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