AD 2012-01-10

This AD is effective February 27, 2012.

For service information identified in this AD, contact GE-Aviation, M/D Rm. 285, One Neumann Way, Cincinnati, OH 45215, phone: (513) 552-3272; email: geae.aoc@ge.com. You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call (781) 238-7125.

John Frost, Aerospace Engineer, Engine Certification Office, FAA, 12 New England Executive Park, Burlington, MA 01803; phone: (781) 238-7756; fax: (781) 238-7199; email: john.frost@faa.gov.

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM published in the Federal Register on October 18, 2011 (76 FR 64287). That NPRM proposed to require removing from service all CVD support assemblies and any fan drive shaft on the affected engines if wear is found on either the CVD support ring or the inside diameter of the fan drive shaft.

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal and the FAA's response to each comment.

One commenter, Embraer Aircraft Maintenance Services, requests that we include engine S/N 994187 in the applicability. They cite the GE All Operators Wire they received as being accurate with the affected engine S/Ns, which includes S/N 994187.

We agree. We added S/N 994187.

One commenter, GE, requests that we allow previous credit for engines with records of prior CVD support assembly replacement and fan drive shaft inspection per the Engine Manual, before the effective date of the AD.

We agree that previous credit should be allowed. Paragraph (e) of the AD requires compliance before accumulating 11,500 total cycles-in-service on the engine, unless already done. We did not change the AD.

We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting the AD with the change described previously.

We estimate that this AD will affect 71 GE CF34-10E series turbofan engines installed on airplanes of U.S. registry. We also estimate that it will take about 8 work-hours per engine to perform a replacement of the CVD support assembly and visual inspections, and that the average labor rate is $85 per work-hour. A replacement CVD support assembly costs about $3,080. We estimate that two fan drive shafts will fail inspection and require replacement. A replacement fan drive shaft costs about $126,900. We estimate that no additional labor costs would be incurred to perform the required part replacements as the replacements are done at time of scheduled engine shop visit. Based on these figures, we estimate the total cost of the AD to U.S. operators to be $520,760.

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.

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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

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

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):