Discussion
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 was published in the Federal Register on April 17, 2009 (74 FR 17797). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:
Cycle life limit value for ARRIUS 1A balancing piston Part Number (P/N) 0 319 20 152 0, initially set at 40 000 cycles, has been reduced to 16 000 cycles, following the discovery of a calculation error during a recent review of the ARRIUS 1 engine family files.
As of the publication date of this Airworthiness Directive, no ARRIUS 1A engines in service are fitted with a balancing piston that has logged more than 16 000 cycles, and the outlook for the consumption of cycles on the ARRIUS 1A fleet indicates that no balancing pistons will exceed this new limit for a few years' time.
Moreover, this new cycle life limit value for the balancing piston has been incorporated since the end of 2007 in ARRIUS 1A Maintenance documentation.
Failure to comply with the new life limits provided in the Airworthiness Limitations Section of ARRIUS 1A Maintenance documentation could potentially result in an engine in-flight- shutdown and the release of high energy debris.
You may obtain further information by examining the MCAI in the AD docket.
Comments
We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.
Conclusion
We reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.
Differences Between This AD and the MCAI or Service Information
The MCAI requires modifying the cyclic life limit value of the balancing piston in the engine log book as specified in Turbomeca Mandatory Service Bulletin 319 72 0811, dated April 30,2008, and updating the approved operator's maintenance program.
We are requiring removing from service ARRIUS 1A engines containing a balancing piston, P/N 0 319 20 152 0, before the balancing piston meets or exceeds the new, reduced cyclic life limit value of 16,000 cycles-since-new.
Costs of Compliance
Based on the service information, we estimate that this AD would affect about 33 products of U.S. registry. We also estimate that it would take about 0.5 work-hour per product to comply with this AD. The average labor rate is $80 per work-hour. Required parts would cost about $5,280 per product. Based on these figures, we estimate the cost of the AD on U.S. operators to be $175,560.
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 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 this 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. 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 regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket.
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 AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone (800) 647-5527) is provided in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.
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 FAA 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.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by adding the following new AD: