Discussion
We received a report of an HET turbocharger turbine wheel that failed a static strength test at its manufacturing facility. Subsequent tests showed that nearly all turbine wheels, P/N 410188-0019, had significant cracking under the surface of a critical weld joint between the turbine wheel head and shaft that occurred during manufacturing. HET has identified by serial number (S/N) the turbochargers shipped from the factory with this unsafe condition. HET has also identified the S/N range of affected turbine wheels. Some of the affected turbine wheels became available for overhaul or field repair since August 29, 2012, and may have been installed. This condition, if not corrected, could result in turbocharger turbine wheel failure, reduction or complete loss of engine power, loss of engine oil, oil fire, and damage to the airplane.
Relevant Service Information
We reviewed HET Alert Service Bulletin (ASB) No. 048, dated November16, 2012. The ASB lists the known serial numbers of affected turbochargers.
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FAA's Determination
We are issuing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.
AD Requirements
This AD requires removing the affected turbochargers from service before further flight.
FAA's Justification and Determination of the Effective Date
An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because HET cannot confirm the affected turbochargers can safely be used. Therefore, we find that notice and opportunity for prior public comment are impracticable and that good cause exists for making this amendment effective in less than 30 days.
Comments Invited
This AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment. However, we invite you to send any written data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number FAA-2012-1245 and Directorate Identifier 2012-NE-41-AD at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because 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 we receive about this AD.
Costs of Compliance
We estimate that this AD affects 56 airplanes of U.S. registry with affected turbochargers installed. We also estimate that it will take about 4 hours to remove a turbocharger from service. The average labor rate is $85 per hour. Based on these figures, we estimate the total cost of the AD to U.S. operators to be $19,040.
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
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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, 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
0 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]
0 2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD):