Discussion
On June 10, 2014, we issued Emergency AD 2014-12-52, which requires, before further flight, a review of the engine logbook maintenance records to determine if any affected engines are installed. Emergency AD 2014-12-52 also required for two-engine airplanes or for three-engine airplanes, that have two or more engines installed with LPT2 blades installed that have less than 250 operating hours since new, remove all affected engines before further flight. Emergency AD 2014-12-52 was sent previously to all known U.S. owners and operators of these TFE731-4, -4R, -5AR, -5BR, -5R, -20R, -20AR, -20BR, -40, - 40AR, -40R, -40BR, -50R, and -60 turbofan engines. This action was prompted by reports of LPT2 blade separations. Analysis indicates the presence of casting anomalies at or near the root of the LPT2 blade. This condition, if not corrected, could result in LPT2 blade failure, multiple engine in-flight shutdowns, and damage to the airplane. We are superseding Emergency AD
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2014-12-52 to clarify the intent of paragraphs (e) and (f) of this AD.
Relevant Service Information
We reviewed Honeywell Alert Service Bulletin (ASB) No. TFE731-72- A3792, dated June 5, 2014; ASB No. TFE731-72-A5242, dated June 5, 2014; and ASB No. TFE731-72-A5243, dated June 5, 2014. The service information describes procedures for identifying affected engines and follow-on actions.
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, before further flight, a review of the engine logbook maintenance records to determine if any affected engines are installed. If any affected engines are installed, then this AD prohibits operation of an airplane with two or more affected engines that have LPT2 bladeswith less than 250 operating hours since new.
Differences Between This AD and the Service Information
Paragraphs (e)(2) and (e)(3) of this AD require that certain affected engines be removed before further flight. Honeywell ASB No. TFE731-72-A3792, dated June 5, 2014; ASB No. TFE731-72-A5242, dated June 5, 2014; and ASB No. TFE731-72-A5243, dated June 5, 2014, for airplanes having only one affected engine installed, require no action at this time and may continue operation.
Interim Action
We consider this AD to be an interim action. We anticipate that further AD action will follow.
FAA's 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 of compliance requirement before further flight. 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 ``Docket No. FAA-2014-0386; Directorate Identifier 2014-NE-09-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 50 engines installed on airplanes of U.S. registry. We also estimate that it will take about 18 hours per engine to comply with this AD. The average labor rate is $85 per hour. Required parts cost about $0 per engine. Based on these figures, we estimate the cost of this AD on U.S. operators to be $76,500.
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 Administratorfinds 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 to the extent that it justifies making a regulatory distinction, 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.