Discussion
The FAA received reports of approximately 21 failures of the affected LPT 3rd-stage blades from 2017 through June 2019. These failures appear to be caused by impact damage occurring when debris passes through the engine. The manufacturer has determined the need to replace any affected LPT 3rd-stage blades with LPT blades made of a different material that is more resistant to impact damage.
In response to these events, the FAA issued a Notice of Proposed Rulemaking (NPRM), Product Identifier 2019-NE-31-AD (84 FR 64441, November 22, 2019), proposing to adopt a new AD to address LPT 3rd- stage blade failures on certain IAE LLC PW1122G-JM, PW1124G-JM, PW1124G1-JM, PW1127G1-JM, PW1127GA-JM, PW1127G-JM, PW1129G-JM, PW1130G- JM, PW1133GA-JM, PW1133G-JM model turbofan engines. This NPRM AD proposes removal from service of affected LPT 3rd-stage blades at the next engine shop visit.
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Since June 2019, and prior to the publication of NPRM Product Identifier 2019-NE-31-AD, 20 additional failures of the affected LPT 3rd-stage blades have occurred. The investigation of these failures is on-going. These additional failures have occurred primarily on engines operated by certain airlines. This AD requires an accelerated timeframe for replacement of the affected LPT 3rd-stage blades on certain serial- numbered engines being operated by these airlines. Based on publication of NPRM Product Identifier 2019-NE-31-AD, the FAA would still require replacement of the affected LPT 3rd-stage blades on the remaining affected engines at the next engine shop visit.
This condition, if not addressed, could result in failure of the LPT 3rd-stage blades, failure of one or more engines, loss of thrust control, and loss of the airplane. The FAA is issuing this AD to address the unsafe condition on these products.
Related Service Information
The FAA reviewed Pratt & Whitney Service Bulletin PW1000G-C-72-00- 0111-00A-930A-D, Issue No. 002, dated October 18, 2019. The service information describes procedures for removal of the affected LPT 3rd- stage blades and their replacement with parts eligible for installation.
FAA's Determination
The FAA is 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, within the times specified in the compliance section of this AD, removal from service of LPT 3rd-stage blades part number (P/N) 5387343, 5387493, 5387473, or 5387503, and their replacement with parts eligible for installation.
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 the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because no domestic operators use this product. It is unlikely that the FAA will receive any adverse comments or useful information about this AD from U.S. operators. Therefore, the FAA finds good cause that notice and opportunity for prior public comment are unnecessary. In addition, for the reason stated above, the FAA finds 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, the FAA invites you to send any written data, views, or arguments about this final rule. Send your comments to an address listed under the ADDRESSES section. Include the docket number FAA-2019- 0995 and Product Identifier AD-2019-00113-E at the beginning of your comments. The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of this final rule. The FAA will consider all comments received by the closing date and may amend this final rule because of those comments.
The FAA will post all comments received, without change, to https://www.regulations.gov, including any personal information you provide. The FAA will also post a report summarizing each substantive verbal contact received about this final rule.
Regulatory Flexibility Act
The requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without notice and comment, RFA analysis is not required.
Costs of Compliance
The FAA estimates that this AD affects 0 engines installed on airplanes of U.S. registry.
The FAA estimates the following costs to comply with this AD:
Estimated Costs ----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Action Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Replace set of LPC 3rd-stage 408 work-hours x $85 $750,000 per blade $784,680 $0
blades. per hour = $34,680. set. ----------------------------------------------------------------------------------------------------------------
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.
The FAA is 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 is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to engines, propellers, and associated appliances to the Manager, Engine and Propeller Standards Branch, Policy and Innovation Division.
Regulatory Findings
This AD will not have federalismimplications 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, and
(2) Will not affect intrastate aviation in Alaska.
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List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.