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 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2024-2313; Project Identifier MCAI-2024-00493-E; Amendment 39-22852; AD 2024-19-10]
RIN 2120-AA64
 AGENCY: Federal Aviation Administration (FAA), DOT.
 ACTION: Final rule; request for comments.
 SUMMARY: The FAA is adopting a new airworthiness directive (AD) for certain Austro Engine GmbH (Austro) Model E4 and E4P engines. This AD was prompted by reports of engine failures and an investigation where cracks were discovered on the pistons. This AD requires repetitive borescope inspections (BSIs) for cracks on the pistons, and, if necessary, removal from service and replacement of the piston, and a fuel sample analysis for water contamination and, if contamination is found, replacement of the high-pressure pump (HPP), injectors, and fuel rails. The FAA is issuing this AD to address the unsafe condition on these products.
 DATES: This AD is effective October 9, 2024. The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of October 9, 2024. The FAA must receive comments on this AD by November 8, 2024.
 ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: *Federal eRulemaking Portal:*
                         Go to 
                        *regulations.gov*. Follow the instructions for submitting comments.
                    *Fax:*
                         (202) 493-2251.
                    *Mail:*
                         U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
                    *Hand Delivery:*
                         Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
                        ( print page 77773) *AD Docket:*
                         You may examine the AD docket at 
                        *regulations.gov*
                         under Docket No. FAA-2024-2313; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above. *Material Incorporated by Reference:* For Austro material identified in this AD, contact Austro, Rudolf-Diesel-Strasse 11, A-2700 Weiner Neustadt, Austria; phone: +43 2622 23000; website:*austroengine.at*.
                    You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 1200 District Avenue, Burlington, MA 01803. For information on the availability of this material at the FAA, call (817) 222-5110. It is also available at*regulations.gov*
                         under Docket No. FAA-2024-2313.
 FOR FURTHER INFORMATION CONTACT: Morton Lee, Aviation Safety Engineer, FAA, 1200 District Avenue, Burlington, MA 01803; phone: (860) 386-1791; email: 
                        *morton.y.lee@faa.gov*.


SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written data, views, or arguments about this final rule. Send your comments to an address listed under 
                    **ADDRESSES**
                    . Include “Docket No. FAA-2024-2313; Project Identifier MCAI-2024-00493-E” at the beginning of your comments. The most helpful comments reference a specific portion of the final rule, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this final rule because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to 
                    *regulations.gov*, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this final rule. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this AD contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this AD, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this AD. Submissions containing CBI should be sent to Morton Lee, Aviation Safety Engineer, FAA, 1200 District Avenue, Burlington, MA 01803. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background The European Union Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA Emergency AD 2024-0172-E, dated August 28, 2024 (EASA AD 2024-0172-E) (also referred to as the MCAI), to correct an unsafe condition on certain Austro Model E4 and E4P engines having a piston part number (P/N) E4A-72-400-000. The MCAI states that engine failures have been reported, where, during subsequent inspection, cracks on the piston were identified. During the following investigation, it was determined that only affected parts (pistons P/N E4A-72-400-000) are subject to that failure. Further investigation is on-going to determine the root cause of that failure. This condition, if not corrected, could lead to engine failure with consequent reduced control of the airplane and, for single-engine airplanes, damage to the airplane and injury to occupants during an emergency landing. You may examine the MCAI in the AD docket at 
                    *regulations.gov*
                     under Docket No. FAA-2024-2313. Material Incorporated by Reference Under 1 CFR Part 51 The FAA reviewed Austro Mandatory Service Bulletin No. MSB-E4-043/0, dated August 27, 2024, which specifies, among other things, procedures for repetitive BSIs for cracks on the pistons. This material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the 
                    **ADDRESSES**
                     section. FAA's Determination These products have been approved by the aviation authority of another country and are approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI and material referenced above. The FAA is issuing this AD after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design. AD Requirements This AD requires repetitive BSIs for cracks on the pistons and, if necessary, removal from service and replacement of the piston, and a fuel sample analysis for water contamination and, if contamination is found, replacement of the HPP, injectors, and fuel rails. Interim Action The FAA considers that this AD is an interim action. The unsafe condition is still under investigation by the manufacturer and, depending on the results of that investigation, the FAA may consider further rulemaking action. Justification for Immediate Adoption and Determination of the Effective Date Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 551 
                    *et seq.*) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for “good cause,” finds that those procedures are “impracticable, unnecessary, or contrary to the public interest.” Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause. An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies forgoing notice and comment prior to adoption of this rule because cracks on the pistons, if not corrected, could lead to engine failure with consequent reduced control of the airplane and, for single-engine airplanes, damage to the airplane and injury to occupants during an emergency landing. The FAA has determined that these engines will need to be inspected before 100 or 200 flight hours after installation depending on the engine model. Based on the fleet usage of these engines, many of these engines will need an inspection before further flight and most within 3 months. These compliance times are shorter than the time necessary for the public to comment and for publication of the final 
                    ( print page 77774)
                    rule. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b). In addition, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days, for the same reasons the FAA found good cause to forgo notice and comment. 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 prior notice and comment, RFA analysis is not required. Costs of Compliance The FAA estimates that this AD affects 20 engines installed on airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: Estimated Costs
Action
Labor cost
Parts cost
Cost per
                             product
Cost on U.S.
                             operatorsPerform BSI of the piston
5 work-hours × $85 per hour = $425
$0
$425
$8,500
 The FAA estimates the following costs to do any necessary replacements and follow-on inspections that would be required based on the results of the inspection. The agency has no way of determining the number of engines that might need these replacements and follow-on inspections. On-Condition Costs
Action
Labor cost
Parts cost
Cost per productReplace the piston
60 work-hours × $85 per hour = $5,100
$2,216
$7,316Perform fuel sample analysis
1 work-hours × $85 per hour = $85
0
85Replace the injectors, HPP, and fuel rails
60 work-hours × $85 per hour = $5,100
2,216
7,316
 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. 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, and (2) Will not affect intrastate aviation in Alaska. List of Subjects in 14 CFR Part 39 Air transportation
Aircraft
Aviation safety
Incorporation by reference
Safety
 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. § 39.13
 2.The FAA amends § 39.13 by adding the following new airworthiness directive: **2024-19-10 Austro Engine GmbH:**
                             Amendment 39-22852; Docket No. FAA-2024-2313; Project Identifier MCAI-2024-00493-E. (a) Effective Date This airworthiness directive (AD) is effective October 9, 2024. (b) Affected ADs None. (c) Applicability This AD applies to Austro Engine GmbH (Austro) Model E4 and E4P engines with an installed piston having part number E4A-72-400-000. (d) Subject Joint Aircraft System Component (JASC) Code 8500, Engine (Reciprocating). (e) Unsafe Condition This AD was prompted by reports of engine failures and an investigation where cracks were discovered on the pistons. The FAA is issuing this AD to detect and address cracks on the pistons. The unsafe condition, if not addressed, could result in engine failure with consequent reduced control of the airplane and, for single-engine airplanes, damage to the airplane and injury to occupants during an emergency landing. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions (1) At the applicable times specified in paragraphs (g)(1)(i) through (iv) of this AD, do repetitive borescope inspections (BSIs) of each affected piston for cracks on the piston in accordance with paragraph 2.1.2 “Accomplishment/Instructions” of Austro Mandatory Service Bulletin No. MSB-E4-043/0, dated August 27, 2024. (i) For Configuration E4A and E4P engines with less than 100 flight hours (FHs) since installation as of the effective date of this AD: Inspect within 100 FHs since installation and thereafter at intervals not to exceed 50 FHs.
                            ( print page 77775) (ii) For Configuration E4A and E4P engines with 100 FHs or more since installation as of the effective date of this AD: Inspect before further flight and thereafter at intervals not to exceed 50 FHs. (iii) For Configuration E4B and E4C engines with less than 200 FHs since installation as of the effective date of this AD: Inspect within 200 FHs since installation and thereafter at intervals not to exceed 100 FHs. (iv) For Configuration E4B and E4C engines with 200 FHs or more since installation as of the effective date of this AD: Inspect before further flight and thereafter at intervals not to exceed 100 FHs. (2) If during any BSI required by paragraph (g)(1) of this AD, any crack is found, before further flight, do the following: (i) Remove from service and replace the piston. Replacement of the engine core includes piston replacement and would satisfy this requirement. (ii) Collect a fuel sample from the high-pressure pump (HPP) fuel return line and do a fuel analysis for water contamination. (iii) If during any fuel analysis required by paragraph (g)(2)(ii), any water contamination is found, remove from service and replace the HPP, injectors, and fuel rails. (h) Definitions For the purpose of this AD: (1) “Configuration E4A engines” are Model E4 engines with an engine serial number (ESN) that begins with “E4-A- . . .” (2) “Configuration E4B engines” are Model E4 engines with an ESN that begins with “E4-B- . . .” (3) “Configuration E4C engines” are Model E4 engines with an ESN that begins with “E4-C- . . .” (4) “Configuration E4P engines” are Model E4P engines with an ESN that begins with “E4P-B- . . .” or “E4P-C- . . .” (i) Credit for Previous Actions Credit may be taken for BSIs done before the effective date of this AD using Austro Engine Authorization Request/Occurrence Reporting AR1734, dated August 16, 2024. (j) Special Flight Permits A special flight permit may be issued in accordance with 14 CFR 21.197 and 21.199 to permit a single ferry flight to a location where the actions required by this AD can be accomplished, provided that the flight is accomplished under visual flight rule conditions, without passengers, and does not exceed 3 FHs. (k) Alternative Methods of Compliance (AMOCs) (1) The Manager, International Validation Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the International Validation Branch, send it to the attention of the person identified in paragraph (l) of this AD and email to: 
                            *AMOC@faa.gov.* (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. (l) Additional Information For more information about this AD, contact Morton Lee, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (860) 386-1791; email: 
                            *morton.y.lee@faa.gov*. (m) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this material as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Austro Engine GmbH (Austro) Mandatory Service Bulletin No. MSB-E4-043/0, dated August 27, 2024. (ii) [Reserved] (3) For Austro material identified in this AD, contact Austro, Rudolf-Diesel-Strasse 11, A-2700 Weiner Neustadt, Austria; phone: +43 2622 23000; website: 
                            *austroengine.at.* (4) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 1200 District Avenue, Burlington, MA 01803. For information on the availability of this material at the FAA, call (817) 222-5110. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit 
                            *www.archives.gov/​federal-register/​cfr/​ibr-locations*
                             or email 
                            *fr.inspection@nara.gov*. Issued on September 17, 2024. Victor Wicklund, Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.


[FR Doc. 2024-21804 Filed 9-19-24; 4:15 pm] BILLING CODE 4910-13-P