Background \n\n\n\tThe European Union Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, issued EASA Emergency AD 2021-0055-E, dated February 25, 2021. EASA Emergency AD 2021-0055-E was revised by EASA AD 2021-0055R1, dated March 10, 2021. EASA AD 2021-0055R1 was superseded by EASA AD 2021-0094, dated March 31, 2021 (referred to after this as ''the MCAI''), to address the unsafe condition on these products. The MCAI states: \n\n\n\tOccurrences were reported of oil pump blockage on E4-A and E4-B engines. Subsequent investigation determined that the blockage was caused by oil contamination with casting sand from the production process of oil pump P/N E4A-50-000-BHY. A blocked oil pump causes failure of the engine lubrication system. The root cause was found in the sand casted oil pump housing cleaning process, which was not properly performed. \n\tThis condition, if not corrected, could lead to engine in-flight shut-down with consequent forced landing, possibly resulting in damage to the aeroplane and injury to occupants. \n\tTo address this potential unsafe condition, Austro Engine published the SB at original issue (later revised to add affected part s/n) to provide instructions to replace the affected oil pumps, and EASA issued AD 2021-0055-E to require replacement of affected parts, and replacement of the oil and filter. \n\n((Page 21638)) \n\nSubsequently, (EASA) AD 2021-0055R1 was issued to refer to the SB at Revision 2, where certain engines were removed from the applicability. The SB at Revision 2 also expanded the list of affected part s/n, but without impact on (EASA) AD compliance, as all added s/n were still in stock and would not be delivered to operators anymore. Since that (EASA) AD was issued, it was determined that affected parts are installed on additional engines, and Austro Engine published the SB at Revision 3 to correct the list of affected engine s/n. An additional oil pump replacement option was introduced with SB Revision 4 (with no further change to the list of affected engines/parts). \n\tFor the reason described above, this (EASA) AD retains the requirements of EASA AD 2021-0055R1, which is superseded, and refers to the SB at Revision 4 (including the additional engine s/n and the new oil pump replacement option). This (EASA) AD also expands the Applicability to include all engines where the affected part is eligible for installation, and prohibits (re)installation of an affected part on all engines. \n\n\n\tYou may obtain further information by examining the MCAI in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0311. \n\nFAA's Determination \n\n\n\tThis product has been approved by EASA and is approved for operation in the United States. Pursuant to our bilateral agreement with the European Community, EASA has notified the FAA of the unsafe condition described in the MCAI and service information. The FAA is issuing this AD because the agency evaluated all the relevant information provided by EASA and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design. \n\nRelated Service Information Under 1 CFR Part 51 \n\n\n\tThe FAA reviewed Austro Engine GmbH Mandatory Service Bulletin No. MSB-E4-030/4, Revision No. 4, dated March 30, 2021 (the MSB). This service information specifies procedures for replacing the affected oil pumps installed on E4 and E4P model diesel piston engines. This service information also specifies procedures for replacing the oil filter and engine oil installed on these engines. In addition, this service information identifies the applicable serial numbers (S/Ns) of affected E4 and E4P model diesel piston engines, the affected oil pumps requiring replacement, and an additional oil pump replacement option. This service information is reasonably available because the interested parties haveaccess to it through their normal course of business or by the means identified in the ADDRESSES section. \n\nAD Requirements \n\n\n\tThis AD requires removing the affected oil pump from service and replacing it with a part eligible for installation. This AD also requires replacing the oil filter and engine oil. \n\nDifferences Between the AD and the MCAI or Service Information \n\n\n\tThe MSB specifies that the removed oil pump must be returned to Austro Engine GmbH. The MSB specifies that information, including the engine flight hours (FHs) recorded at the time of the oil pump replacement, must be sent to Austro Engine GmbH. This AD does not mandate sending the removed oil pump or information, including the engine flight hours recorded at the time of oil pump replacement, to Austro Engine GmbH. \n\tThe MSB also specifies that for all engines with 10 FHs or less, to replace the affected oil pump, oil filter, and engine oil before the next flight. Whereas, this AD requires, for Group 1 and Group 2 engines with 10 FHs or less, replacement of the affected oil pump, oil filter, and engine oil within 30 days, before accumulating 10 FHs, or during the next scheduled maintenance, whichever occurs first after the effective date of this AD. \n\nInterim Action \n\n\n\tThe FAA considers this AD an interim action. If final action is later identified, the FAA might consider further rulemaking. \n\nJustification for Immediate Adoption and Determination of the Effective Date \n\n\n\tSection 553(b)(3)(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. \n\tAn 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 foregoing notice and comment prior to adoption of this rule. The FAA received reports of an oil pump blockage on the E4, configured as E4-A and E4-B, model diesel piston engines. The manufacturer subsequently determined that the blockage was caused by oil contamination with casting sand from the production process of the oil pump. Austro Engine issued service information providing instructions for replacement of a certain oil pump, oil filter, and engine oil installed on E4 and E4P model diesel piston engines. \n\tA blocked oil pump can result in failure of the engine lubrication system, resulting in failure of the engine, in-flight shutdown, and loss of the airplane. The FAA considers a blocked oil pump to bean urgent safety issue that requires immediate action to avoid loss of the airplane. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b)(3)(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 forego notice and comment. \n\nComments Invited \n\n\n\tThe 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-2021-0311 and Project Identifier MCAI-2021-00244-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. \n\tExcept 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 https://www.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. \n\nConfidential Business Information \n\n\n\tCBI 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, \n\n((Page 21639)) \n\nthat 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 submissioncontaining 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 Wego Wang, Aviation Safety Engineer, ECO Branch, 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. \n\nRegulatory Flexibility Act \n\n\n\tThe 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 FAA has determined that it has good cause to adopt this rule without prior notice and comment, RFA analysis is not required. \n\nCosts of Compliance \n\n\n\tThe FAA estimates that this AD affects 55 engines installed on airplanes of U.S. registry. \n\tThe FAA estimates the following costs to comply with this AD: \n\n\n\tEstimatedCosts ---------------------------------------------------------------------------------------------------------------- \n\tCost per Cost on U.S. \n\tAction Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Remove and replace the oil pump, oil 16 work-hours x $85 per $1,488 $1,360 $74,800 \n\tfilter, and engine oil. hour = $1,360. ---------------------------------------------------------------------------------------------------------------- \n\n\n\tThe FAA has included all known costs in its cost estimate. According to the manufacturer, however, some of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected operators. \n\nAuthority for This Rulemaking \n\n\n\tTitle 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. \n\tThe 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. \n\nRegulatory Findings \n\n\n\tThis 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. \n\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a ''significant regulatory action'' under Executive Order 12866, and \n\t(2) Will not affect intrastate aviation in Alaska. \n\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.