Discussion \n\n\n\tThe FAA issued AD 2012-22-05, Amendment 39-17241 (77 FR 68052, November 15, 2012) (''AD 2012-22-05''), and AD 2018-19-03, Amendment 39-19403 (83 FR 46859, September 17, 2018) (''AD 2018-19-03''), which applied to certain Fokker Services B.V. Model F28 Mark 0070 and 0100 airplanes. AD 2012-22-05 required inspecting for cracks of the pistons on the MLG, and replacing the affected pistons if necessary. AD 2012- 22-05 also required modifying the MLG, and revising the airplane maintenance program. AD 2018-19-03 required an inspection of the MLG, and replacement if necessary. The FAA issued these ADs to address MLG failure during the landing roll-out, which could result in damage to the airplane and injury to occupants. \n\nActions Since ADs 2012-22-05 and 2018-19-03 Were Issued \n\n\n\tSince ADs 2012-22-05 and 2018-19-03 were issued, the FAA has received a report of a crack found in the lower portion of a left-hand MLG piston; one possible factor was hydrogen-assisted cracking. The FAA determined that the cracked piston was part of a batch of six MLG pistons on which the required heat treatments may not have been applied during overhaul. Another possible contributing factor is that the wire harness port of the MLG piston is a highly stressed area, prone to high-rate crack growth if small surface imperfections are present. \n\tThe EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2019-0224, dated September 6, 2019 (''EASA AD 2019-0224'') (also referred to as the Mandatory Continuing Airworthiness Information, or ''the MCAI''), to correct an unsafe condition for all Fokker Services B.V. Model F28 Mark 0070 and 0100 airplanes. EASA AD 2019-0224 supersedes EASA ADs 2011-0159 and 2017- 0163 (which correspond to FAA ADs 2012-22-05 and 2018-19-03). \n\tThis AD was prompted by a report of a crack found in the lower portion of a left-hand MLG piston, and a determination that the required heat treatment may not have been applied to certain MLG pistons. See the MCAI for additional background information. \n\n((Page 13476)) \n\nExplanation of Retained Requirements \n\n\n\tAlthough this AD does not explicitly restate the requirements of AD 2012-22-05 this AD retains all of the requirements of AD 2012-22-05. Those requirements are referenced in EASA AD 2019-0224, which, in turn, is referenced in paragraph (g) of this AD. This AD retains none of the requirements of AD 2018-19-03. \n\nRelated IBR Material Under 1 CFR Part 51 \n\n\n\tEASA AD 2019-0224 describes procedures for repetitive inspections of the MLG pistons for cracks, replacing cracked MLG pistons, and modifying the MLG by replacing each affected part (MLG piston or MLG unit) with a serviceable part or replacing each affected MLG unit with a serviceable unit. \n\tThis material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified inthe ADDRESSES section. \n\nFAA's Determination \n\n\n\tThis product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to a bilateral agreement with the State of Design Authority, the FAA has been notified of the unsafe condition described in the MCAI referenced above. The FAA is issuing this AD because the agency evaluated all pertinent information and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design. \n\nRequirements of This AD \n\n\n\tThis AD requires accomplishing the actions specified in EASA AD 2019-0224 described previously, as incorporated by reference, except for any differences identified as exceptions in the regulatory text of this AD. \n\nExplanation of Required Compliance Information \n\n\n\tIn the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA initially worked with Airbus and EASA to develop a process to usecertain EASA ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has since coordinated with other manufacturers and civil aviation authorities (CAAs) to use this process. As a result, EASA AD 2019-0224 is incorporated by reference in this AD. This AD, therefore, requires compliance with EASA AD 2019-0224 in its entirety, through that incorporation, except for any differences identified as exceptions in the regulatory text of this AD. Using common terms that are the same as the heading of a particular section in the EASA AD does not mean that operators need comply only with that section. For example, where the AD requirement refers to ''all required actions and compliance times,'' compliance with this AD requirement is not limited to the section titled ''Required Action(s) and Compliance Time(s)'' in the EASA AD. Service information specified in EASA AD 2019-0224 that is required for compliance with EASA AD 2019-0224 will be available on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0105 after the FAA final rule is published. \n\nFAA's Justification and Determination of the Effective Date \n\n\n\tSince there are currently no domestic operators of these products, notice and opportunity for public comment before issuing this AD are unnecessary. In addition, for the reasons stated above, the FAA finds that good cause exists for making this amendment effective in less than 30 days. \n\nComments Invited \n\n\n\tThis AD is a final rule that involves requirements affecting flight safety, and the FAA did not precede it by notice and opportunity for public comment. The FAA invites you to send any written relevant data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include ''Docket No. FAA-2020-0105; Product Identifier 2019-NM-172-AD'' at the beginning of your comments. The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of this AD. The FAA will consider all comments received by the closing date and may amend this AD based on those comments. \n\tThe 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 AD. \n\nCosts of Compliance \n\n\n\tCurrently, there are no affected U.S.-registered airplanes. If an affected airplane is imported and placed on the U.S. Register in the future, the FAA provide the following cost estimates to comply with this AD: \n\n\n\tEstimated Costs for Required Actions ---------------------------------------------------------------------------------------------------------------- \n\tCost per \n\tAction Labor cost Parts cost product ---------------------------------------------------------------------------------------------------------------- Retained actions from AD 2012-22-05........... 24 work-hours x $85 per hour = $0 $2,040 \n\t$2,040. New actions................................... 24 work-hours x $85 per hour = 0 2,040 \n\t$2,040. ---------------------------------------------------------------------------------------------------------------- \n\n\n\tThe FAA has received no definitive data that would enable the agency to provide cost estimates for the on-condition actions specified in this AD. \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\tThe FAA has determined that 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 \n\n((Page 13477)) \n\npower 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, \n\t(2) Will not affect intrastate aviation in Alaska, and \n\t(3) 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. \n\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.