Discussion \n\n\n\tThe EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2020-0073, dated March 26, 2020 (''EASA AD 2020-0073'') (also referred to as the Mandatory Continuing Airworthiness Information, or ''the MCAI''), to correct an unsafe condition for all Airbus SAS Model A318-111, -112, -121, and -122 airplanes; Model A319-111, -112, -113, -114, -115, -131, -132, -133, - 151N, -153N, and -171N airplanes; Model A320-211, -212, -214, -215, - 216, -231, -232, -233, -251N, -252N, -253N, -271N, -272N, and -273N airplanes; and Model A321-111, -112, -131, -211, -212, -213, -231, - 232, -251N, -251NX, -252N, -252NX, -253N, -253NX, -271N, -271NX, -272N, and -272NX airplanes. (Model A320-215 airplanes are not certified by the FAA and are not included on the U.S. type certificate data sheet; this AD therefore does not include those airplanes in the applicability.) \n\tThis AD was prompted by a recent maintenance repair organization's report to Airbus of deviations from the acceptance test procedure for certain THSAs as specified in the Airbus component maintenance manual (CMM) after disassembly and reassembly of the THSA ball screw sub- assembly. A deviation from the accepted test procedure affects, in particular, the verification of proper installation of the THSA ball screw in shop. Improper installation of the THSA ball screw jack compromises the fail safe design of the THSA that prevents the axial separation of the screw shaft. Subsequent missed inspections or testing regimes further compromise the fail safe design of the THSA. A compromised fail safe design of the THSA can result in a single failure of the THSA. The FAA is issuing this AD to address this unsafe condition, which can compromise fail safe design of the THSA, which may result in uncontrolled movement of the horizontal stabilizer as a result of a single failure, and consequent loss of control of the airplane. See the MCAI for additional background information. \n\nRelated IBR Material Under 1 CFR Part 51 \n\n\n\tEASA AD 2020-0073 describes procedures for replacing affected THSAs with serviceable THSAs. 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. \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 the FAA's 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 2020-0073 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 use certain 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 2020-0073 is incorporated by reference in this final rule. This AD, therefore, requires compliance with EASA AD 2020-0073 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 2020-0073 that is required for compliance with EASA AD 2020-0073 is available on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0210. \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.) 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 seeking comment prior to the rulemaking. Similarly, Section 553(d) of the APA authorizes agencies to make \n\n((Page 18430)) \n\nrules 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 because, as described in the Discussion section of this AD, improper installation of THSA ball screw jack compromises fail safe design of the THSA, which can result in uncontrolled movement of the horizontal stabilizer as a result of a single failure of the THSA, and consequent loss of control of the airplane. Given the significance of the risk presented by this unsafe condition, it must be immediately addressed. \n\tAccordingly, notice and opportunity for prior public comment are impracticable pursuant to 5 U.S.C. 553(b)(3)(B). In addition, for the reasons stated above, 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. \n\nRegulatory Flexibility Act (RFA) \n\n\n\tThe requirements of the 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. \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-2020-0210; Product Identifier 2020-NM-045-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 considerall 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\tThe FAA estimates that this AD affects 89 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: \n\n\n\tEstimated Costs for Required Actions ---------------------------------------------------------------------------------------------------------------- \n\tLabor cost Parts cost Cost per product Cost on U.S. operators ---------------------------------------------------------------------------------------------------------------- Up to 13 work-hours x $85 per hour = Up $0 Up to $1,105.............. Up to $98,345. \n\tto $1,105. ---------------------------------------------------------------------------------------------------------------- \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 FAAdetermined 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 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.