Background \n\n\n\tEASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2018-0284, dated December 20, 2018 (EASA AD 2018-0284), to correct an unsafe condition for Airbus Helicopters Deutschland GmbH (AHD) Model EC135 P1, EC135 P2, EC135 P2+, EC135 P3, EC135 T1, EC135 T2, EC135 T2+, EC135 T3, EC635 P2+, EC635 P3, EC635 T1, EC635 T2+, and EC635 T3 helicopters. Model EC635 P2+, EC635 P3, EC635 T1, and EC635 T3 helicopters are not certificated by the FAA and are not included on the U.S. type certificate data sheet; this AD therefore does not include those helicopters in the applicability. \n\tThe FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters. The NPRM published in the Federal Register on March 30, 2021 (86 FR 16550). The NPRM was prompted by a report of increased control force in the collective axis on an AHD Model EC135 helicopter. Subsequent inspections determined that a nut on a piston of the MRA had cracked and separated from the piston rod. The NPRM proposed to require a one- time visual inspection of the MRA, as specified in an EASA AD. \n\tThe FAA is issuing this AD to prevent failure of the MRA and subsequent loss of control of the helicopter. See EASA AD 2018-0284 for additional background information. \n\nDiscussion of Final Airworthiness Directive \n\nComments \n\n\n\tThe FAA gave the public the opportunity to participate in developing this final rule. The FAA received no comments on the NPRM or on the determination of the cost to the public. \n\nConclusion \n\n\n\tThe FAA reviewed the relevant data and determined that air safety and the public interest require adopting this final rule as proposed. \n\nRelated Service Information Under 1 CFR Part 51 \n\n\n\tEASA AD 2018-0284 describes procedures for a one-time visual inspection of the MRA and depending on the results, replacing the affected parts. \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 in the ADDRESSES section. \n\nDifferences Between This AD and the EASA AD \n\n\n\tThe EASA AD requires contacting Airbus Helicopters or replacing an affected part, whereas this AD requires performing the corrective action in accordance with FAA-approved procedures or removing the affected parts from service instead. Where the EASA AD specifies a compliance time for the inspection in terms of calendar time or flight hours, this AD requires a compliance time in terms of hours time-in- service instead. Where the EASA AD specifies a compliance time of 15 days for reporting the inspection results, this AD requires that the findings be reported within 30 days. \n\nInterim Action \n\n\n\tThe FAA considers this AD interim action. If final action is later identified, \n\n((Page31088)) \n\nthe FAA might consider further rulemaking then. \n\nCosts of Compliance \n\n\n\tThe FAA estimates that this AD affects 331 helicopters of U.S. Registry. Labor rates are estimated at $85 per work-hour. Based on these numbers, the FAA estimates that operators may incur the following costs in order to comply with this AD. \n\tInspecting the nuts on the MRA pistons takes about 1 work-hour for an estimated cost of $85 per helicopter and $28,135 for the U.S. fleet. Replacing the MRA takes about 7 work-hours and parts cost $325,081 for an estimated cost of $325,676 per helicopter. Repairing the MRA takes up to about 8 work-hours and parts cost about $110 for an estimated cost of up to $790 per MRA. Reporting information takes about 1 hour for an estimated cost of $85 per helicopter and $28,135 for the U.S. fleet. \n\nPaperwork Reduction Act \n\n\n\tA federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB control number. The control number for the collection of information required by this AD is 2120- 0056. The paperwork cost associated with this AD has been detailed in the Costs of Compliance section of this document and includes time for reviewing instructions, as well as completing and reviewing the collection of information. Therefore, all reporting associated with this AD is mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to Information Collection Clearance Officer, Federal Aviation Administration, 10101 Hillwood Pkwy., Fort Worth, TX 76177-1524. \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, \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.