AD 97-21-07 R1

On October 8, 1997, the Federal Aviation Administration (FAA) issued AD 97-21-07, Amendment 39-10160 (62 FR 53935, October 17, 1997), applicable to AlliedSignal Inc. (formerly Textron Lycoming) Model T5313B, T5317A, and T53 series military turboshaft engines approved for installation on aircraft certified in accordance with Section 21.25 of the Federal Aviation Regulations (FAR), to require a one-time visual inspection of accessory drive carrier assemblies for affected serial numbers (S/Ns) designating a potentially defective assembly, and if the S/N is applicable, replacement with a serviceable assembly. That action was prompted by a report of an N2 overspeed condition on an AlliedSignal Inc. Model T5317A-1 turboshaft engine. That condition, if not corrected, could result in accessory drive carrier assembly failure, which could result in an N2 overspeed and an uncontained engine failure. Since the issuance of that AD, the FAA has been informed that themilitary helicopter models that incorporate this engine installation had been omitted from the sentence in the Applicability paragraph of the AD that provides guidance as to the helicopter models with the affected engines, and that a civilian helicopter model, the Kaman Aircraft Corp. K-1200 series helicopter, should be removed from the list. The military helicopter models, certified in accordance with Section 21.25 of the FAR, are: the UH-1A through E; UH-1G, H, L, M; AH-1F, Q, G, S; HH-1H, K; TH-1L; OV-1C, D; and HH-43. This revised AD makes these changes to the Applicability paragraph. All mandatory actions required by the AD remain the same. The FAA has reviewed and approved the technical contents of AlliedSignal Inc. Alert Service Bulletin (ASB) No. T5313B/17A-A0092, Revision 1, dated July 1, 1997; ASB No. T53-L-13B-A0092, dated June 4, 1997; and ASB No. T53-L-703-A0092, dated June 4, 1997. These ASBs describe procedures for performing a one-time visual inspection of accessory drive carrier assemblies for affected S/Ns designating a defective assembly, and if the S/N is applicable, replacement with a serviceable assembly. Since an unsafe condition has been identified that is likely to exist or develop on other engines of this same type design, this AD revises AD 97-21-07 to add military helicopter models and remove one civilian helicopter model from the sentence in the Applicability paragraph of the AD that provides guidance as to the helicopter models with the affected engines. The actions are required to be accomplished in accordance with the ASBs described previously. Since a situation exists that allows the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are unnecessary, and that good cause exists for making this amendment effective in less than 30 days. Comments Invited Although this action is in the form of a final rule that involves requirements affecting flight safety and,thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date forcomments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 97-ANE-38-AD." The postcard will be date stamped and returned to the commenter. The regulations adopted herein will not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. The FAA has determined that this regulation is anemergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption of the Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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 [Amended] 2. Section 39.13 is amended by removing Amendment 39-10160 (62 FR 53935, October 17, 1997) and by adding a new airworthiness directive, Amendment 39-10610, to read as follows: