AD 96-17-01 ACTIVE

This amendment adopts a new airworthiness directive (AD) that is applicable to AlliedSignal Inc. (formerly Textron Lycoming) Model T5313B turboshaft engines. This action supersedes priority letter AD 96-15-07 that currently requires, prior to further flight, removal from service of all suspect second stage power turbine disks, identified by serial number, and replacement with serviceable parts. This action corrects an incorrect second stage power turbine disk serial number. This amendment is prompted by report of a typographical error in the serial number listing. The actions specified by this AD are intended to prevent possible failure of a second stage power turbine disk, uncontained engine failure, and damage to aircraft.

Final rule; request for comments.

96-17-01 AlliedSignal Inc.: Amendment 39-9709. Docket No. 96-ANE-21. Supersedes Priority Letter AD 96-15-07, issued July 16, 1996.
Applicability: AlliedSignal Inc., (formerly Textron Lycoming) Model T5313B turboshaft engines, incorporating suspect second stage power turbine disks, Part Number (P/N) 1-140-272-04, identified by any of the following Serial Numbers:
SC05903/32891-451,
SC09442/32891-476,
SC09685/32891-623,
SC09723/32891-654,
SC09743/32891-437,
SC09759/32891-634,
SC09755/32891-637,
SC09779/32891-682,
SC09908/32891-657,
SC10100/32891-649,
SC10267/32891-573,
SC10269/32891-471.
These engines are installed on but not limited to Bell Helicopter Textron 205A-1 series rotorcraft.
Note: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that havebeen modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
Compliance: Required as indicated, unless accomplished previously.
To prevent possible failure of a second stage power turbine disk, uncontained engine failure, and damage to aircraft, accomplish the following:
(a) Prior to further flight, remove from service all suspect second stage power turbine disks, P/N 1-140-272-04, identified by Serial Numbers listed in the applicability paragraph of this AD, and replace with serviceable parts.
(b) An alternative method of compliance that provides an acceptable level of safety may be used if approved by the Manager, Engine Certification Office. The request should be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Engine Certification Office.
Note: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Engine Certification Office.
(c) This amendment supersedes priority letter AD 96-15-07, issued July 16, 1996.

On July 16, 1996, the Federal Aviation Administration (FAA) issued priority letter airworthiness directive (AD) 96-15-07, applicable to AlliedSignal Inc. (formerly Textron Lycoming) Model T5313B turboshaft engines, which requires prior to further flight, removal from service of all suspect second stage power turbine disks, identified by serial number, and replacement with serviceable parts. That action was prompted by a report that surplus military second stage power turbine disks, Part Number (P/N) 1-140-272-04, were used on civil aircraft. These disks were manufactured by a military parts supplier outside of a Federal Aviation Administration (FAA)- approved manufacturing quality system. When compared to parts manufactured for civil use, parts manufactured for military service may undergo different manufacturing procedures, and receive different quality control inspections, that are not approved by the FAA. After a review of some disk records, the FAAcannot determine whether the suspect disks conform with the FAA-approved type design for similar disks used in civil aircraft engines. Therefore, the suspect disks are currently not airworthy for use in civil engines, and must be removed from service. Twelve disks were subsequently installed in civil engines, four of these disks are currently in service. Although the FAA has not received any reports of suspect disk failures to date, it is unknown whether the suspect disks provide an acceptable level of safety for any period of operation. This condition, if not corrected, could result in possible failure of a second stage power turbine disk, uncontained engine failure, and damage to aircraft.
Since the issuance of that priority letter AD, the FAA received a report of a typographical error in the serial number listing.
Since an unsafe condition has been identified that is likely to exist or develop on other engines of this same type design, this AD supersedes priority letter AD 96-15-07 to correct an incorrect second stage power turbine disk serial number.
Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, 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 for comments, 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 96-ANE-21." 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 an emergency 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 RulesDocket. 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 USC 106(g), 40113, 44701. 39.13 - [AMENDED]
2. Section 39.13 is amended by adding the following new airworthiness directive:

Submit comments in triplicate to the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, Attention: Rules Docket No. 96-ANE-21, 12 New England Executive Park, Burlington, MA 01803-5299. Comments may also be submitted to the Rules Docket by using the following Internet address: "epd-adcomments@mail.hq.faa.gov". All comments must contain the Docket No. in the subject line of the comment.

Eugene Triozzi, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (617) 238-7148, fax (617) 238-7199.