[Federal Register Volume 62, Number 44 (Thursday, March 6, 1997)] [Rules and Regulations] [Pages 10201-10202] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 97-5512] ======================================================================= ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. 96-ANE-08; Amendment 39-9926; AD 97-04-03] RIN 2120-AA64 Airworthiness Directives; AlliedSignal Inc. TFE731 Series Turbofan Engines AGENCY: Federal Aviation Administration, DOT. ACTION: Final rule. ----------------------------------------------------------------------- SUMMARY: This amendment adopts a new airworthiness directive (AD), applicable to AlliedSignal Inc. TFE731 series turbofan engines, that requires removal from service of certain first stage low pressure turbine (LPT) seal plates prior to accumulating the new, reduced cyclic life limit, and replacement with serviceable LPT seal plates. This amendment is prompted by a report that the machined LPT seal plate geometry did not meet the design intent due to drawing ambiguity. The actions specified by this AD are intended to prevent fatigue cracking and subsequent uncontained failure of an LPT seal plate. DATES: Effective May 5, 1997. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of May 5, 1997. ADDRESSES: The service information referenced in this AD may be obtained from AlliedSignal Aerospace, Attn: Data Distribution, M/S 64- 3/2101-201, P.O. Box 29003, Phoenix, AZ 85038-9003; telephone (602) 365-2493, fax (602) 365-5577. This information may be examined at the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. FOR FURTHER INFORMATION CONTACT: Joseph Costa, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone (310) 627-5246; fax (310) 627-5210. SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to AlliedSignal Inc. TFE731 series turbofan engines was published in the Federal Register on July 10, 1996 (61 FR 36310). That action proposed to require removing from service first stage LPT seal plates, Part Number (P/N) 3073552-2 and P/N 3074053-1, prior to accumulating the new, reduced cyclic life limit of 3,700 cycles since new (CSN), and replacement with serviceable parts. The actions would be required to be accomplished in accordance with AlliedSignal Inc. Service Bulletin (SB) No. TFE731-72-3573, dated August 15, 1995. AlliedSignal Inc. SB No. TFE731-72-3001, Service Life Limits of Critical Life Limited Components, Revision 42, dated July 17, 1995, incorporates the new cyclic life limit of 3,700 CSN. Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has added a new paragraph (c) to clarify that operators may seek FAA- approval of modifications to the new life limits only through the alternative method of compliance procedure described in the AD. The FAA has determined that air safety and the public interest require the adoption of the rule with this change.The FAA has determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD. The FAA estimates that 268 engines installed on aircraft of U.S. registry will be affected by this AD, that it will take approximately 1 work hour per engine to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost approximately $5,000 per engine. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $1,356,080. 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. For the reasons discussed above, I certify that this action (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it 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. Sec. 39.13 [AMENDED] 2. Section 39.13 is amended by adding the following new airworthiness directive: 97-04-03 AlliedSignal Inc.: Amendment 39-9926. Docket 96-ANE-08. Applicability: AlliedSignal Inc. Models TFE731-2A, -3C and -3CR series turbofan engines, with first stage low pressure turbine (LPT) seal plates, Part Number (P/N) 3073552-2 and P/N 3074053-1, installed on but not limited to the following aircraft: Cessna Model 650 Citation III and Israel Aircraft Industries Model 1125 Westwind Astra aircraft. Note 1: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless [[Page 10202]] of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been 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 (d) 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 fatigue cracking and subsequent uncontained failure of a first stage LPT seal plate, accomplish the following: (a) Prior to accumulating 3,700 cycles since new (CSN) on LPT seal plates, P/Ns 3073552-2 and 3074053-1, remove from service these first LPT seal plates, and replace with serviceable parts, in accordance with the Accomplishment Instructions of AlliedSignal Inc. Service Bulletin (SB) No. TFE731-72-3573, dated August 15, 1995. (b) This action establishes a new, reduced cyclic life limit of 3,700 CSN for first stage LPT seal plates, P/N 3073552-2 and P/N 3074053-1. (c) Except as provided in paragraph (d) of this AD, no alternative replacement times may be approved for LPT seal plates, P/N 3073552-2 and 3074053-1. (d) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Los Angeles Aircraft Certification Office. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles Aircraft Certification Office. Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Los Angeles Aircraft Certification Office. (e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the aircraft to a location where the requirements of this AD can be accomplished. (f) The actions required by this AD shall be done in accordance with the following AlliedSignal Inc. SB: ------------------------------------------------------------------------ Document No. Pages Date ------------------------------------------------------------------------ TFE731-72-3573..................... 1-6 August 15, 1995 ------------------------------------------------------------------------ Total Pages: 6. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from AlliedSignal Aerospace, Attn: Data Distribution, M/S 64-3/2101-201, P.O. Box 29003, Phoenix, AZ 85038-9003; telephone (602) 365-2493, fax (602) 365-5577. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street NW., suite 700, Washington, DC. (g) This amendment becomes effective on May 5, 1997. Issued in Burlington, Massachusetts, on February 26, 1997. James C. Jones, Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 97-5512 Filed 3-5-97; 8:45 am] BILLING CODE 4910-13-U