AD 98-04-15 Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines

Models named: TPE331-1, -2, -2UA, -3U, - 3UW, -5, -5A, -5AB, -5B, -6. Read the applicability below — it usually turns on serial or part numbers too.

AlliedSignal Inc., (formerly Garrett Engine Division, Garrett Turbine Engine Company and AiResearch Manufacturing Company of Arizona) Model TPE331-1, -2, -2UA, -3U, - 3UW, -5, -5A, -5AB, -5B, -6, and -6A turboprop and TSE331-3U turboshaft engines with third stage turbine stators, Part Number (P/ N) 868379-3, except those engines with turbine stators listed by Serial Number (S/N) in Table 1 of the National Flight Services Alert Service Bulletin (ASB) No. NF-TPE331-A72-10961, dated April 28, 1997. These engines are installed on but not limited to: Mitsubishi MU-2B series (MU-2 series); Construcciones Aeronauticas, S.A. (CASA) C-212 series; Fairchild SA226 series (Swearingen Merlin and Metro series); Prop-Jets, Inc. Model 400; Twin Commander 680 and 690 (Jetprop Commander); Rockwell Commander S-2R; Shorts Brothers and Harland, Ltd. SC7 (Skyvan); Dornier 228 series; Beech 18 and 45 series and Models JRB-6, 3N, 3NM, 3TM, and B100; Pilatus PC-6 series (Fairchild Porter and Peacemaker); De Havilland DH 104 series 7AXC (Dove); Ayres S-2R series; Grumman American G-164 series; and Schweizer G-164 series airplanes; and Sikorsky S-55 series (Helitec Corp. S55T) helicopters. Note 1: 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 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 (g) 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.

Required as indicated, unless accomplished previously. To prevent third stage turbine wheel separation due to fatigue cracking and shifting of the third stage turbine stator, which could result in an uncontained engine failure and damage to the aircraft, accomplish the following: (a) For engines with third stage turbine stators with S/Ns listed in Table 1 of National Flight Services ASB No. NF-TPE331-A72- 10961, dated April 28, 1997, no action is required. (b) For engines with third stage turbine stators with S/Ns not listed in Table 1 of National Flight Services ASB No. NF-TPE331-A72- 10961, dated April 28, 1997, remove the unserviceable third stage turbine stator assembly in accordance with the applicable engine maintenance manual and the following schedule: ------------------------------------------------------------------------ Third stage turbine stator cycles in service (CIS) since radiographic inspection in accordance with AD 87-19-02 Removal schedule paragraph (b) or AD 93-05-09 paragraph (h) ------------------------------------------------------------------------ Unknown CIS since inspection. Remove within 600 CIS after the effective date of this AD, at next access, or prior to March 31, 2002, whichever occurs first. 2200 or more CIS since Remove within 600 CIS after the effective inspection. date of this AD, at next access, or prior to March 31, 2002, whichever occurs first. Less than 2200 CIS since Remove prior to accumulating 2,800 CIS, inspection. at next access, or prior to March 31, 2002, whichever occurs first. ------------------------------------------------------------------------ (c) For the purpose of this AD, the next access to the third stage stator assembly is defined as disassembly of the turbine beyond the removal of the third stage rotor. Note 2: This AD does not supersede AD 93-05-09. The removal schedule in paragraph (b) of this AD does not affect the requirements of AD 93-05-09. (d) For the purpose of determining third stage turbine stator removal under paragraph (b) of this AD, third stage turbine stator hours time in service (TIS) may be converted to CIS since inspection by multiplying by 1.5 the number of hours since radiographic inspection in accordance with paragraph (b) of AD 87-19-02 or paragraph (h) of AD 93-05-09. (e) For third stage turbine stator assemblies removed in accordance with paragraph (b) of this AD, accomplish either a radiographic inspection for inadequate weld penetration and fatigue cracking, and, if necessary, replace with a serviceable assembly in accordance with the Accomplishment Instructions of National Flight Services ASB No. NF-TPE331-A72-10961, dated April 28, 1997; or replace with a serviceable assembly in accordance with the Accomplishment Instructions of AlliedSignal Inc. ASB No. TPE331-A72- 0861, Revision 2, dated April 23, 1997. Accomplishing the radiographic inspection required by this paragraph constitutes compliance with the radiographic inspection requirement of paragraph (h) of AD 93-05-09. (f) 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. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles Aircraft Certification Office. Note 3: 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. (g) 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. (h) The actions required by this AD shall be done in accordance with the following ASBs: ---------------------------------------------------------------------------------------------------------------- Document No. Pages Revision Date ---------------------------------------------------------------------------------------------------------------- National Flight Services ASB No. NF- 1-11 Original......................... Apr. 28, 1997. TPE331-A72-10961. Total Pages: 11. AlliedSignal Inc. ASB No. TPE331- 1 2................................ Apr. 23, 1997. A72-0861. 2 1................................ Oct. 25, 1996. [[Page 9734]] 3-5 2................................ Apr. 23, 1997. 6 1................................ Oct. 25, 1996. 7 2................................ Apr. 23, 1997. 8 1................................ Oct. 24, 1996. Total Pages: 8. ---------------------------------------------------------------------------------------------------------------- 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 of AlliedSignal Alert Service Bulletin No. TPE331-A72- 0861, Revision 2, dated April 23, 1997, 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 of National Flight Services ASB No. NF- TPE331-A72-10961, dated April 28, 1997, may be obtained from either National Flight Services, Inc. 10971 E. Airport Services Road, Toledo Express Airport, Swanton, OH 43558; telephone (419) 865-2311, fax (419) 867-4224, or http://www.natfs.com , or National Flight Services of Arizona, Inc., 5170 W. Bethany Home Road, Glendale, AZ 85301; telephone (602) 931-1143, fax (602) 931-7264. Copies may be inspected at the FAA, New England Region, Office of the Regional 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. (i) This amendment becomes effective on April 27, 1998. Issued in Burlington, Massachusetts, on February 6, 1998. James C. Jones, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 98-3798 Filed 2-25-98; 8:45 am] BILLING CODE 4910-13-P