97-21-08: Stage 1 forward cooling plate

97-21-08 General Electric Company: Amendment 39-10161. Docket 97-ANE-18-AD. Applicability: General Electric Company (GE) Models CT58-110-1, -110-2, -140-1, and -140-2, and T58-GE-3/-5/-8F/-10/-100 series turboshaft engines, with stage 1 forward cooling plate, Part Number (P/N) 37C300055P101, stage 2 forward cooling plate, P/N 3000T88P02, and stage 2 aft cooling plate, P/N 3002T27P01, installed. These engines are installed on but not limited to Boeing Vertol 107 series, and Sikorsky S61 and S62 series aircraft. 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(c) 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 cooling plate fracture, which could result in a contained engine failure and an inflight engine shutdown, accomplish the following: (a) Remove from service affected cooling plates, listed by serial number in GE Aircraft Engines CT58 Service Bulletin (SB) No. 72-188 (CEB-293), Revision 1, dated July 15, 1997, and replace with serviceable parts, at the next part exposure, or next light overhaul, whichever occurs first, but not to exceed 1,000 hours time in service (TIS) for engines installed on aircraft that have engaged in Repetitive Heavy Lift (RHL) operations, or 2,000 hours TIS for engines installed on aircraft that have never engaged in RHL operations, in accordance with that SB. (b) For the purpose of this AD, the following definitions apply: (1) RHL operation is defined as performing more than 10 lift-carry-drop cycles per hour TIS without landing, or more than 10 takeoffs and landings per hour TIS. (2) Light overhaul is defined as scheduled engine maintenance that allows the engine to continue in service until scheduled major overhaul time is reached. (c) 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, Engine Certification Office. The request shall be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Engine 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 Engine Certification Office. (d) 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. (e) The actions required by this AD shall be done in accordance with the following GE Aircraft Engines SB: Document No Pages Revision Date 72-188 (CEB-293) 1-7 1 July 15, 1997 Total Pages: 7. 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 General Electric Company (GE), 1000 Western Ave., Lynn, MA 01909; telephone (781) 594-9894, fax (781) 594-1527. 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. (f) This amendment becomes effective on December 19, 1997.