94-07-05 GENERAL ELECTRIC COMPANY: Amendment 39-8863. Docket No. 94-ANE-03. This amendment supersedes priority letter AD 93-10-09.
Applicability: General Electric Company (GE) CT58-110 and -140 series turboshaft engines installed on but not limited to Boeing Vertol 107 series, and Sikorsky S61 and S62 series aircraft.
Compliance: Required as indicated, unless accomplished previously.
To prevent an uncontained engine failure and damage to the aircraft, accomplish the following:
(a) For stage 1 turbine wheels, Part Number (P/N) 4002T17P01 and 4002T17P02, and stage 2 turbine wheels, P/N 4002T96P01 and 4002T96P02, that have not previously accomplished GE CT58 Service Bulletin (SB) No. A72-126 (CEB-206), Revision 1, dated December 5, 1969, inspect the wheels in accordance with paragraphs 2.A or 2.B; and 2.D, 2.E, and 2.F of GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993, as follows, or remove the wheels from service prior to August 1, 1994, andreplace with a serviceable part, whichever occurs earlier:
(1) For wheels utilized in repetitive heavy lift (RHL) or external lift operation:
(i) For wheels that have accumulated less than 500 hours time since new (TSN) on the effective date of this airworthiness directive (AD), inspect the wheels prior to accumulating 900 hours TSN.
(ii) For wheels that have accumulated 500 hours TSN or more on the effective date of this AD, inspect the wheels at the next engine shop visit, or prior to accumulating 400 hours time in service (TIS) after the effective date of this AD, whichever occurs earlier.
(2) For wheels utilized in non-RHL operation:
(i) For wheels that have accumulated less than 1,500 hours TSN on the effective date of this AD, inspect the wheels prior to accumulating 2,000 hours TSN.
(ii) For wheels that have accumulated 1,500 hours TSN or more on the effective date of this AD, inspect the wheels at the next engine shop visit, or prior toaccumulating 600 hours TIS after the effective date of this AD, whichever occurs earlier.
(b) For stage 1 turbine wheel, P/N 4002T17P04, and stage 2 turbine wheel, P/N 4002T96P04, inspect the wheels in accordance with paragraphs 2.D and 2.E of GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993, and the inspection schedule outlined in paragraph (a)(1) and (a)(2) of this AD, as applicable, or remove the wheels from service prior to August 1, 1994, and replace with a serviceable part, whichever occurs earlier.
(c) For wheels inspected in accordance with paragraph (a) of this AD, accomplish the following:
(1) Prior to further flight, remove from service cracked wheels, wheels that do not meet the required web thickness limits, or wheels that have a cooling plate locating groove or channel (rabbet groove) radius less than 0.006 inches, and replace with a serviceable part.
(2) Prior to further flight, mark wheels that have a rabbet groove radius of 0.006 inches or greater, by marking the part with the number "CEB 206, REV 2" in accordance with paragraph 2.H of GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993.
(d) For wheels inspected in accordance with paragraph (b) of this AD, accomplish the following:
(1) Prior to further flight, remove from service cracked wheels, and replace with a serviceable part.
(2) Prior to further flight, mark wheels with the number "CEB 206, REV 2" in accordance with paragraph 2.H of GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993.
(e) For stage 1 turbine wheels, P/N 4002T17P02 and 4002T17P04, and stage 2 turbine wheels, P/N 4002T96P02 and 4002T96P04, that have previously accomplished GE CT58 SB No. A72-126 (CEB-206), Revision 1, dated December 5, 1969, eddy current inspect (ECI) and fluorescent penetrant inspect (FPI) the wheels in accordance with GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993, as follows, or remove the wheels from service and replace with a serviceable part in accordance with paragraph (g)(1) or (g)(2) of this AD, as applicable, whichever occurs earlier:
(1) For wheels utilized in RHL or external lift operation, inspect wheels in accordance with the inspection limits defined in Table 1 of GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993, or prior to 400 hours TIS after the effective date of this AD, whichever occurs later.
(2) For wheels utilized in non-RHL operation, inspect wheels in accordance with the inspection limits defined in Table 1 of GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993, or prior to 600 hours TIS after the effective date of this AD, whichever occurs later.
(f) For wheels inspected in accordance with paragraph (e) of this AD, accomplish the following:
(1) Prior to further flight, remove from service cracked wheels, and replace with a serviceable part.
(2) Prior to further flight, mark wheels with thenumber "CEB 206, REV 2" in accordance with paragraph 2.H of GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993.
(g) For wheels marked in accordance with paragraph (c)(2), (d)(2), or (f)(2) of this AD:
(1) For wheels that have a rabbet groove radius less than 0.013 inches, remove from service prior to August 1, 1994, and replace with a serviceable part.
(2) For wheels that have a rabbet groove radius of 0.013 inches or greater, remove from service in accordance with the inspection limits defined in Table 1 of GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993, or prior to August 1, 1994, whichever occurs later, and replace with a serviceable part.
(3) ECI and FPI wheels in accordance with GE CT58 SB No. A72-126 (CEB-206), Revision 2, dated August 31, 1993, as follows:
(i) For wheels utilized in RHL or external lift operation, reinspect wheels at intervals not to exceed 1,000 hours TIS since the last inspection.
(ii)For wheels utilized in non-RHL operation, reinspect wheels at intervals not to exceed 2,000 hours TIS since the last inspection.
(iii) Prior to further flight, remove from service cracked wheels, and replace with a serviceable part.
(h) Remove from service within 400 hours TIS after the effective date of this AD, stage 1 turbine wheels, P/N 278D978P002, 37D400498P101, 37D400307P101, 37D400010P101, 37D400227P101, 3018T97P02, 3018T97P03, and 3018T97P04; and stage 2 turbine wheels, P/N 278D979P002, 37D400499P101, 37D400228P102, 37D400004P102, 3018T98P01, 3018T98P02, 3018T98P03, and 3018T98P04, and replace with serviceable parts.
(i) For the purpose of this AD, the following definitions apply:
(1) An engine shop visit is defined as the induction of an engine into a shop for maintenance involving the separation of any major flange.
(2) RHL operation is defined as more than ten lift-carry-drop cycles per hour TIS without landing, or more than ten takeoffs and landings per hour TIS.
(3) External lift operation is defined as up to ten lift-carry-drop cycles per hour TIS without landing, or up to ten takeoffs and landings per hour TIS.
(4) Non-RHL operation is defined as carrying passengers or internal cargo.
(5) A serviceable part is defined as stage 1 turbine wheel, P/N 4002T17P02 TF3, and stage 2 turbine wheel, P/N 4002T96P02 TF3.
(j) 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 should be forwarded through an appropriate FAA Principal 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.
(k) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the aircraft to a location where the requirements of this AD can be accomplished.
(l) The inspection and replacement shall be done in accordance with the following service bulletin:
DOCUMENT NO.
PAGE
REVISION
DATE
GE CT58 SB No. A72-126 (CEB-206)
1-28
2
August 31, 1993
Total Pages: 28.
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, 1000 Western Ave., Lynn, MA 01910. 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.
(m) This amendment supersedes priority letter AD 93-10-09, issued May 20, 1993.
(n) This amendment becomes effective on April 19, 1994.