99-06-16 CFM International: Amendment 39-11079. Docket 98-ANE-56-AD.
Applicability: CFM International CFM56-5 series turbofan engines installed on, but not limited to, Airbus A319 and A320 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 (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.
Compliance: Required as indicated, unless accomplished previously.
To prevent a low cycle fatigue failure of the high pressure turbine rotor (HPTR) front air seal, which could result in an uncontained engine failure and damage to the aircraft, accomplish the following:
(a) Remove from service CFM International CFM56-5-A1 and -5-A1/F HPTR front air seals, Part Number (P/N) 1319M11P06, 1319M11P07, 1319M11P08, and 1319M11P09, and CFM56-5-A1 HPTR front air seals, P/N 1319M11P05, and replace with a serviceable part, in accordance with CFM56-5 Service Bulletin (SB) No. 72-541, dated July 27, 1998, as follows:
(1) For seals that have accumulated less than 4,000 cycles since new (CSN) on the effective date of this AD, remove the seal from service prior to accumulating 11,000 CSN.
(2) For seals that have accumulated 4,000 CSN or more, but less than 11,000 CSN on the effective date of this AD, accomplish the following:
(i) For engines that have an engine shop visit (ESV) prior to the seal accumulating11,000 CSN, remove the seal from service prior to the seal accumulating 11,000 CSN.
(ii) For engines that do not have an ESV prior to the seal accumulating 11,000 CSN, remove the seal from service prior to the seal accumulating 7,000 cycles in service (CIS) after the effective date of this AD, or prior to the seal accumulating 15,300 CSN, whichever occurs first.
(3) For seals that have accumulated 11,000 CSN or more on the effective date of this AD, remove the seal from service at the next ESV, or prior to the seal accumulating 15,300 CSN, whichever occurs first.
(b) Remove from service CFM International CFM56-5A3 HPTR front air seals, P/N 1319M11P06, 1319M11P07, 1319M11P08, and 1319M11P09, and replace with a serviceable part, in accordance with CFM56-5 SB No. 72-541, dated July 27, 1998, as follows:
(1) For seals that have accumulated less than 3,000 CSN on the effective date of this AD, remove the seal from service prior to accumulating 7,700 CSN.
(2) For seals that have accumulated 3,000 CSN or more, but less than 7,700 CSN on the effective date of this AD, accomplish the following:
(i) For engines that have an ESV prior to the seal accumulating 7,700 CSN, remove the seal from service prior to the seal accumulating 7,700 CSN.
(ii) For engines that do not have an ESV prior to the seal accumulating 7,700 CSN after the effective date of the AD, remove the seal from service prior to the seal accumulating 4,700 CIS after the effective date of this AD, or prior to the seal accumulating 13,000 CSN, whichever occurs first.
(3) For seals that have accumulated 7,700 CSN or more on the effective date of this AD, remove the seal from service at the next ESV, or prior to the seal accumulating 13,000 CSN, whichever occurs first.
(c) For CFM56-5A4, -5A4/F, -5A5, and -5A5/F HPTR front air seals, P/N 1319M11P05, 1319M11P06, 1319M11P07, 1319M11P08, and 1319M11P09, that have previously operated in CFM56-5-A1, -5-A1/F, or -5A3 engine models, recalculate the HPTR front air seal total cycles remaining using 11,000 cycles for the CFM56-5-A1 and CFM56-5-A1/F engine models, and 7,700 cycles for the CFM56-5A3 engine model, in accordance with CFM56-5 SB No. 72-541, dated July 27, 1998, within 750 CIS after the effective date of this AD.
Note 2: The current HPTR front air seal retirement life for the CFM56-5A4, -5A4/F, -5A5, and -5A5/F engine models is 9,100 cycles, and is not affected by this AD.
Note 3: For additional information on recalculating the HPTR front air seal total cycles remaining see Chapter 05, Section 05-11-00, of the CFM56-5 series Engine Shop Manual, CFMI-TP.SM.7.
(d) This AD establishes new LCF retirement lives of 11,000 cycles for CFM56-5-A1 and -5-A1/F HPTR front air seals, and 7,700 cycles for CFM56-5A3 HPTR front air seals, which is published in Chapter 05, Section 05-11-03, of the CFM56-5 series Engine Shop Manual, CFMI-TP.SM.7. The following conditions also apply:
(1) Except as provided inparagraph (g) of this AD, no alternative retirement lives may be approved for the CFM56-5-A1, -5-A1/F, and -5A3 HPTR front air seals.
(2) After the effective date of this AD, no CFM56-5-A1 and -5-A1/F HPTR front air seals may be installed or reinstalled on an engine if the seals have accumulated more than 11,000 CSN.
(3) After the effective date of this AD, no CFM56-5A3 HPTR front air seals may be installed or reinstalled on an engine if the seals have accumulated more than 7,700 CSN.
(e) For the purpose of this AD, an "engine shop visit" is defined as the induction of an engine into the shop for maintenance involving the separation of any major mating engine flanges, or the removal of a disk or spool, except that the separation of engine flanges solely for the purposes of transportation without subsequent engine maintenance does not constitute an engine shop visit.
(f) For the purpose of this AD, a "serviceable part" is defined as one that has not exceeded its respectivenew retirement life as set out in this AD.
(g) 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. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Engine Certification Office.
Note 4: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Engine Certification Office.
(h) 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.
(i) The actions required by this AD shall be done in accordance with the following CFM International SB:
Document No
Pages
DateCFM56-5 SB No. 72-541
1-8
July 27, 1998
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 may be obtained from CFM International, Technical Publications Department, 1 Neumann Way, Cincinnati, OH 45215; telephone (513) 552-2981, fax (513) 552-2816. 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.
(j) This amendment becomes effective on April 21, 1999.