AD 97-06-01

AD Final Rules - DRS_97-06-01.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
97-06-01
Document Type:
AD Final Rules
Docket Number:
95-ANE-65
Subject Heading:
Airworthiness Directives; CFM International CFM56-5, -5B, and -5C Series Turbofan Engines
Subject:
High Pressure Compressor Rotor (HPCR) Stage 1-2 Spool
Status:
Current
Citation:
Federal Register: April 04, 1997 (Volume 62, Number 65)
Citation Publish Date:
04/04/1997
Effective Date:
06/03/1997
Make:
CFM International, S.A.
Model:
CFM56-5 | CFM56-5B1 | CFM56-5B1/2P | CFM56-5B1/P | CFM56-5B2 | CFM56-5B2/2P | CFM56-5B2/P | CFM56-5B...Show more
Product Type:
Engine
Product Subtype:
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39 [62 FR 16067 NO. 65 04/04/97]
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 97-06-01
CITATION:   [Federal Register: April 04, 1997 (Volume 62, Number 65)]

PAGE NUMBER:   [Page 16067]

DOCKET NUMBER:   95-ANE-65

AMENDMENT:   39-9958

AD NUMBER:   97-06-01

SUBJECT HEADING:   Airworthiness Directives; CFM International CFM56-5, -5B, and -5C Series Turbofan Engines

ACTION:   Final rule.

SUMMARY:   This amendment adopts a new airworthiness directive (AD), applicable to CFM International CFM56-5, -5B, and -5C series turbofan engines, that requires initial and repetitive borescope inspections of the stage 1 disk bore of certain high pressure compressor rotor (HPCR) stage 1-2 spools for rubs and scratches, and replacement, if found rubbed or scratched, with a serviceable part. This AD also requires removal and replacement of certain stationary number 3 bearing aft air/oil seals as terminating action to the inspection program. This amendment is prompted by a report of an engine found with a rub on the forward corner of the HPCR stage 1 disk bore due to contact with the stationary number 3 bearing aft air/oil seal. The actions specified by this AD are intended to prevent a failure of the stage 1 disk of the HPCR stage 1-2 spool, which could result in an uncontained engine failure and damage to the aircraft.

DATES:   Effective June 3, 1997. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of June 3, 1997.

ADDRESSES:   The service information referenced in this AD may be obtained from CFM
International, Technical Publications Department, One Neumann Way, Cincinnati, OH 45215;
telephone (513) 552-2981, fax (513) 552-2816. 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:   Robert J. Ganley, Aerospace Engineer, Engine
Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park,
Burlington, MA 01803-5299; telephone (617) 238-7138; fax (617) 238-7199.

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 CFM International (CFMI) CFM56-5, -5B, and -5C series turbofan engines was published in the Federal Register on June 4, 1996 (61 FR 28112). That action proposed to require initial and repetitive borescope inspections of the stage 1 disk bore of certain high pressure compressor rotor (HPCR) stage 1-2 spools for rubs and scratches, and replacement, if found rubbed or scratched, with a serviceable part. That action also proposed to require removal and replacement of certain stationary number 3 bearing aft air/oil seals as terminating action to the inspection program.
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.
The commenter supports the rule as proposed.
After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed.
There are approximately 131 engines of the affected design in the worldwide fleet. The manufacturer has advised the FAA that there are no engines installed on U.S. registered aircraft that would be affected by this AD. Therefore, there is no associated cost impact on U.S. operators as a result of this AD. However, should an affected engine be imported on an aircraft and placed on the U.S. registry in the future, it will take approximately 402 work hours to accomplish the required actions, and the average labor rate is $60 per work hour. Required parts will cost approximately $87,700 per engine. Based on these figures, the cost impact of the AD is estimated to be $111,820 per engine.
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. § 39.13 - [AMENDED]
2. Section 39.13 is amended by adding the following new airworthiness directive:

REGULATORY TEXT:   97-06-01 CFM International: Amendment 39-9958. Docket 95-ANE-65.
Applicability: CFM International (CFMI) CFM56-5, -5B, and -5C series turbofan engines, installed on but not limited to Airbus A320, A321, and A340 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 (h) 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 failure of the stage 1 disk of the high pressure compressor rotor (HPCR) stage 1-2 spool, which could result in an uncontained engine failure and damage to the aircraft, accomplish the following:
(a) For CFM56-5, -5B, and -5C engines that have a stationary number 3 bearing aft air/oil seal, Part Number (P/N) 1364M71G02, installed, inspect the stage 1 disk of the HPCR stage 1-2 spool in accordance with the Accomplishment Instructions of CFM56-5 Service Bulletin (SB) No. 72-440, CFM56-5B SB No. 72-064, or CFM56-5C SB No. 72-229, all Revision 2, dated June 23, 1995, as applicable, as follows:
(1) If the disk has not been previously inspected prior to the effective date of this AD, inspect prior to accumulating 2,200 cycles since new (CSN).
(2) If the disk has been previously inspected prior to the effective date of this AD, and the disk was found not to be rubbed or scratched, reinspect prior to accumulating 2,200 cycles since last inspection (CSLI).
(b) Thereafter, for disks that have been inspected in accordance with paragraph (a)(1) or (a)(2) of this AD, inspect in accordance with the Accomplishment Instructions of CFM56-5 SB No. 72-440, CFM56-5B SB No. 72-064, or CFM56-5C SB No. 72-229, all Revision 2, dated June 23, 1995, as applicable, at intervals not to exceed 2,200 CSLI.
(c) Remove from service HPCR stage 1-2 spools with rubbed or scratched stage 1 disks and replace with a serviceable part, as follows:
(1) For spools with less than 2,200 CSN on the effective date of this AD, at the next engine shop visit after the effective date of this AD, or prior to accumulating 2,200 CSN, whichever occurs first.
(2) For spools with 2,200 CSN or more on the effective date of this AD, at the next engine shop visit after the effective date of this AD, or prior to accumulating 2,200 CSLI, whichever occurs first.
(d) Remove from service stationary number 3 aft air/oil seals, P/N 1364M71G02, at the next engine shop visit after the effective date of this AD, and replace with a serviceable part. Compliance with this paragraph constitutes terminating action to the inspection requirements of paragraphs (a)(1), (a)(2), and (b) of this AD.
(e) For the purpose of this AD, a serviceable HPCR stage 1-2 spool is defined as a spool without a rub or scratch indication on the stage 1 disk, a P/N 1834M55G01 spool, or a spool that has accomplished the stage 1 disk rework in accordance with any revision level of CFM56-5 SB No. 72-442, CFM56-5B SB No. 72-066, or CFM56-5C SB No. 72-230, as applicable.
(f) For the purpose of this AD, a serviceable stationary number 3 bearing aft air/oil seal is defined as any seal other than a P/N 1364M71G02 seal.
(g) For the purpose of this AD, an engine shop visit is defined as the induction of an engine into the shop for any reason.
(h) 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 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.
(i) 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.
(j) The actions required by this AD shall be done in accordance with the following CFMI SBs:

Document No	Pages	Revision	Date
CFM56-5 SB No. 72-440	1-9	2	June 23, 1995
Total pages: 9.			
CFM56-5B SB No. 72-064	1-9	2	June 23, 1995
Total pages: 9.			
CFM56-5C SB No. 72-229	1-9	2	June 23, 1995
Total Pages: 9.			

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, One 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 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.
(k) This amendment becomes effective on June 3, 1997.

FOOTER: