[Federal Register Volume 61, Number 198 (Thursday, October 10, 1996)]
[Rules and Regulations]
[Pages 53038-53040]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-25167]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-ANE-15; Amendment 39-9742; AD 96-18-16]
RIN 2120-AA64


Airworthiness Directives; CFM International CFM56-2/-2A/-2B/-3/-
3B/-3C/-5 Series Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to CFM International (CFMI) CFM56-2/-2A/-2B/-3/-3B/-3C/-5 
series turbofan engines, that requires part number reidentification of 
certain low pressure turbine rotor (LPTR) stub shafts and conical 
supports, and reduction of the low cycle fatigue (LCF) retirement lives 
for these reidentified parts. This amendment is prompted by the results 
of a refined life analysis performed by the manufacturer which revealed 
minimum calculated LCF lives significantly lower than published LCF 
retirement lives. The actions specified by this AD are intended to 
prevent an LCF failure of the LPTR stub shaft and conical support, 
which could result in an uncontained engine failure and damage to the 
aircraft.

DATES: Effective December 9, 1996.
    The incorporation by reference of certain publications listed in 
the

[[Page 53039]]

regulations is approved by the Director of the Federal Register as of 
December 9, 1996.

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: Glorianne Messemer, Aerospace 
Engineer, Engine Certification Office, FAA, Engine and Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; 
telephone (617) 238-7132; 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) CFM56-2/-
2A/-2B/-3/-3B/-3C/-5 series turbofan engines was published in the 
Federal Register on September 1, 1995 (60 FR 45683). That action 
proposed to require part number reidentification of certain low 
pressure turbine rotor (LPTR) stub shafts and conical supports, and 
reduction of the low cycle fatigue (LCF) retirement lives for these 
reidentified parts in accordance with the following CFMI service 
bulletins (SB's): CFM56-2 SB No. 72-728, Revision 2, dated December 21, 
1994, CFM56-2A SB No. 72-338, dated November 25, 1993, CFM56-2B SB No. 
72-476, dated December 7, 1993, and CFM56-3/-3B/-3C SB No. 72-695, 
dated November 25, 1993.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    Two commenters support the rule as proposed.
    One commenter states that CFM56-3 series engines should be included 
in compliance paragraph (f) of the proposed rule. The FAA concurs, and 
paragraph (f) of this final rule has been revised accordingly.
    One commenter suggests that the proposed rule be revised to address 
the LCF retirement lives of CFM56-3B and CFM56-3C series engines that 
are operated at reduced thrust ratings, since the lives are dependent 
on the thrust rating. The FAA concurs. Paragraphs (f) and (g) of this 
final rule have been revised, and paragraph (j) has been added 
accordingly.
    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 with the changes described 
previously. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    The FAA estimates that 41 engines installed on aircraft of U.S. 
registry will be affected by this AD, that it will take approximately 
0.25 work hours per engine to accomplish the required actions, and that 
the average labor rate is $60 per work hour. Assuming that the parts 
cost is proportional to the reduction of the LCF retirement lives, the 
required parts will cost approximately $6,687 per engine. Based on 
these figures, the total cost impact of the AD on U.S. operators is 
estimated to be $274,782.
    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 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

96-18-16  CFM International: Amendment 39-9742. Docket 95-ANE-15.

    Applicability: CFM International (CFMI) CFM56-2/-2A/-2B/-3/-3B/-
3C/-5 series turbofan engines installed on, but not limited to 
Airbus A319 and A320 series, McDonnell Douglas DC-8 series, and 
Boeing 737, as well as Boeing E-3, E-6, and KC-135 (military) series 
aircraft.

    Note: 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 (k) 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 (LCF) failure of the low pressure 
turbine rotor (LPTR) stub shaft and conical support, which could 
result in an uncontained engine failure and damage to the aircraft, 
accomplish the following:
    (a) Reidentify CFM56-2A LPTR stub shafts, Part Numbers (P/N) 
301-330-623-0 and 301-330-624-0, with Serial Numbers (S/N) listed in 
Table 2 of CFMI CFM56-2A Service Bulletin (SB) No. 72-338, dated 
November 25, 1993, in accordance with the Accomplishment 
Instructions of CFMI CFM56-2A SB No. 72-338, dated November 25, 
1993, at the next piece-part exposure after the effective date of 
this AD, but not to exceed 6,400 cycles since new (CSN).
    (b) Reidentify CFM56-2B LPTR stub shafts, P/N 301-330-618-0, 
301-330-619-0, 301-330-623-0, and 301-330-624-0, with S/N listed in 
Table 2 of CFMI CFM56-2B SB No. 72-476, dated December 7, 1993, in 
accordance with the Accomplishment Instructions of CFMI CFM56-2B SB 
No. 72-476, dated December 7, 1993, at the next piece-part exposure 
after the effective date of this AD, but not to exceed 8,300 CSN.
    (c) Reidentify CFM56-2 LPTR conical supports, P/N 305-056-106-0, 
305-056-109-0, 305-056-110-0, and 305-056-111-0, with S/N listed in 
Table 1 of CFMI CFM56-2 SB No. 72-728, Revision 2, dated December 
21, 1994, in accordance with the Accomplishment Instructions of CFMI 
CFM56-2 SB No. 72-728, Revision 2, dated

[[Page 53040]]

December 21, 1994, at the next piece-part exposure after the 
effective date of this AD, but not to exceed 18,000 CSN.
    (d) Reidentify CFM56-2A LPTR conical supports, P/N 305-056-110-0 
and 305-056-111-0, with S/N listed in Table 1 of CFMI CFM56-2A SB 
No. 72-338, dated November 25, 1993, in accordance with the 
Accomplishment Instructions of CFMI CFM56-2A SB No. 72-338, dated 
November 25, 1993, at the next piece-part exposure after the 
effective date of this AD, but not to exceed 5,700 CSN.
    (e) Reidentify CFM56-2B LPTR conical supports, P/N 305-056-106-
0, 305-056-109-0, 305-056-110-0, and 305-056-111-0, with S/N listed 
in Table 1 of CFMI CFM56-2B SB No. 72-476, dated December 7, 1993, 
in accordance with the Accomplishment Instructions of CFMI CFM56-2B 
SB No. 72-476, dated December 7, 1993, at the next piece-part 
exposure after the effective date of this AD, but not to exceed 
8,700 CSN.
    (f) Reidentify CFM56-3/-3B/-3C LPTR stub shafts, P/N 301-330-
618-0, 301-330-619-0, 301-330-623-0, and 301-330-624-0, with S/N 
listed in Table 2 of CFMI CFM56-3/-3B/-3C SB No. 72-695, dated 
November 25, 1993, in accordance with the Accomplishment 
Instructions of CFMI CFM56-3/-3B/-3C SB No. 72-695, dated November 
25, 1993, as follows:
    (1) For CFM56-3/-3B/-3C series engines operating at the Category 
A thrust rating, at the next piece-part exposure after the effective 
date of this AD, but not to exceed a total Category A thrust rating 
life of 20,000 CSN.
    (2) For CFM56-3B/-3C series engines operating at the Category B 
thrust rating, at the next piece-part exposure after the effective 
date of this AD, but not to exceed a total Category B thrust rating 
life of 11,400 CSN.
    (3) For CFM56-3C series engines operating at the Category C 
thrust rating, at the next piece-part exposure after the effective 
date of this AD, but not to exceed a total Category C thrust rating 
life of 7,900 CSN.
    (g) Reidentify CFM56-3/-3B/-3C LPTR conical supports, P/N 305-
056-106-0, 305-056-109-0, 305-056-110-0, and 305-056-111-0, with S/N 
listed in Table 1 of CFMI CFM56-3/-3B/-3C SB No. 72-695, dated 
November 25, 1993, in accordance with the Accomplishment 
Instructions of CFMI CFM56-3/-3B/-3C SB No. 72-695, dated November 
25, 1993, as follows:
    (1) For CFM56-3/-3B/-3C series engines operating at the Category 
A thrust rating, at the next piece-part exposure after the effective 
date of this AD, but not to exceed a total Category A thrust rating 
life of 12,100 CSN.
    (2) For CFM56-3B/-3C series engines operating at the Category B 
thrust rating, at the next piece-part exposure after the effective 
date of this AD, but not to exceed a total Category B thrust rating 
life of 9,300 CSN.
    (3) For CFM56-3C series engines operating at the Category C 
thrust rating, at the next piece-part exposure after the effective 
date of this AD, but not to exceed a total Category C thrust rating 
life of 5,700 CSN.
    (h) Remove from service CFM56-5 LPTR conical support, P/N 336-
000-305-0, prior to accumulating 11,300 CSN.
    (i) This action establishes new LCF retirement lives for parts 
reidentified in accordance with paragraphs (a) through (g) of this 
AD, and the new LCF retirement life noted in paragraph (h) of this 
AD, which are published in Chapter 05 of the applicable engine shop 
manual (CFM56-2 CFMI-TP.SM.4, CFM56-2A/-2B CFMI-TP.SM.6, CFM56-3 
CFMI-TP.SM.5, and CFM56-5 CFMI-TP.SM.7).
    (j) The Category A, B, and C thrust rating noted in paragraphs 
(f) and (g) of this AD are defined in Chapter 05 of CFM56-3 engine 
shop manual, CFMI-TP.SM.5.
    (k) 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.

    (l) 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.
    (m) The actions required by this AD shall be done in accordance 
with the following CFMI SB's:

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             Document No.                  Pages                Revision                        Date            
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CFM56-2 SB No. 72-728................           1    2............................  Dec. 21, 1994.              
                                              2-7    Original.....................  Nov. 25, 1993.              
                                                8    2............................  Dec. 21, 1994.              
                                                9    Original.....................  Nov. 25, 1993.              
    Total Pages: 9.                                                                                             
CFM56-2A SB No. 72-338...............         1-8    Original.....................  Nov. 25, 1993.              
    Total Pages: 8.                                                                                             
CFM56-2B SB No. 72-476...............         1-9    Original.....................  Dec. 7, 1993.               
    Total Pages: 9.                                                                                             
CFM56-3/-3B/-3C SB No. 72-695........         1-9    Original.....................  Nov. 25, 1993.              
    Total Pages: 9.                                                                                             
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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.
    (n) This amendment becomes effective on December 9, 1996.

    Issued in Burlington, Massachusetts, on September 19, 1996.
James C. Jones,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 96-25167 Filed 10-9-96; 8:45 am]
BILLING CODE 4910-13-U