[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]
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