[Federal Register Volume 60, Number 174 (Friday, September 8, 1995)]
[Rules and Regulations]
[Pages 46760-46761]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-20850]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-ANE-41; Amendment 39-9347; AD 95-17-16]
Airworthiness Directives; General Electric Company CF6 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 General Electric Company (GE) CF6-80A series turbofan
engines, that requires an initial and repetitive on-wing eddy current
inspection or an on-wing spot fluorescent penetrant inspection of the
compressor rear frame (CRF) midflange for cracks, and replacement, if
necessary, with serviceable parts. This amendment also requires removal
from service of certain CRF's as a terminating action to the on-wing
inspection program. This amendment is prompted by a report of a CRF
separation that resulted in a rejected takeoff. The actions specified
by this AD are intended to prevent a CRF separation, which could result
in a rejected takeoff and damage to the aircraft.
DATES: Effective November 7, 1995.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of November 7, 1995.
ADDRESSES: The service information referenced in this AD may be
obtained from General Electric Aircraft Engines, CF6 Distribution
Clerk, Room 132, 111 Merchant Street, Cincinnati, OH 45246. 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: Richard Woldan, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803-5299; telephone (617)
238-7136; 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 General Electric Company (GE) CF6-
80A series turbofan engines was published in the Federal Register on
February 22, 1995 (60 FR 9792). That action proposed to require an
initial and repetitive on-wing eddy current inspection or on- wing spot
fluorescent penetrant inspection of the compressor rear frame (CRF)
midflange for cracks, and replacement, if necessary, with serviceable
parts. This action also proposed to require removal from service of
non-modified CRF's as a terminating action to the on-wing inspection
program. The actions would be required to be accomplished in accordance
with GE CF6-80A Service Bulletin (SB) No. 72-593, Revision 2, dated
March 19, 1992.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Three commenters request that the FAA move the compliance end date
ahead one year to December 31, 1997. One commenter based that request
on that commenter's planned acquisition of some affected engines that
have not undergone the required modifications. The FAA does not concur.
The commenters all recognize and accept the FAA's determination that AD
action is necessary. The stated reasons for the requested extension in
complying with the AD is the added cost of non-scheduled engine
removals to perform the required modifications, and since the on-wing
inspections have been successful in detecting cracks to date. The FAA
has already considered the fleet-wide costs to operators in complying
with this AD. In the normal course of that analysis, the FAA has
determined that December 31, 1996, fairly and reasonably balances the
safety need to eliminate this unsafe condition from the fleet as
quickly as possible with operators' needs to avoid unscheduled
maintenance actions. Individual operators who believe their
circumstances warrant relief from this compliance schedule may submit
requests for alternative methods of compliance or adjustments to the
compliance times.
One commenter requests that the FAA broaden its economic analysis
to include items beyond direct labor and parts costs to accomplish the
required actions of the AD, such as maintenance scheduling costs. The
FAA does not concur. In making a finding that an unsafe condition
exists, the FAA has determined that the level of safety attained by the
approved type design is no longer achieved, and the required actions
are necessary to restore that level of safety. Because the type design
must maintain that level of safety, necessary actions to restore that
level of safety do not add additional regulatory requirements, and do
not require a full cost-benefit analysis. The cost analysis is
therefore limited to the direct costs of performing the required
actions to restore the type design to that level of safety. When
establishing compliance times, however, the FAA does try to strike a
balance between the need to restore the type design to its certified
level of safety with operators' need to avoid unscheduled maintenance
actions.
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.
The FAA estimates that 81 engines installed on aircraft of U.S.
registry will be affected by this AD, that it will take approximately
85 work hours per engine to accomplish the required actions, and that
the average labor rate is $60 per work hour. Required parts will cost
approximately $20,644 per engine. Based on these figures, the total
cost impact of the AD on U.S. operators is estimated to be $2,085,264.
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
[[Page 46761]]
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), 40101, 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
95-17-16 General Electric Company: Amendment 39-9347. Docket 94-ANE-
41.
Applicability: General Electric Company (GE) CF6-80A series
turbofan engines installed on, but not limited to, Airbus A310
series and Boeing 767 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 use the
authority provided in paragraph (d) to request approval from the
Federal Aviation Administration (FAA). This approval may address
either no action, if the current configuration eliminates the unsafe
condition, or different actions necessary to address the unsafe
condition described in this AD. Such a request should include an
assessment of the effect of the changed configuration on the unsafe
condition addressed by this AD. In no case does the presence of any
modification, alteration, or repair remove any engine from the
applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent a compressor rear frame (CRF) separation, which could
result in a rejected takeoff and damage to the aircraft, accomplish
the following:
(a) Inspect CRF, Part Numbers (P/N) 9283M77G07, 9283M77G08,
9283M77G09, 9283M77G11, 9283M77G14, 7283M77G15, 9283M77G16,
9283M77G17, 9283M77G18, 9283M77G19, 1338M77G01, 1338M77G02,
1338M77G03, 1338M77G04, 1338M77G05, and 1338M77G06, that have not
accomplished the midflange rework or replacement in accordance with
any revision level of GE CF6-80A Service Bulletin (SB) No. 72-600 or
72-611, prior to the effective date of this AD, as follows:
(1) Perform an on-wing eddy current inspection (ECI) or an on-
wing spot fluorescent penetrant inspection (FPI) of the CRF
midflange for cracks in accordance with the Accomplishment
Instructions and the schedule outlined in Table 1 of GE CF6-80A SB
No. 72-593, Revision 2, dated March 19, 1992, or within 1,000 cycles
in service since the last shop level FPI, whichever occurs later,
after the effective date of this AD.
(2) Thereafter, reinspect the CRF midflange for cracks in
accordance with the Accomplishment Instructions and schedule
outlined in Table 2 of GE CF6-80A SB No. 72-593, Revision 2, dated
March 19, 1992.
(3) Remove from service prior to further flight CRF's with
cracked midflanges that exceed the on-wing serviceable limits
specified in Table 2 of GE CF6-80A SB No. 72-593, Revision 2, dated
March 19, 1992, and replace with a serviceable part.
(b) Remove from service CRF's identified in paragraph (a) of
this AD at the next piece-part exposure, or by December 31, 1996,
whichever occurs earlier, and replace with a serviceable part.
Removal and replacement of CRF's in accordance with this paragraph
constitutes terminating action to the on-wing inspection
requirements of paragraph (a) of this AD.
(c) For the purpose of this AD, a serviceable part is defined as
a CRF that has accomplished the midflange rework or replacement in
accordance with any revision level of GE CF6-80A SB No. 72-600 or
72-611.
(d) 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.
(e) 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.
(f) The actions required by this AD shall be done in accordance
with the following SB:
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Document No. Pages Revision Date
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GE CF6-80A SB No. 72-593............... 1-4 2 Mar. 19,
1992.
5-8 1 Oct. 30,
1991.
9 2 Mar. 19,
1992.
10-12 1 Oct. 30,
1991.
13-15 2 Mar. 19,
1992.
16-22 1 Oct. 30,
1991.
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Total Pages: 22.
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 Aircraft
Engines, CF6 Distribution Clerk, Room 132, 111 Merchant Street,
Cincinnati, OH 45246. 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.
(g) This amendment becomes effective on November 7, 1995.
Issued in Burlington, Massachusetts, on August 15, 1995.
James C. Jones,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 95-20850 Filed 9-7-95; 8:45 am]
BILLING CODE 4910-13-U
