[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:

------------------------------------------------------------------------
              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