[Federal Register: October 27, 2004 (Volume 69, Number 207)]
[Rules and Regulations]
[Page 62571-62574]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27oc04-7]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-NE-43-AD; Amendment 39-13835; AD 2004-22-07]
RIN 2120-AA64
Airworthiness Directives; General Electric Company (GE) CF6-80C2
Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for GE
CF6-80C2 turbofan engines with certain part number (P/N) high pressure
turbine stage 2 nozzle guide vanes (HPT S2 NGVs) installed. This AD
requires flex borescope inspections of HPT S2 NGVs installed in CF6-
80C2 turbofan engines. This AD results from an uncontained engine
failure due to HPT S2 NGV distress. We are issuing this AD to prevent
blade separation from HPT S2 NGV distress, which could result in an
uncontained engine failure.
DATES: This AD becomes effective December 1, 2004. The Director of the
Federal Register approved the incorporation by reference of certain
publications listed in the regulations as of December 1, 2004.
ADDRESSES: You can get the service information identified in this AD
from General Electric Company via Lockheed Martin Technology Services,
10525 Chester Road, suite C, Cincinnati, Ohio 45215, telephone (513)
672-8400; fax (513) 672-8422.
You may examine the AD docket at the FAA, New England Region,
Office of the Regional Counsel, 12 New England Executive Park,
Burlington, MA. You may examine the service information, at the FAA,
New England Region, Office of the Regional Counsel, 12 New England
Executive Park, Burlington, MA; or at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html
.
[[Page 62572]]
FOR FURTHER INFORMATION CONTACT: Eugene Triozzi, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA; telephone (781) 238-7148;
fax (781) 238-7199.
SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39
with a proposed AD. The proposed AD applies to GE CF6-80C2 turbofan
engines with certain P/N HPT S2 NGVs installed. We published the
proposed AD in the Federal Register on November 18, 2003 (68 FR 65000).
That action proposed to require flex borescope inspections of certain
P/N HPT S2 NGVs installed in CF6-80C2A1, -80C2A2, -80C2A3, -80C2A5, -
80C2A5F, -80C2A8, -80C2B1, -80C2B1F, -80C2B2, -80C2B2F, -80C2B4, -
80C2B4F, -80C2B5F, -80C2B6, -80C2B6F, -80C2B6FA, -80C2B7F, and -80C2D1F
turbofan engines.
Examining the AD Docket: You may examine the AD Docket (including
any comments and service information), by appointment, between 8 a.m.
and 4:30 p.m., Monday through Friday, except Federal holidays. See
ADDRESSES for the location.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments received.
Requests To Limit the Required Inspections
Seven commenters ask that we limit the inspections required by the
proposed AD to those parts listed in paragraph 1.C.(6) of GE Service
Bulletin (SB) No. CF6-80C2 S/B 72-0952, Revision 6, dated May 5, 2003,
and that we revise Table 1 of the proposed AD to clarify the affected
parts. The commenters state that those parts are the population
recommended by the Manufacturer. We agree. We revised the applicability
paragraph and Table 1 of the final rule for consistency with GE SB No.
CF6-80C2 S/B 72-0952, Revision 6, dated May 5, 2003. We also clarified
the applicability of certain P/Ns in Table 1 by adding, ``Insert, P/N
1957M40G01 or P/N 1957M40G02, was installed during modification or
repair,'' to those parts.
Six commenters ask that we limit the inspections required by the
proposed AD to areas of critical stress such as the leading edge and
outer fillet areas of the HPT nozzle airfoil as specified in Paragraph
3.B.(3) of GE SB No. CF6-80C2 S/B 72-0952, Revision 6, dated May 5,
2003. The commenters feel that the proposed AD requires inspecting HPT
blades as well as the nozzles, but that the cracking of the nozzles is
the primary cause of failure of the HPT blade. The commenters feel that
the proposed AD requires inspecting noncritical areas of nozzles. We
agree. We revised paragraph (f) of the final rule to state ``Flex-
borescope inspect the NGVs following paragraphs 3.B.(3) through 3.B.(5)
of the * * *.'' We also deleted paragraphs (f)(1) through (f)(3)(ii)
because they applied to HPT S2 NGVs that have not been repaired.
Requests for a Drawdown Allowance and Credit for Inspections Already
Done
Five commenters ask that we provide an appropriate drawdown
allowance for engines that have exceeded the threshold for the initial
inspection, or provide credit for inspections that have already been
done. The commenters feel that some engines might have already exceeded
the initial limits. We agree that credit should be given for
inspections that were performed before the effective date of the final
rule, however, the proposed AD already provides for that credit by
stating in paragraph (e) of the proposed AD ``You are responsible for
having the actions required by this AD performed within the compliance
times specified, unless the actions have already been done''. We
changed paragraph (f)(2) of the final rule to state ``For engines
listed in paragraphs (f)(1)(i) and (f)(1)(ii) of this AD that are
already beyond the initial inspection thresholds, inspect at or before
accumulating an additional 200 CSO after the effective date of this
AD.''
Request To Add CF6-80C2B8F to the Applicability
Two commenters ask us to add the CF6-80C2B8F engine model to the
Applicability. The commenters state that the engine model was in the SB
before we issued the NPRM. We agree. We have added the CF6-80C2B8F
engine model to the Applicability of the final rule.
Request To Withdraw the NPRM
Two commenters ask us to withdraw the NPRM because they do not feel
there is an issue with safety of flight. One commenter states that they
have not removed any engines for this cause. The other commenter states
that the engine fragments that exited the engine via holes in the low
pressure turbine case were small and caused only minor damage to the
airplane. We do not agree. We identified an unsafe condition after an
uncontained engine failure. We provided a discussion of the cause of
the uncontained engine failure and how the condition could affect other
engines of the same type design. We are issuing this AD to prevent
future occurrences of the same unsafe condition.
Request To Change Blade Failure to Blade Separation
One commenter asks us to change ``blade failure'' to ``blade
separation.'' The commenter states this is consistent with using the
term failure when the failure of the part is the primary cause. We
agree. We have changed ``blade failure'' to ``blade separation'' in the
final rule.
Request To Change CSO to CSN
One commenter asks us to state the inspection compliance times for
new nozzles in paragraph (f)(2)(i) through (iii) in terms of ``CSN.''
The commenter feels this will clarify the requirements. We agree that
the change would have clarified the requirements of the original NPRM.
However, based on previous comments, the final rule will apply only to
repaired or modified nozzles and the paragraphs that the commenter asks
us to change will not be included in the final rule.
Requests To Limit Reinspection Requirements
Two commenters ask us to limit the reinspection requirements in
paragraph (g) for the outer fillet to Figure 5, sheets 1 and 2 of GE SB
No. CF6-80C2 S/B 72-0952, Revision 6, dated May 5, 2003. The commenters
state that those sheets are the specific inspection requirements for
cracking in the outer fillet. We agree. We added ``Sheets 1 and 2'' to
paragraph (g) of the final rule.
Requests To Change the Reinspection intervals
Several commenters ask us to change the reinspection intervals that
are incorporated by reference in paragraph (g). The commenters feel
that the requirement to ``reinspect at the next regular S2 Blade
Inspection'' as stated in Figure 5 of GE SB No. CF6-80C2 S/B 72-0952,
Revision 6, dated May 5, 2003, might be misleading. Although the next
regular S2 Blade Inspection should coincide with 250 cycles-since-last-
inspection (CSLI) for CF6-80C2D1F engines with 5.0 or more cycles per
flight leg and 400 CSLI for all other engines, the lack of specific
cyclic limits might cause confusion. We agree. We added new paragraphs
(h), (h)(1), and (h)(2) to the final rule to define the next regular S2
Blade Inspection as cyclic limits of 250 and 400 CSLI respectively.
[[Page 62573]]
Request To Delete or Change the Paragraph Relating To Operation as More
Than One Engine Configuration
Two commenters ask us to delete or change paragraph (h) of this AD,
``Engines Operated as More than One Engine Model Configuration (Thrust
Level).'' Both commenters feel that we should delete paragraph (h)
because the inspections are limited to repaired nozzles. One commenter
also feels that we need a provision for engines that have operated at
different thrust levels (i.e., reconfigured from one model to another
model) before the initial inspection. We agree. We changed paragraph
(i) of the final rule to require performing the initial inspection at
the lowest applicable inspection threshold, and reinspection intervals
associated with the current engine model configuration.
Conclusion
We have carefully reviewed the available data, including the
comments received, and determined that air safety and the public
interest require adopting the AD with the changes described previously.
We have determined that these changes will neither increase the
economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
There are about 1,100 GE CF6-80C2 turbofan engines of the affected
design in the worldwide fleet. We estimate that this AD will affect 300
of these engines installed on airplanes of U.S. registry. We also
estimate that it will take about 2 work hours per engine to perform the
inspections on engines that exhibit no damage, and therefore require no
mapping of damage, and that the average labor rate is $65 per work
hour. Based on these figures, we estimate the total cost of this AD to
U.S. operators to be $39,000.
Regulatory Findings
We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD will not have a
substantial direct effect 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.
For the reasons discussed above, I certify that this AD:
(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.
We prepared a summary of the costs to comply with this AD and
placed it in the AD Docket. You may get a copy of this summary by
sending a request to us at the address listed under ADDRESSES. Include
``AD Docket No. 2003-NE-43-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 14 CFR part
39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
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]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive:
2004-22-07 General Electric Company: Amendment 39-13835. Docket No.
2003-NE-43-AD.
Effective Date
(a) This airworthiness directive (AD) becomes effective December
1, 2004.
Affected ADs
(b) None.
Applicability
(c) This AD applies to General Electric Company (GE) CF6-80C2A1,
-80C2A2, -80C2A3, -80C2A5, -80C2A5F, -80C2A8, -80C2B1, -80C2B1F, -
80C2B2, -80C2B2F, -80C2B4, -80C2B4F, -80C2B5F, -80C2B6, -80C2B6F, -
80C2B6FA, -80C2B7F, -80C2B8F, and -80C2D1F turbofan engines, with
the part numbers (P/Ns) of high pressure turbine (HPT) stage 2
nozzle guide vanes (HPT S2 NGVs) listed in the following Table 1,
installed:
Table 1.--Affected HPT S2 NGVs
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HPT S2 NGV: Provided that:
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P/N 1347M66G03, P/N 1347M66G04, and P/ Insert, P/N 1957M40G01 or P/N
Ns 1815M81G01 through 1815M81G07. 1957M40G02, was installed
during repair.
P/Ns 9373M80G07 through 9373M80G22, and Insert, P/N 1957M40G01 or P/N
P/Ns 9373M80G25 through 9373M80G32. 1957M40G02, was installed
during repair, or NGV was
repaired by GE between April
1, 1998 through September 30,
1999.
P/Ns 9373M80G33 through 9373M80G36..... Part was repaired.
P/Ns 2080M38G01 through 2080M38G16, and Insert, P/N 1957M40G01 or P/N
P/Ns 2080M38G19 through 2080M38G24. 1957M40G02, was installed
during modification or repair.
P/Ns 2080M19G01 through 2080M19G04, P/ Insert, P/N 1957M40G01 or P/N
Ns 2080M19G07 through 2080M19G16, P/Ns 1957M40G02, was installed
2080M19G19 through 2080M19G46, P/Ns during modification or repair.
2080M19G49 through 2080M19G70, and P/
Ns 2080M19G73 through 2080M19G80.
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These engines are installed on, but not limited to, Airbus A300,
Airbus A310, Boeing 747, Boeing 767, and McDonnell Douglas MD-11
airplanes.
Unsafe Condition
(d) This AD results from an uncontained engine failure due to
HPT S2 NGV distress. We are issuing this AD to prevent blade
separation from HPT S2 NGV distress, which could result in an
uncontained engine failure.
Compliance
(e) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Initial Flex Borescope Inspection of NGVs
(f) Flex-borescope inspect the NGVs following paragraph 3.B.(3)
through 3.B.(5) of Accomplishment Instructions of GE Service
Bulletin (SB) No. CF6-80C2 S/B 72-0952, Revision 6, dated May 5,
2003, as follows:
[[Page 62574]]
Initial Inspection Thresholds
(1) For all P/N NGVs, initial-inspect after the effective date
of this AD at the following applicable initial inspection
thresholds:
(i) For CF6-80C2A2, -80C2B2, and -80C2B2F engines, inspect at or
before accumulating 1,600 HPT cycles-since-overhaul (CSO).
(ii) For CF6-80C2A1, -80C2A3, -80C2A5, -80C2A5F, -80C2A8, -
80C2B1, -80C2B1F, -80C2B4, -80C2B4F, -80C2B5F, -80C2B6, -80C2B6F, -
80C2B6FA, -80C2B7F, -80C2B8F, and -80C2D1F engines, inspect at or
before accumulating 800 CSO.
(2) For engines listed in paragraphs (f)(1)(i) and (f)(1)(ii) of
this AD that are already beyond the initial inspection thresholds,
inspect at or before accumulating an additional 200 CSO after the
effective date of this AD.
Reinspection
(g) Reinspect or remove from service NGVs following the
Conditions and Reinspection intervals listed in the ``Inspection
Table for Cracking in the Airfoil Outer Fillet'', Figure 5, Sheets 1
and 2, of GE SB No. CF6-80C2 S/B 72-0952, Revision 6, dated May 5,
2003.
(h) If the recommendation contained in Figure 5, Sheets 1 and 2,
of GE SB No. CF6-80C2 S/B 72-0952, Revision 6, dated May 5, 2003,
states ``reinspect at next regular S2 Blade inspection,'' then for
the purposes of this AD, the next regular S2 Blade Inspection must
be within the following intervals:
(1) For CF6-80C2D1F engines with 5.0 or more cycles per flight
leg, the next regular S2 Blade inspection means within 250 cycles-
since-last-inspection (CSLI).
(2) For all other engines listed in paragraph (c) of this AD,
the next regular S2 Blade inspection means within 400 CSLI.
Engines Operated as More Than One Engine Model Configuration (Thrust
Level)
(i) For NGVs installed in engines operated as more than one
engine model configuration (thrust level), use the lowest applicable
initial inspection threshold, and use the reinspection intervals
associated with the current engine model.
Alternative Methods of Compliance
(j) The Manager, Engine Certification Office, has the authority
to approve alternative methods of compliance for this AD if
requested using the procedures found in 14 CFR 39.19.
Material Incorporated by Reference
(k) You must use GE Service Bulletin No. CF6-80C2 S/B 72-0952,
Revision 6, dated May 5, 2003, to perform the inspections and
removals required by this AD. The Director of the Federal Register
approved the incorporation by reference of this service bulletin in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You can get a
copy from General Electric Company via Lockheed Martin Technology
Services, 10525 Chester Road, suite C, Cincinnati, Ohio 45215,
telephone (513) 672-8400; fax (513) 672-8422. You can review copies
at the FAA, New England Region, Office of the Regional Counsel, 12
New England Executive Park, Burlington, MA; or at the National
Archives and Records Administration (NARA). For information on the
availability of this material at NARA, call 202-741-6030, or go to:
http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html
.
Related Information
(l) None.
Issued in Burlington, Massachusetts, on October 20, 2004.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 04-23929 Filed 10-26-04; 8:45 am]
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