[Federal Register: September 22, 2004 (Volume 69, Number 183)]
[Proposed Rules]
[Page 56730-56733]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr22se04-20]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2004-19144; Directorate Identifier 2003-NE-18-AD]
RIN 2120-AA64
Airworthiness Directives; General Electric Company (GE) CF6-80C2
and CF6-80E1 Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain GE CF6-80C2 and CF6-80E1 turbofan engines. This proposed AD
would require you to:
Inspect the high pressure compressor rotor (HPCR) stage
11-14 spool shaft for circumferential repair cuts, and
Repair or replace the spool shaft if you find certain
circumferential cuts.
This proposed AD results from an updated stress analysis. We are
proposing this AD to prevent failure of the HPCR stage 11-14 spool
shaft due to low-cycle fatigue that could result in an uncontained
engine failure.
DATES: We must receive any comments on this proposed AD by November 22,
2004.
ADDRESSES: Use one of the following addresses to send comments on this
proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide rulemaking Web site: Go to http://www.regulations.gov
and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401,
Washington, DC 20590-001.
Fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
You can get the service information identified in this proposed 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 comments on this proposed AD in the AD docket
on the Internet at http://dms.dot.gov.
FOR FURTHER INFORMATION CONTACT: Karen Curtis, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803; telephone (781) 238-
7192; fax (781) 238-7199.
SUPPLEMENTARY INFORMATION: We invite you to submit any written relevant
data, views, or arguments regarding this proposal. Send your comments
to an address listed under ADDRESSES. Include ``Docket No. FAA-2004-
19144; Directorate Identifier 2003-NE-18-AD'' in the subject line of
your comments. We specifically invite comments on the overall
regulatory, economic, environmental, and energy aspects of the proposed
AD. We will consider all comments received by the closing date and may
amend the proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this proposed AD. Using the search function of the
DMS Web site, anyone can find and read the comments in any of our
dockets, including the name of the individual who sent the comment (or
signed the comment on behalf of an association, business, labor union,
etc.). You may review the DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78) or you
may visit http://dms.dot.gov.
We are reviewing the writing style we currently use in regulatory
documents. We are interested in your comments on whether the style of
this document is clear, and your suggestions to improve the clarity of
our communications that affect you. You can get more information about
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.Examining
the AD Docket
You may examine the docket that contains the proposal, any comments
received and, any final disposition in person at the DMS Docket Offices
between 9 a.m. and 5 p.m., Monday
[[Page 56731]]
through Friday, except Federal holidays. The Docket Office (telephone
(800) 647-5227) is located on the plaza level of the Department of
Transportation Nassif Building at the street address stated in
ADDRESSES. Comments will be available in the AD docket shortly after
the DMS receives them.
Discussion
In 1996, GE developed a circumferential cut repair to remove
damaged material from seal wire grooves in the outer rim of HPCR stage
11-14 spool shafts installed in certain CF6-80C2 and CF6-80E1 turbofan
engines. The damage was due to wear of the seal wire from engine
operation. At that time, analysis showed that there was no impact on
spool shaft life from the repair geometry. GE performed updated stress
analyses in 1999 and 2003. Those stress analyses showed that the
circumferential cut geometry resulted in a high-stress concentration.
This high-stress concentration could result in a service life that is
lower than the published service life of the spool shaft, depending on
the spool shaft part number (P/N) and location of the repair. GE
reports that as many as 135 CF6-80C2 and CF6-80E1 HPCR 11-14 spool
shafts have had this repair. This condition, if not corrected, could
result in failure of the HPCR stage 11-14 spool shaft due to low-cycle
fatigue that could result in an uncontained engine failure.
Relevant Service Information
We have reviewed and approved the technical contents of GE Aircraft
Engines (GEAE) Service Bulletins (SBs) CF6-80C2 S/B 72-1052, Revision
01, dated February 5, 2004; and CF6-80E1 S/B 72-0232, Revision 01,
dated February 5, 2004, that describe procedures for inspection and
repair of the circumferential cuts in the seal wire grooves of the HPCR
stage 11-14 spool shaft.
Differences Between the Proposed AD and the Manufacturer's Service
Information
This proposed AD does not require the operator to take further
action when a circumferential cut repair is on the forward seal wire
groove of the stage 14 disk of a CF6-80E1 or CF6-80C2 Group 2 spool
shaft. GEAE, however, recommends repairing these disks at the next
exposure, regardless of the number of cycles-since-repair.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an
unsafe condition that is likely to exist or develop on other products
of this same type design. We are proposing this AD, which would
require:
Inspection of the spool shaft for circumferential repair
cuts at the next piece-part level exposure, but not to exceed a
specific service cap specified in this proposed AD, and
Repair or replacement of certain spool shafts.
You must use the service information described previously to
perform these proposed actions.
Costs of Compliance
There are approximately 135 GE CF6-80C2 and CF6-80E1 turbofan
engines of the affected design in the worldwide fleet. We estimate that
27 engines installed on airplanes of U.S. registry would be affected by
this proposed AD. We also estimate that it would take about 1 work hour
per engine to inspect for the location of previous circumferential cut
repairs and 5 work hours per engine to repair the spool shaft. We
estimate that 24 engines would be repaired and that three spool shafts
would be replaced. The average labor rate is $65 per work hour. Each
replacement spool shaft would cost approximately $447,400. Based on
these figures, we estimate the total cost of the proposed AD to U.S.
operators to be $1,351,755.
Regulatory Findings
We have determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would 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 the proposed
regulation:
1. Is not a ``significant regulatory action'' under Executive Order
12866;
2. Is not a ``significant rule'' under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979); and
3. Would 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 proposal 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-18-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Under the authority delegated to me by the Administrator, the
Federal Aviation Administration proposes to amend 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. The FAA amends Sec. 39.13 by adding the following new
airworthiness directive:
General Electric Company: Docket No. FAA-2004-19144; Directorate
Identifier 2003-NE-18-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive
comments on this airworthiness directive (AD) action by November 22,
2004.
Affected ADs
(b) None.
Applicability
(c) This AD applies to certain GE CF6-80C2 and CF6-80E1 turbofan
engines that have a high pressure compressor rotor (HPCR) stage 11-
14 spool shaft with a part number (P/N) listed in Table 1 of this AD
and that had a seal wire groove repaired using a circumferential cut
at a location specified in Table 2 of this AD. These engines are
installed on, but not limited to, Airbus Industrie A300, A310, and
A330 series airplanes and Boeing 747, 767, and MD-11 series
airplanes.
Table 1.--Stage 11-14 Spool Shaft P/Ns By Engine Model and Forging Group Designations
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Engine model Stage 11-14 spool shaft P/Ns Forging group designations
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CF6-80C2................................ 9380M30G07, 9380M30G08, Group 1.
9380M30G09, 9380M30G10,
9380M30G12, 1509M71G02,
1509M71G03, 1509M71G04, and
1509M71G05.
[[Page 56732]]
CF6-80C2................................ 1531M21G01, 1531M21G02, Group 2.
1531M21G04, 1509M71G06,
1509M71G07, 1509M71G08,
1509M71G11, 1509M71G12,
1703M74G01, and 1703M74G03.
CF6-80E1................................ 1509M71G11, 1509M71G12, Not Applicable.
1509M71G13, 1644M99G03,
1703M74G01, and 1703M74G03.
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Unsafe Condition
(d) This AD results from an updated stress analysis. We are
issuing this AD to prevent failure of the HPCR stage 11-14 spool
shaft due to low-cycle fatigue that 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.
CF6-80C2 Engines
(f) For CF6-80C2 series engines with HPCR stage 11-14 spool
shaft serial numbers listed in 1.A.(2) of GE Aircraft Engines (GEAE)
Service Bulletin (SB) No. CF6-80C2 S/B 72-1052, Revision 1, dated
February 5, 2004, inspect the spool shaft for the location of the
circumferential cut repair at the next piece-part exposure.
(1) If the stage and location of the repair is specified in the
engine records, inspect prior to exceeding the cycles-since-repair
(CSR) limit specified in the column titled, Replace By (CSR), in
Table 2.
(2) If the stage or location of the repair is not known from the
engine records, remove the spool shaft for inspection before
exceeding 4,200 CSR for the Group 1 or before exceeding 10,000 CSR
for Group 2. Use 3.A.(1) of the Accomplishment Instructions of GEAE
SB No. CF6-80C2 S/B 72-1052, Revision 1, dated February 5, 2004, for
the inspection. Table 2 follows:
Table 2.--Repair and Replacement Limits for Spool Shafts by Forging Group and Location of the Circumferential
Cut Repair
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Location of
Engine model Forging group Stage circumferential Repair by (CSR) Replace by
(from table 1) cut repair limit (CSR) limit
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(1) CF6-80C2.................. Group 1.......... 14 (i) Aft Seal Wire 3,600........... 4,200
Groove--Not in
Area X.
(ii) Aft Seal None--Replace 4,200
Wire Groove--In spool.
Area X.
(iii) Forward 7,100........... 7,100
Seal Wire
Groove--Not in
Area X.
(iv) Forward Seal None--Replace 7,100
Wire Groove--In spool.
Area X.
(2) CF6-80C2.................. Group 1.......... 13 (i) Aft Seal Wire 7,100........... 7,100
Groove--Not in
Area X.
(ii) Aft Seal 2,740........... 7,100
Wire Groove--In
Area X.
(iii) Forward 7,100........... 7,100
Seal Wire
Groove--Not in
Area X.
(iv) Forward Seal 7,100........... 7,100
Wire Groove--In
Area X.
(3) CF6-80C2.................. Group 1.......... 12 Aft Seal Wire 7,100........... 7,100
Groove--In Area
X.
(4) CF6-80C2.................. Group 2.......... 14 (i) Aft Seal Wire 13,700.......... 13,700
Groove--Not in
Area X.
(ii) Aft Seal None--Replace 13,700
Wire Groove--In spool.
Area X.
(iii) Forward 9,830........... 10,000
Seal Wire
Groove--In Area
X.
(5) CF6-80C2.................. Group 2.......... 13 (i) Aft Seal Wire 9,830........... 10,000
Groove--In Area
X.
(ii) Forward Seal 9,830........... 10,000
Wire Groove--In
Area X.
(6) CF6-80C2.................. Group 2.......... 12 Aft Seal Wire 9,830........... 10,000
Groove--In Area
X.
(7) CF6-80E1.................. Not Applicable... 14 (i) Aft Seal Wire 11,600.......... 11,600
Groove--Not in
Area X.
(ii) Aft Seal None--Replace 11,600
Wire Groove--In spool.
Area X.
(iii) Forward 8,080........... 11,600
Seal Wire
Groove--In Area
X.
(8) CF6-80E1.................. Not Applicable... 13 (i) Aft Seal Wire 8,080........... 11,600
Groove--In Area
X.
(ii) Forward Seal 8,080........... 11,600
Wire Groove--In
Area X.
(9) CF6-80E1.................. Not Applicable... 12 Aft Seal Wire 8,080........... 11,600
Groove--In Area
X.
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(g) If you have a Group 2 spool shaft, and the circumferential
cut repair is in the Stage 14 forward location, and not in Area X,
no further action is required by this AD. However, GEAE recommends
that you repair these spools at the next exposure of the spool
shaft.
Replacement of the Spool Shaft
(h) If the spool shaft exceeds the CSR limit in the column
titled, Replace by (CSR), in Table 2 of this AD, replace the spool
shaft within 420 cycles-in-service (CIS) after the effective date of
this AD or within the published part life limit, whichever occurs
first.
Repair of the Spool Shaft
(i) You may repair the spool if the CSR on the spool shaft are
fewer than or equal to the limit in the column titled, Repair by
(CSR), in Table 2 of this AD. Use 3.B. of the Accomplishment
Instructions of GEAE SB CF6-80C2 S/B 72-1052, Revision 01, dated
February 5, 2004, for the repair.
CF6-80E1 Engines
(j) For CF6-80E1 series engines with HPCR stage 11-14 spool
shafts with SNs listed in 1.A.(2) of GEAE SB No. CF6-80E1 S/B 72-
0232, Revision 01, dated February 5, 2004, do the following:
(1) Inspect the spool shaft for the location of the cut
circumferential repair at the next piece-part exposure, but before
exceeding 11,600 CSR. Use 3.A.(1) of the Accomplishment Instructions
of GEAE SB No. CF6-80E1 S/B 72-0232, Revision 01, dated February 5,
2004 for the inspection.
(2) If the circumferential cut repair is in the Stage 14 forward
location, and not in Area X, no further action is required by this
AD. However, GEAE recommends that you repair these spools at the
next exposure of the spool shaft.
[[Page 56733]]
Replacement of the Spool Shaft
(k) If the CSR are higher than 11,600 CSR, replace the spool
shaft within 420 CIS after the effective date of this AD or within
the published part life limit, whichever occurs first.
Repair of the Spool Shaft
(l) You may repair the spool if the CSR on the spool shaft are
fewer than or equal to the limit in the column titled, Repair by
(CSR), in Table 2 of this AD. Use 3.B. of the Accomplishment
Instructions of GEAE SB CF6-80E1 S/B 72-0232, Revision 01, dated
February 5, 2004, for the repair.
Alternative Methods of Compliance (AMOCs)
(m) 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
(n) None.
Related Information
(o) None.
Issued in Burlington, Massachusetts, on September 15, 2004.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 04-21275 Filed 9-21-04; 8:45 am]
BILLING CODE 4910-13-P