[Federal Register Volume 70, Number 162 (Tuesday, August 23, 2005)]
[Rules and Regulations]
[Pages 49178-49182]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-16454]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-19144; Directorate Identifier 2003-NE-18-AD; 
Amendment 39-14226; AD 2005-17-05]
RIN 2120-AA64


Airworthiness Directives; General Electric Company (GE) CF6-80C2 
and CF6-80E1 Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain GE CF6-80C2 and CF6-80E1 turbofan engines. This AD requires you 
to inspect the high pressure compressor rotor (HPCR) stage 11-14 spool 
shaft for circumferential repair cuts, and to repair or replace the 
spool shaft if you find certain circumferential cuts. 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.

DATES: This AD becomes effective September 27, 2005. The Director of 
the Federal Register approved the incorporation by reference of certain 
publications listed in the regulations as of September 27, 2005.

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 on the Internet at http://dms.dot.gov 
or in Room PL-401 on the plaza level of the

[[Page 49179]]

Nassif Building, 400 Seventh Street, SW., Washington, DC.

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: The FAA proposed to amend 14 CFR part 39 
with a proposed airworthiness directive (AD). The proposed AD applies 
to certain GE CF6-80C2 and CF6-80E1 turbofan engines. We published the 
proposed AD in the Federal Register on September 22, 2004 (69 FR 
56730). That action proposed to 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.

Examining the AD Docket

    You may examine the docket that contains the AD, any comments 
received, and any final disposition in person at the Docket Management 
System (DMS) Docket Office between 9 a.m. and 5 p.m., Monday 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.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Request To Add a Definition

    One commenter requests that for clarity, we add a definition for 
cycles-since-repair (CSR) to the AD. We agree and have added a 
definition to the compliance section. That definition states that for 
the purposes of this AD, CSR limit is the current cycles-since-new 
(CSN) minus the CSN at the time of the repair.

Request To Add Instructions

    One commenter requests that for clarity, we add instructions to the 
compliance section if the CSR limit cannot be determined from the 
engine records. We agree and have added a sentence to the compliance 
section. That sentence states that if the CSR limit cannot be 
determined from the engine records, then CSN must be used.

Request for Document or Procedure References

    One commenter requests that we add document or procedure references 
such as Repair Documents, Service Bulletin numbers, and Shop Manual 
tasks for the circumferential repairs, to help the commenter determine 
affected spools. We do not agree. The AD references the applicable GE 
Service Bulletins, which include the lists of affected parts by serial 
number (SN). The AD is only applicable to those parts. Additional 
references are not needed to determine if the operator has an affected 
part.

Request To Exclude Spools That Previously Complied

    One commenter requests that the AD be modified to exclude spools 
that have previously complied with GEAE Service Bulletin (SB) No. CF6-
80C2 S/B 72-1052, Revision 01, dated February 5, 2004, or certain 
revisions of engine shop manual (ESM) section 72-31-08 or ESM section 
72-00-31. We partially agree. We agree that no further action is 
required for spools that have already complied with GEAE SB No. CF6-
80C2 S/B 72-1052, Revision 01, dated February 5, 2004. The AD clearly 
states in paragraph (e) that the AD actions are only required if the 
actions are not already done.
    We do not agree that accomplishment of ESM section 72-31-08 or 72-
00-31 is equivalent to compliance with GEAE SB No. CF6-80C2 S/B 72-
1052, Revision 01, dated February 5, 2004. ESM section 72-31-08, 
Revision 60 or later does contain the same repair procedure (Repair 12) 
referenced in the accomplishment instructions of the SB and 
incorporated by reference in this AD. Credit for repairs done before 
the effective date of the AD using ESM section 72-31-08, Revision 60 or 
later, should be requested using the alternative methods of compliance 
procedure described in this AD. However, ESM 72-00-31 does not include 
the necessary repair instructions. Therefore, we have not changed the 
AD to incorporate this comment.

Request To Add a Reference to List of Affected SNs

    One commenter requests that Applicability paragraph (c) of the AD 
be modified to include a reference to the list of affected SNs of stage 
11-14 spool shafts in the manufacturer's SBs. The commenter states that 
this additional information would clarify that the AD is only intended 
to apply to those specific spools and not the entire fleet. We 
partially agree. We agree that Applicability paragraph (c) would be 
clearer if it states that the list of affected SNs can be found in the 
referenced service bulletins. We have added a sentence to Applicability 
paragraph (c) that states the affected stage 11-14 spool shafts are 
identified by SN in the GE service information described in paragraphs 
(f) and (j) of this AD.

Request To Clarify Number of Affected Stage 11-14 Spool Shafts

    One commenter requests that the number of affected stage 11-14 
spool shafts be clarified, as the number in GEAE SB No. CF6-80C2 S/B 
72-1052, Revision 01, dated February 5, 2004, and in the Supplementary 
Information of the NPRM are not the same.
    We do not agree. The statement the commenter is referring to in the 
Supplementary Information of the NPRM states that GE reports that as 
many as 135 CF6-80C2 and CF6-80E1 HPCR 11-14 spool shafts have had this 
(circumferential cut) repair. This quantity is the combined number of 
affected spool shafts listed in not one, but two SBs, which are the SB 
for CF6-80C2 engines and the SB for CF6-80E1 engines. Since the 
issuance of the NPRM, however, these SBs have been revised to correct a 
few errors in the SN lists of affected spool shafts. The revised SBs 
referenced in this AD are GEAE SB No. CF6-80C2 S/B 72-1052, Revision 
02, dated May 25, 2005, and GEAE SB No. CF6-80E1 S/B 72-0232, Revision 
01, dated February 5, 2004. Therefore, we have not changed the AD to 
address this comment.

Request To Include List of Affected Stage 11-14 Spool Shafts in AD

    One commenter requests that we include in the AD the list of 
affected stage 11-14 spool shafts, instead of referring readers to the 
SBs for the lists, to avoid the potential for confusion. The commenter 
also requests that we delete the stage 11-14 spool shaft SN MPOAP580 
from the list of affected spools in the AD, suggesting that only stage 
11 of spool shaft SN MPOAP580 was reworked, and so the proposed AD is 
inapplicable to that spool.
    We do not agree that referring readers to the SBs for the lists is 
confusing. We believe it would be confusing to maintain lists of 
affected SNs in both the AD and the SBs. We agree that the AD doesn't 
affect spools repaired on stage 11. We also verified through the 
manufacturer that spool SN MPOAP580 was repaired in only stage 11. This 
SN spool shaft has been deleted from the revised SBs.

[[Page 49180]]

Request To Clarify Paragraph (f)

    One commenter requests that compliance section paragraph (f) be 
clarified by adding the words ``not to exceed the life limits specified 
in Table 2 in the column entitled Replace by (CSR) Limit'', to the end 
of the sentence. We do not agree. Compliance section paragraphs (f)(1) 
and (f)(2) already include this necessary ``not to exceed'' 
information.

Request for Additional Cycles-in-Service

    One commenter requests that up to 420 additional cycles-in-service 
(CIS) be granted for those affected spools that will have accumulated 
more cycles than the ``Repair By Limit'' but are within 420 cycles of 
the ``Replace By Limit'' on the effective date of the AD. The commenter 
states that this would provide margin for those operators suffering 
heavy impact from this AD. The commenter notes that paragraph (h) of 
the proposed AD provides an allowance of 420 CIS if an affected spool 
has already accumulated more cycles than the ``Replace by Limit'' on 
the effective date of the AD. We agree, and revised the compliance 
section based on this request.

Request To Include a Note

    The same commenter requests that a note be included in the AD to 
specify that execution of the Accomplishment Instructions of GEAE SB 
No. CF6-80C2 S/B 72-1052, Revision 01, dated February 5, 2004, is 
considered terminating action for the AD. The commenter is unclear 
whether or not the SB is terminating action for the AD.
    We do not agree. The AD requires that spools either be repaired or 
replaced. Once a spool has been repaired or replaced, no further action 
is required.

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 approximately 173 GE CF6-80C2 and CF6-80E1 turbofan 
engines of the affected design in the worldwide fleet. We estimate that 
24 engines installed on airplanes of U.S. registry will be affected by 
this AD. We also estimate that it will take about one 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 will be repaired and that three spool shafts 
will be replaced. The average labor rate is $65 per work hour. Each 
replacement spool shaft will cost approximately $447,400. Based on 
these figures, we estimate the total cost of the AD to U.S. operators 
to be $1,351,755.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
subtitle VII, part A, subpart III, section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

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 at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
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:

2005-17-05 General Electric Company: Amendment 39-14226. Docket No. 
FAA-2004-19144; Directorate Identifier. 2003-NE-18-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective 
September 27, 2005.

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. The affected stage 
11-14 spool shafts are identified by serial number (SN) in the GE 
service information described in paragraphs (f) and (j) 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
----------------------------------------------------------------------------------------------------------------
              Engine model                    Stage 11-14 Spool Shaft P/Ns         Forging group designations
----------------------------------------------------------------------------------------------------------------
CF6-80C2................................  9380M30G07, 9380M30G08, 9380M30G09,   Group 1.
                                           9380M30G10, 9380M30G12, 1509M71G02,
                                           1509M71G03, 1509M71G04, and
                                           1509M71G05.

[[Page 49181]]

 
CF6-80C2................................  1531M21G01, 1531M21G02, 1531M21G04,   Group 2.
                                           1509M71G06, 1509M71G07, 1509M71G08,
                                           1509M71G11, 1509M71G12, 1703M74G01,
                                           and 1703M74G03.
CF6-80E1................................  1509M71G11, 1509M71G12, 1509M71G13,   Not Applicable.
                                           1644M99G03, 1703M74G01, and
                                           1703M74G03.
----------------------------------------------------------------------------------------------------------------

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 SNs listed in 1.A.(2) of GE Aircraft Engines (GEAE) Service 
Bulletin (SB) No. CF6-80C2 S/B 72-1052, Revision 02, dated May 25, 
2005, 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) For the purposes of this AD, CSR limit is defined as the 
current cycles-since-new (CSN) minus the CSN at the time of the 
repair.
    (3) If the CSR limit cannot be determined from the engine 
records, then CSN must be used.
    (4) 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 02, dated May 25, 2005, 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
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                     Location of
            Engine model               Forging group (from Table     Stage       circumferential cut           Repair by (CSR) limit          Replace by
                                                  1)                                    repair                                               (CSR) limit
--------------------------------------------------------------------------------------------------------------------------------------------------------
(1) CF6-80C2........................  Group 1...................           14  (i) Aft Seal Wire        3,600..............................        4,200
                                                                                Groove Not in Area X.
                                                                               (ii) Aft Seal Wire       None--Replace spool................        4,200
                                                                                Groove--In Area X.
                                                                               (iii) Forward Seal Wire  7,100..............................        7,100
                                                                                Groove--Not in Area X.
                                                                               (iv) Forward Seal Wire   None--Replace spool................        7,100
                                                                                Groove--In Area X.
(2) CF6-80C2........................  Group 1...................           13  (i) Aft Seal Wire        7,100..............................        7,100
                                                                                Groove--Not in Area X.
                                                                               (ii) Aft Seal Wire       2,740..............................        7,100
                                                                                Groove--In Area X.
                                                                               (iii) Forward Seal Wire  7,100..............................        7,100
                                                                                Groove--Not in Area X.
                                                                               (iv) Forward Seal Wire   7,100..............................        7,100
                                                                                Groove--In Area X.
(3) CF6-80C2........................  Group 1...................           12  Aft Seal Wire Groove--   7,100..............................        7,100
                                                                                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 Wire       None--Replace spool................       13,700
                                                                                Groove--In Area X.
                                                                               (iii) Forward Seal Wire  9,830..............................       10,000
                                                                                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 Wire    9,830.............................       10,000
                                                                                Groove--In Area X.
(6) CF6-80C2........................  Group 2...................           12  Aft Seal Wire Groove--   9,830..............................       10,000
                                                                                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 Wire       None--Replace spool................       11,600
                                                                                Groove--In spool Area
                                                                                X.
                                                                               (iii) Forward Seal Wire  8,080..............................       11,600
                                                                                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 Wire   8,080..............................       11,600
                                                                                Groove--In Area X.
(9) CF6-80E1........................  Not Applicable............           12  Aft Seal Wire Groove--   8,080..............................       11,600
                                                                                In Area X.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    (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) After the effective date of this AD, replace spool shafts as 
follows:
    (1) If the spool shaft exceeds the CSR limit in the column 
titled, Repair by (CSR), in Table 2 of this AD, replace the spool 
shaft within 420 cycles-in-service (CIS) or prior to exceeding the 
CSR limit in the column titled, Replace by (CSR), in Table 2 of this 
AD, whichever occurs later.
    (2) 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 CIS or within the published part life limit, 
whichever occurs first.

[[Page 49182]]

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 No. CF6-80C2 S/B 72-1052, Revision 02, dated 
May 25, 2005, 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) For the purposes of this AD, CSR limit is defined as the 
current CSN minus the CSN at the time of the repair.
    (3) If the CSR limit cannot be determined from the engine 
records, then CSN must be used.
    (4) 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.

Replacement of the Spool Shaft

    (k) After the effective date of this AD, replace spool shafts as 
follows:
    (1) If the spool shaft exceeds the CSR limit in the column 
titled, Repair by (CSR), in Table 2 of this AD, replace the spool 
shaft within 420 CIS or prior to exceeding the CSR limit in the 
column titled, Replace by (CSR), in Table 2 of this AD, whichever 
occurs later.
    (2) 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 CIS or within the published part life limit, 
whichever occurs first.

Repair of the Spool Shaft

    (l) You may repair the spool shaft 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

    (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) You must use the service information specified in Table 3 of 
this AD to perform the actions required by this AD.

                                      Table 3.--Incorporation by Reference
----------------------------------------------------------------------------------------------------------------
         Service bulletin No.                      Page                Revision                Date
----------------------------------------------------------------------------------------------------------------
CF6-80C2 S/B 72-1052.................  ALL.........................           02  May 25, 2005.
--------------------------------------
    Total Pages: 11
----------------------------------------------------------------------------------------------------------------
CF6-80E1 S/B 72-0232.................  ALL.........................           01  February 5, 2004.
    Total Pages: 9
----------------------------------------------------------------------------------------------------------------

    The Director of the Federal Register approved the incorporation 
by reference of the documents listed in Table 3 of this AD in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact General 
Electric Company via Lockheed Martin Technology Services, 10525 
Chester Road, Suite C, Cincinnati, Ohio 45215, telephone (513) 672-
8400, fax (513) 672-8422, for a copy of this service information. 
You may review copies at the Docket Management Facility; U.S. 
Department of Transportation, 400 Seventh Street, SW., Nassif 
Building, Room PL-401, Washington, DC 20590-0001, on the internet at 
http://dms.dot.gov, 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/cfr/ibr-locations.html.

    Issued in Burlington, Massachusetts, on August 12, 2005.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 05-16454 Filed 8-22-05; 8:45 am]
BILLING CODE 4910-13-P