AD 2004-04-07

The FAA is superseding two existing airworthiness directives (ADs) for GE CF6-80 series turbofan engines with certain stage 1 high- pressure turbine (HPT) rotor disks. Those ADs currently require initial and repetitive inspections of certain stage 1 HPT rotor disks for cracks in the bottom of the dovetail slot. This action retains the
initial inspection requirement, as a qualification for the mandatory rework procedures for certain disks, and continues repetitive inspections only for the disks for which the rework procedures are not yet defined. This action requires reworking certain disks before further flight. In addition, this AD expands the population of affected engines and removes certain CF6-80E1 series disks from service. This AD results from the manufacturer's investigation and development of a rework procedure that chamfers the aft breakedge of the dovetail slot bottom. We are issuing this AD to detect and prevent cracks in the bottoms of the dovetail slots that could propagate to failure of the disk and cause an uncontained engine failure.

Final rule; request for comments.

2004-04-07 General Electric Company: Amendment 39-13488. Docket No. 2004-NE-05-AD. Supersedes AD 2001-10-07, Amendment 39-12233, and AD 2003-01-05, Amendment 39-13016.

Effective Date

(a) This airworthiness directive (AD) becomes effective March 12, 2004.

Affected ADs

(b) This AD supersedes AD 2001-10-07 and AD 2003-01-05.

Applicability

(c) This AD applies to the General Electric Company (GE) CF6-80 turbofan engine models listed in the following Table 1:

Table 1.--Applicability Models, Part Numbers, Airplanes

Models
Stage 1 high pressure turbine (HPT) rotor disk part Nos. (PNs)
Engines installed on but not limited to
CF6-80A, CF6-80A1, CF6-80A2, CF6-80A3
9234M67G22/G24/G25/G26. 9362M58G02/ G06/G07/G09. 9367M45G02/G04/G09.
Airbus A310 and Boeing 767 airplanes.
CF6-80C2A1, CF6-80C2A2, CF6-80C2A3, CF6-80C2A5, CF6-80C2A8, CF6- 80C2A5F, CF6-80C2B1, CF6-80C2B2,
CF6-80C2B4, CF6-80C2B6,
CF6- 80C2B1F, CF6-80C2B2F, CF6-80C2B4F, CF6-80C2B5F, CF6-80C2B6F, CF6-80C2B6FA, CF6-80C2B7F, CF6-80C2D1F.
1862M23G01. 9392M23G10/G12/G21.
1531M84G02/G06/G08/G10.
Airbus A300, A310, Boeing 747, 767, and McDonnell Douglas MD11 airplanes.
CF6-80E1A2, CF6-80E1A4
1639M41P04
Airbus A330 airplanes.

These engines are installed on, but not limited to, the airplanes listed in Table 1 of this AD.

Unsafe Condition

(d) This AD results from the manufacturer's investigation and development of a rework procedure that chamfers the aft breakedge of the dovetail slot bottom. The actions specified in this AD are intended to detect and prevent cracks in the bottoms of the dovetail slots that could propagate to failure of the disk and cause 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.

CF6-80A, -80A1, -80A2, and -80A3 Engines

Stage 1 HPT Rotor Disks, P/N 9362M58G09, With Chamfered Breakedges

(f) At the next piece-part exposure after the effective date of this AD, for stage 1 HPT rotor disks, P/N 9362M58G09, with SNs listed in Table 2 of this AD, do the following:

Table 2.--SNs of CF6-80A Series Stage 1 HPT Rotor Disk P/N 9362M58G09-- With Chamfered Breakedges

GWN03RD7
GWN042J3
GWN04HRD
GWN04M9K
GWN03TKG
GWN04FW2
GWN04HRE
GWN04M9L
GWN03TKH
GWN04FW3
GWN04HRF
GWN04M9M
GWN03TKJ
GWN04FW4
GWN04HRG
GWN04M9R
GWN03W3M
GWN04FW5
GWN04HRH
GWN04M9T
GWN03W3N
GWN04H0M
GWN04K8N
GWN04M9W
GWN03W3R
GWN04HRA
GWN04M9J

(1) Visually inspect the rotor disks for the presence of a chamfer on the aft breakedges of the dovetail slot bottoms. Use paragraph 3.A. of GE Service Bulletin (SB) No. CF6-80A S/B 72-0788, Revision 2, dated December 17, 2003, to do the inspection.

(2) For disks that have the chamfered breakedges, remark, fluorescent penetrant inspect (FPI), and eddy current inspect (ECI) the rotor disk. Use paragraph 3.A.(1)(a) through 3.A.(1)(b) of the Accomplishment Instructions of GE SB No. CF6-80A S/B 72-0788, Revision 2, dated December 17, 2003, to remark and inspect the rotor disk and remove from service as necessary.

(3) For disks that do not have the chamfered breakedges, inspect, rework and remark the rotor disk. Use paragraph 3.A(2)(a) through 3.A(2)(b) of the Accomplishment Instructions of GE SB No. CF6-80A S/B 72-0788, Revision 2, dated December 17, 2003, to inspect, rework, and remark the disk and remove from service as necessary.

Stage 1 HPT Rotor Disks, P/Ns 9234M67G22, G24, G25, G26, 9367M45G04, G09, 9362M58G02, G06, G07, and 9362M58G09 With SNs Not Listed in Table 2 of This AD

(g) For stage 1 HPT rotor disks, P/Ns 9234M67G22, G24, G25, G26, 9367M45G04, G09, 9362M58G02, G06, G07, and 9362M58G09 with SNs not listed in Table 2 of this AD, inspect, rework, and remark the disks using paragraphs 3.A.(2) through 3.B.(2) of Accomplishment Instructions of GE SB No. CF6-80A S/B 72-0788, Revision 2, dated December 17, 2003, at the following:

(1) For stage 1 HPT rotor disks not installed in engines with both new and old hardware, inspect, rework, remark, and remove from service as necessary before further flight.

(2) For stage 1 HPT rotor disks that have been inspected before the effective date of this AD using any version of GE SB No. CF6-80A S/B 72-0779, inspect, rework, remark, and remove from service as necessary at the next Engine Shop Visit (ESV) using the compliance times in the following Table 3:

Table 3.--Compliance Times For Inspection and Rework of CF6-80A Series Stage 1 HPT Rotor Disks, P/Ns 9234M67G22, G24, G25, G26, 9367M45G04, G09, 9362M58G02, G06, G07, and 9362M58G09 With SNs Not Listed in Table 2 of This AD--Previously Inspected

Stage 1 HPT rotor disk cycles-since-last-inspection (CSLI) on the effective date of this AD
Compliance time for inspection and rework
(i) More than 1,500 CSLI
At the next ESV after the effective date of this AD, but not to exceed 4,500 CSLI.
(ii) 1,500 CSLI or fewer
At the next ESV after the effective date of this AD, but not to exceed 3,500 CSLI.

(3) For stage 1 HPT rotor disks that have not been inspected before the effective date of this AD using any version of GE SB No. CF6-80A S/B 72-0779, inspect, rework, remark, and remove from service as necessary at the next ESV using the compliance times in the following Table 4:

Table 4. Compliance Times for Inspection and Rework of CF6-80A Series Stage 1 HPT Rotor Disks, P/Ns 9234M67G22, G24, G25, G26, 9367M45G04, G09, 9362M58G02, G06, G07, and 9362M58G09 With SNs Not Listed in Table 2 of This AD--Not Previously Inspected

Stage 1 HPT rotor disk cycles-since-new (CSN) on the effective date of this AD
Compliance time for inspection and rework
(i) 10,000 or more CSN
At the next ESV or within 1,000 cycles-in-service (CIS) after the effective date of this AD, whichever occurs first.
(ii) 5,000 or more CSN but fewer than 10,000 CSN
At the next ESV or within 2,400 CIS after the effective date of this AD, whichever occurs first, but before accumulating 11,000 CSN.
(iii) Fewer than 5,000 CSN
At the next ESV or within 3,500 CIS after the effective date of this AD, whichever occurs first, but before accumulating 7,400 CSN.

Stage 1 HPT Rotor Disks, P/N 9367M45G02

(h) For stage 1 HPT rotor disks, P/N 9367M45G02, inspect the rotor disk dovetail slot bottoms and remove the disk from service as necessary using paragraphs 3.A. through 3.C.(10)(i) of Accomplishment Instructions of GE SB No. CF6-80A S/B 72-0779, Revision 1, dated January 22, 2004, at the following times:

(1) For stage 1 HPT rotor disks not installed in engines with both new and old hardware, inspect and remove from service as necessary before further flight.

(2) For stage 1 HPT rotor disks that have been inspected before the effective date of this AD using any version of GE SB No. CF6-80A S/B 72-0779, and had more than zero CSN at the time of that inspection, inspect and remove from service as necessary at each piece-part exposure.

(3) For stage 1 HPT rotor disks that have not been inspected, or were only inspected with zero CSN before the effective date of this AD using any version of GE SB No. CF6-80A S/B 72-0779, inspect and remove from service as necessary at the next ESV using the compliance times in the following Table 5:

Table 5. Compliance Times for Inspection of CF6-80A Series Stage 1 HPT Rotor Disks, P/N 9367M45G02--Not Previously Inspected

Stage 1 HPT rotor disk CSN on the effective date of this AD
Compliance time for initial inspection
(i) 10,000 or more CSN
At the next ESV or within 1,000 CIS after the effective date of this AD, whichever occurs first.
(ii) 5,000 or more CSN but fewer than 10,000 CSN
At the next ESV or within 2,400 CIS after the effective date of this AD, whichever occurs first, but before accumulating 11,000 CSN.
(iii) Fewer than 5,000 CSN
At the next ESV or within 3,500 CIS after the effective date of this AD, whichever occurs first, but before accumulating 7,400 CSN.

(4) Thereafter, inspect at each piece-part exposure, and remove the rotor disk from service if necessary.

CF6-80C2 Series Engines

Stage 1 HPT Rotor Disks, P/N 1531M84G10, With Chamfered Breakedges

(i) At the next piece-part exposure after the effective date of this AD, for stage 1 HPT rotor disks, P/N 1531M84G10, with SNs listed in Table 6 of this AD, do the following:

Table 6.--SNs of CF6-80C2 Series Stage 1 HPT Rotor Disks, P/N 1531M84G10, With Chamfered Breakedges

GWN03111
GWN0369J
GWN03K3F
GWN03RPD
GWN049JM
GWN03114
GWN036JG
GWN03K3G
GWN03RPE
GWN049M7
GWN03501
GWN036JH
GWN03K3H
GWN03RPF
GWN049M8
GWN03699
GWN036JJ
GWN03K3K
GWN03RPG
GWN049M9
GWN03752
GWN036JK
GWN03K3L
GWN0402A
GWN04AEP
GWN03753
GWN036JL
GWN03K3M
GWN0402E
GWN04AER
GWN03754
GWN036JM
GWN03K3N
GWN0402F
GWN04AET
GWN03755
GWN036JN
GWN03K3R
GWN0402G
GWN04ALR
GWN03756
GWN0375A
GWN03K3T
GWN0402H
GWN04ALT
GWN03757
GWN0375C
GWN03K3W
GWN0402J
GWN04ALW
GWN03759
GWN0375D
GWN03K40
GWN0402K
GWN04AM0
GWN03981
GWN0375E
GWN03K6J
GWN0402L
GWN04AM1
GWN03982
GWN037H2
GWN03K7R
GWN0402M
GWN04AM2
GWN03983
GWN0398A
GWN03K7T
GWN0402N
GWN04AM3
GWN03984
GWN0398C
GWN03KR1
GWN0402P
GWN04AM4
GWN03985
GWN039PF
GWN03KR2
GWN040R5
GWN04CGJ
GWN03986
GWN039PG
GWN03KR3
GWN0418A
GWN04CGL
GWN03987
GWN039PH
GWN03KR4
GWN0418C
GWN04CGN
GWN03988
GWN039PJ
GWN03KR5
GWN0418D
GWN04CGT
GWN03989
GWN039PK
GWN03KR6
GWN0418E
GWN04CGW
GWN04026
GWN039PL
GWN03KR7
GWN0418F
GWN04CH3
GWN04027
GWN039PM
GWN03KR8
GWN0418G
GWN04CH5
GWN04028
GWN039PN
GWN03KRA
GWN0418H
GWN04CH8
GWN04029
GWN03A4J
GWN03KRC
GWN0418J
GWN04CH9
GWN04189
GWN03A4K
GWN03KRD
GWN0418K
GWN04CHA
GWN04190
GWN03A4L
GWN03L2D
GWN0418L
GWN04CHC
GWN04191
GWN03A4M
GWN03L2E
GWN0418M
GWN04D52
GWN04366
GWN03A4N
GWN03L2F
GWN0418N
GWN04D54
GWN04722
GWN03A4P
GWN03LNF
GWN0418P
GWN04D55
GWN04726
GWN03A4R
GWN03LNJ
GWN0418R
GWN04D56
GWN04729
GWN03A4T
GWN03LNK
GWN0418T
GWN04D57
GWN031N2
GWN03A4W
GWN03M88
GWN0418W
GWN04D58
GWN031N3
GWN03C12
GWN03M89
GWN044DP
GWN04D59
GWN031N4
GWN03C13
GWN03M8C
GWN0454E
GWN04DPW
GWN031N5
GWN03C14
GWN03M8D
GWN0454F
GWN04DR4
GWN031N6
GWN03CA0
GWN03M8E
GWN0454G
GWN04DR9
GWN031N7
GWN03DC9
GWN03M8F
GWN0454H
GWN04DRE
GWN031N8
GWN03DCA
GWN03M8J
GWN0454J
GWN04DRJ
GWN031N9
GWN03DCC
GWN03M8K
GWN0454K
GWN04E9K
GWN031NA
GWN03DCD
GWN03NHN
GWN0454L
GWN04E9L
GWN031NC
GWN03DCE
GWN03NHP
GWN0454M
GWN04E9M
GWN032G1
GWN03DCF
GWN03NHR
GWN0454N
GWN04E9N
GWN032G2
GWN03DCG
GWN03NHT
GWN045T0
GWN04EM5
GWN032G3
GWN03DCH
GWN03R73
GWN045T1
GWN04EMA
GWN032G4
GWN03DCJ
GWN03R74
GWN045T2
GWN04EMK
GWN032G5
GWN03DCK
GWN03R75
GWN045T3
GWN04EML
GWN032G6
GWN03DCL
GWN03R76
GWN045T4
GWN04EMM
GWN032G7
GWN03DCM
GWN03R77
GWN045T5
GWN04F8N
GWN032G8
GWN03DCN
GWN03R78
GWN045T6
GWN04F8P
GWN032G9
GWN03DCP
GWN03R79
GWN045T7
GWN04FTJ
GWN032GE
GWN03DCR
GWN03R7A
GWN045T8
GWN04FTL
GWN0335P
GWN03DME
GWN03R7C
GWN045T9
GWN04FTM
GWN0335R
GWN03DMF
GWN03R7D
GWN045TA
GWN04FTN
GWN033C5
GWN03ER7
GWN03R7E
GWN045TC
GWN034KR
GWN03ER8
GWN03R7F
GWN045TD
GWN034KT
GWN03ER9
GWN03R7G
GWN045TE
GWN0350M
GWN03ERA
GWN03R7H
GWN045TF
GWN0350N
GWN03FTN
GWN03R9G
GWN045TG
GWN0350P
GWN03FTP
GWN03R9H
GWN045TH
GWN0350R
GWN03FTR
GWN03R9J
GWN046F6
GWN0350T
GWN03FTT
GWN03R9K
GWN046F7
GWN0350W
GWN03FTW
GWN03R9L
GWN046F8
GWN035M5GWN03FW0
GWN03R9M
GWN047LG
GWN035M6
GWN03H56
GWN03R9N
GWN047LH
GWN035M7
GWN03H57
GWN03R9P
GWN047LJ
GWN035M8
GWN03H58
GWN03R9R
GWN047LK
GWN035M9
GWN03HTL
GWN03R9T
GWN047LL
GWN035MA
GWN03HTM
GWN03R9W
GWN048CD
GWN035MC
GWN03HTN
GWN03RA0
GWN048CF
GWN035MD
GWN03HTP
GWN03RA1
GWN048CG
GWN035TH
GWN03HTR
GWN03RA2
GWN048CH
GWN035TJ
GWN03HTT
GWN03RA3
GWN048CJ
GWN035TK
GWN03J8T
GWN03RA4
GWN048CK
GWN035TL
GWN03J8W
GWN03RA5
GWN048CM
GWN035TM
GWN03J90
GWN03RA6
GWN048CN
GWN0369A
GWN03J91
GWN03RA7
GWN048CP
GWN0369C
GWN03J92
GWN03RA8
GWN048CR
GWN0369D
GWN03JNN
GWN03RP7
GWN049GH
GWN0369E
GWN03JNP
GWN03RP9
GWN049GJ
GWN0369G
GWN03K3C
GWN03RPA
GWN049GK
GWN0369H
GWN03K3D
GWN03RPC
GWN049JL

(1) Visually inspect the rotor disks for the presence of a chamfer on the aft breakedges of the dovetail slot bottoms. Use paragraph 3.A. of GE SB No. CF6-80C2 S/B 72-1089, Revision 2, dated December 18, 2003, to do the inspection.

(2) For disks that have the chamfered breakedges, remark, FPI, and ECI the rotor disk. Use paragraph 3.A.(1)(a) through 3.A.(1)(b) of the Accomplishment Instructions of GE SB No. CF6-80C2 S/B 72- 1089, Revision 2, dated December 18, 2003, to remark and inspect the rotor disk, and remove from service as necessary.

(3) For disks that do not have the chamfered breakedges, inspect, rework and remark the rotor disk. Use paragraph 3.A.(2)(a) through 3.A.(2)(b) of the Accomplishment Instructions of GE SB No. CF6-80C2 S/B 72-1089, Revision 2, dated December 18, 2003, to inspect, rework and remark the disk and remove from service as necessary.

Stage 1 HPT Rotor Disks, P/Ns 9392M23G10, G12, G21, 1531M84G02, G06, G08, and 1531M84G10 With SNs Not Listed in Table 6 of This AD

(j) For stage 1 HPT rotor disks, P/Ns 9392M23G10, G12, G21, 1531M84G02, G06, G08, and 1531M84G10 with SNs not listed in Table 6 of this AD, inspect, rework, and remark the disks using paragraphs 3.A.(2) through 3.B.(2) of Accomplishment Instructions of GE SB No. CF6-80C2 S/B 72-1089, Revision 2, dated December 18, 2003, at the following:

(1) For stage 1 HPT rotor disks not installed in engines with both new and old hardware, inspect, rework, remark, and remove from service as necessary before further flight.

(2) For stage 1 HPT rotor disks that have been inspected before the effective date of this AD using GE SB No. CF6-80C2 S/B 72-A1024, Revision 1, dated November 3, 2000, or any version of GE ASB No. CF6-80C2 S/B 72-A1026, inspect, rework, remark, and remove from service as necessary at the next ESV using the compliance times in the following Table 7:

Table 7.--Compliance Times for Inspection and Rework of CF6-80C2 Series Stage 1 HPT Rotor Disks, P/Ns 9392M23G10, G12, G21, 1531M84G02, G06, G08, and 1531M84G10 With SNs Not Listed in Table 6 of This AD-- Previously Inspected

Stage 1 HPT rotor disk cycles-since-inspection (CSI) on the effective date of this AD
Compliance time for inspection and rework
(i) More than 1,500 CSLI
At the next ESV or within 4,500 CSLI after the effective date of this AD, whichever occurs first.
(ii) 1,500 CSLI or fewer
At the next ESV or within 3,500 CSLI after the effective date of this AD, whichever occurs first.

(3) For stage 1 HPT rotor disks that have not been inspected before the effective date of this AD using GE SB No. CF6-80C2 S/B 72-A1024, Revision 1, dated November 3, 2000, or any version of GE ASB No. CF6-80C2 S/B 72-A1026, inspect, rework, remark, and remove from service as necessary at the next ESV using the compliance times in the following Table 8:

Table 8.--Compliance Times for Inspection and Rework of CF6-80C2 Series Stage 1 HPT Rotor Disks, P/Ns 9392M23G10, G12, G21, 1531M84G02, G06, G08, and 1531M84G10 With SNs Not Listed in Table 6 of This AD--Not Previously Inspected

Stage 1 HPT rotor disk cycles-since-new (CSN) on the effective date of this AD
Compliance time for inspection and rework
(i) 10,000 or more CSN
At the next ESV or within 1,000 CIS after the effective date of this AD, whichever occurs first.
(ii) 5,000 or more CSN but fewer than 10,000 CSN
At the next ESV or within 2400 CIS after the effective date of this AD, whichever occurs first, but before accumulating 11,000 CSN
(iii) Fewer than 5,000 CSN.
At the next ESV or within 3,500 CIS after the effective date of this AD, whichever occurs first, but before accumulating 7,400 CSN.

Stage 1 HPT Rotor Disks, P/N 1862M23G01

(k) For stage 1 HPT rotor disk, P/N 1862M23G01, inspect the rotor disk dovetail slot bottoms and remove the disk from service as necessary using paragraphs 3.A. through 3.C.(10)(i) of Accomplishment Instructions of GE ASB No. CF6-80C2 S/B 72-A1026, Revision 2, dated January 22, 2004, at the following times:

(1) For stage 1 HPT rotor disks not installed in engines with both new andold hardware, inspect and remove from service as necessary before further flight.

(2) For stage 1 HPT rotor disks that have been inspected before the effective date of this AD using any version of GE ASB No. CF6- 80C2 S/B 72-A1026, and had more than zero CSN at the time of that inspection, inspect and remove from service as necessary at each piece-part exposure.

(3) For stage 1 HPT rotor disks that have not been inspected, or were only inspected with zero CSN before the effective date of this AD using any version of GE ASB No. CF6-80C2 S/B 72-A1026, inspect and remove from service as necessary at the next ESV using the compliance times in the following Table 9:

Table 9.--Compliance Times for Inspection of CF6-80C2 Series Stage 1 HPT Rotor Disks, P/N 1862M23G01--Not Previously Inspected

Stage 1 HPT rotor disk CSN on the effective date of this AD
Compliance time for initial inspection
(i) 10,000 or more CSN
At the next ESV or within 1,000 CIS after the effectivedate of this AD, whichever occurs first.
(ii) 5,000 or more CSN but fewer than 10,000 CSN
At the next ESV or within 2,400 CIS after the effective date of this AD, whichever occurs first, but before accumulating 11,000 CSN.
(iii) Fewer than 5,000 CSN
At the next ESV or within 3,500 CIS after the effective date of this AD, whichever occurs first, but before accumulating 7,400 CSN.

(4) Thereafter, inspect at each piece-part exposure, and remove the rotor disk from service if necessary.

CF6-80E1A2, A4 Engines

Stage 1 HPT Rotor Disks, P/N 1639M41P04

(l) For stage 1 HPT rotor disks, P/N 1639M41P04, remove the rotor disks from service using paragraphs 3.A.(1) through 3.A.(2) of Accomplishment Instructions of GE SB No. CF6-80E1 S/B 72-0251, dated January 22, 2004, at the following times:

(1) For stage 1 HPT rotor disks currently in service, remove the disk using the compliance times in the following Table 10:

Table 10.--Compliance Times for Removal of CF6-80E1 Stage 1 HPT Rotor Disks, P/N 1639M41P04

Stage 1 HPT rotor disk CSN on the effective date of this AD
Compliance time for removal of disk
(i) More than 10,000 CSN
At the next ESV or within 600 CIS after the effective date of this AD, whichever occurs first.
(ii) More than 5,000 CSN but fewer than or equal to 10,000 CSN
At the next ESV or within 2,500 CIS after the effective date of this AD, whichever occurs first, but before accumulating 10,600 CSN.
(iii) Fewer than or equal to 5,000 CSN
At the next ESV or within 3,500 CIS after the effective date of this AD, whichever occurs first, but before accumulating 7,500 CSN.

(2) After the effective date of this AD, do not install any stage 1 HPT rotor disk, P/N 1639M41P04, into any engine.

Definitions

(m) For the purpose of this AD, the following definitions apply:

(1) An engine shop visit (ESV) is defined as the removal of an engine from an aircraft for maintenance in which a major engine flange isdisassembled after the effective date of this AD. The following actions, either separately or in combination with each other, are not considered ESVs for the purpose of this AD.

(i) The removal of the upper compressor stator case solely for airfoil maintenance.

(ii) The module level inspection of the high-pressure compressor rotor 3-9 spool.

(iii) The replacement of stage 5 high-pressure compressor variable stator vane bushings or lever arms.
(2) Piece-part exposure is defined as when:

(i) The stage 1 HPT rotor disk is considered completely disassembled according to the manufacturer's engine manual or other FAA-approved engine manual; and

(ii) The disk has accumulated more than 100 cycles-in-service since the last piece-part inspection, provided that the part was not damaged or the disassembly is not related to the cause for its removal from the engine.

Reporting Requirements

(n) Within five calendar days of the inspection, report the results of inspections that equal or exceed the reject criteria to: Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive park, Burlington, MA 01803-5299; telephone (781) 238-7128; fax (781) 238-7199. Reporting requirements have been approved by the Office of Management and Budget and assigned OMB control number 2120-0056. Be sure to include the following information:

(1) Engine model in which the stage 1 HPT rotor disk was installed.
(2) Part Number.
(3) Serial Number.
(4) Part CSN.
(5) Part CSLI.
(6) Date and location where inspection was done.

(o) We recommend that you record the inspection information and results on GE Form 1653-1, entitled CF6-80A/80C Stage 1 HPT Disk Dovetail Slot Bottom Inspection. This form is available in any version of GE SB CF6-80A S/B 72-0779, or GE ASB CF6-80C2 S/B 72- A1026. We also recommend that a copy of the data be sent to GE Airline Support Engineering, General Electric Aircraft Engines, Customer Support Center, 1 Neumann Way, Mail Drop RM285, Cincinnati, OH, 45215.

Alternative Methods of Compliance

(p) 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

(q) You must use the service information specified in Table 11 to perform the actions required by this AD. The Director of the Federal Register approved the incorporation by reference of the documents listed in Table 11 of this AD 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 may review copies at the FAA, New England Region, Office of the Regional 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. Table 11 follows:

Table 11.--Incorporation by Reference

Service bulletin no.
Page
Revision
Date
GE SB No. CF6-80E1 S/B 72-0251
Total Pages: 4
All

Original
January 22, 2004.
GE SB No. CF6-80A S/B 72-0779
Total Pages: 34
All

1
January 22, 2004.
GE SB No. CF6-80A S/B 72-0788
Total Pages: 10
All

2
December 17, 2003.
GE ASB No. CF6-80C2 S/B 72-A1026
Total Pages: 38
All

2
January 22, 2004.
GE SB No. CF6-80C2 S/B 72-1089
Total Pages: 11
All

2
December 18, 2003.

Related Information

(r) GE SB No. CF6-80C2 S/B 72-A1024, Revision 1, dated November 3, 2000 also pertains to the subject of this AD.

On May 10, 2001, the FAA issued AD 2001-10- 07, Amendment 39-12233 (66 FR 27592, May 18, 2001). That AD requires initial and repetitive inspections of certain stage 1 HPT rotor disks installed on CF6-80C2 turbofan engines for cracks in the bottoms of the dovetail slots. That AD resulted from a report of an uncontained failure of an engine during a high-power ground run during maintenance. On January 2, 2003, we issued AD 2003-01-05, Amendment 39-13016 (68 FR 1519, January 13, 2003). That AD requires initial and repetitive inspections of certain stage 1 HPT rotor disks installed on CF6-80A series turbofan engines for cracks in the bottoms of the dovetail slots. AD 2003-01-05 resulted from a report of an uncontained failure of a CF6-80A series engine during climb. The manufacturer investigated those two failures as well as findings of cracks on other disks to determine the root cause of the failures. Those investigations showed that the cracks started from toolmarks, broach burrs, damage sustained from improper handling and processing, and other unknown causes. The manufacturer and the FAA have determined that those conditions could also exist on stage 1 HPT rotor disks that are installed in certain CF6-80E1 series turbofan engines. Those conditions, if not corrected, could result in cracks in the bottoms of the dovetail slots that could propagate to failure of the disk and cause an uncontained engine failure.

Actions Since AD 2001-10-07 and AD 2003-01-05 Were Issued

Since we issued those ADs, the manufacturer developed a rework procedure to eliminate the root causes of the cracks. This rework procedure removes potentially damaged material from the breakedge and makes the geometry less susceptible to damage that could lead to cracks in the bottoms of the dovetail slots and subsequent failure. As part of the rework procedure, the disks are remarked with a different part number. The rework replaces the current requirements for initial and repetitive inspections on those disks for which rework is defined.

Stage 1 HPT rotor disks, part number (P/N) 9367M45G02, are an early configuration, and no parts are believed to be in service. These disks do not have rework procedures defined. Therefore the repetitive inspections remain for any disks that may still be in service.

The manufacturer developed a rework procedure for stage 1 HPT rotor disks, P/N 1862M23G01, to address cracks in the forward flange of the thermal shield by machining the profile of the slot bottom. A limited number of these disks were released to the field before the program was discontinued. These disks also do not have rework procedures defined because the chamfered breakedge rework machining was not developed for this limited number of parts.

We are considering additional rulemaking to add eddy current inspections of the bottom of the CF6-80A dovetail slots and the CF6-80A and CF6-80C2 chamfer surfaces to the Airworthiness LimitationsSection of the Instructions for Continued Airworthiness as part of the FAA's "enhanced-disk inspection initiative."

Relevant Service Information

We have reviewed and approved the technical contents of the following GE Service Bulletins (SBs) and Alert Service Bulletin (ASB) that describe procedures for removing, inspecting, and reworking certain stage 1 HPT rotor disks:
SB No. CF6-80E1 S/B 72-0251, dated January 22, 2004;
SB No. CF6-80A S/B 72-0779, Revision 1, dated January 22, 2004;
SB No. CF6-80A S/B 72-0788, Revision 2, dated December 17, 2003;
ASB No. CF6-80C2 S/B 72-A1026, Revision 2, dated January 22, 2004;
SB No. CF6-80C2 S/B 72-1089, Revision 2, dated December 18, 2003.

Differences Between This AD and the Service Information

The differences between this AD and the service information are as follows:

GE SB No. CF6-80A S/B 72-0779, Revision 1, dated January 22, 2004, applies to certain CF6-80A stage 1 HPT rotor disks and requires an initialinspection at next exposure. However, this AD requires only the stage 1 HPT rotor disks, P/N 9367M45G02, to have only an initial inspection at the next shop visit, subject to cycle limitations and subsequent repetitive inspections at each piece part exposure. This AD requires the other HPT rotor disks, to which the SB applies, to have the rework defined in SB No. CF6-80A S/B 72-0788, Revision 2, dated December 17, 2003. This AD also requires the inspection of stage 1 HPT rotor disks, P/N 9367M45G02, which have zero cycles-since-new (CSN) before installation into the engine. The SB does not.

GE ASB No. CF6-80C2 S/B 72-A1026, Revision 2, dated January 22, 2004, applies to certain CF6-80C2 stage 1 HPT rotor disks, and requires initial inspections of the stage 1 HPT rotor disks at the next shop visit. However, this AD requires only the stage 1 HPT rotor disks, P/N 1862M23G01, to have only an initial inspection at the next shop visit, subject to cycle limitations, and subsequent repetitive inspections at each piece-part exposure. This AD requires the other HPT rotor disks, to which this ASB applies, to have the rework defined in SB No. CF6-80C2 S/B 72-1089, Revision 2, dated December 18, 2003. The cycle limitations in the AD are based on the latest risk analysis for CF6-80A and CF6-80C2 engines where the ASB's cycle limitations are based on a risk analysis completed in 2001 for only CF6-80C2 engines. This AD also requires the inspection of stage 1 HPT rotor disks, P/N 1862M23G01, which have zero CSN before installation into the engine. The ASB does not.

There are no differences between GE SB No. CF6- 80A S/B 72-0788, Revision 2, dated December 17, 2003, and GE SB No. CF6-80C2 S/B 72-1089, Revision 2, dated December 18, 2003, and this AD except for the introduction of compliance cycle limitations.

There are no differences between GE SB No. CF6- 80E1 S/B 72-0251, dated January 22, 2004, and this AD.

FAA's Determination and Requirements of This AD

The unsafe condition described previously is likely to exist or develop on other GE CF6-80 series turbofan engines of the same type design. We are issuing this AD to detect and prevent cracks in the bottoms of the dovetail slots that could propagate to failure of the disk and cause an uncontained engine failure. This AD requires rework of the dovetail slot bottom of certain stage 1 rotor disks. The disks must pass an inspection to qualify for the rework. Disks for which the rework has not been defined must continue to receive initial and repetitive inspections. In addition, this AD expands the population of affected engines and removes from service certain CF6-80E1 series disks. You must use the service information described previously to perform the actions required by this AD.

FAA's Determination of the Effective Date

Since an unsafe condition exists that requires the immediate adoption of this AD, we have found that notice and opportunity for public comment before issuing this AD are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

Changes to 14 CFR Part 39--Effect on the AD

On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 47998, July 22, 2002), which governs our AD system. This regulation now includes material that relates to special flight permits, alternative methods of compliance, and altered products. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under ADDRESSES. Include "AD Docket No. 2004-NE-05-AD" in the subject line of your comments. If you want us to acknowledge receipt of your mailed comments, send us a self-addressed, stamped postcard with the docket number written on it; we will date-stamp your postcard and mail it back to you. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify it. If a person contacts us verbally, and that contact relates to a substantive part of this AD, we will summarize the contact and place the summary in the docket. We will consider all comments received by the closing date and may amend the AD in light of those comments.

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 with you. You may 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 AD Docket (including any comments and service information), by appointment, between 8:00 a.m. and 4:30 p.m., Monday through Friday, except Federal holidays. See ADDRESSES for the location.

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 the 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. 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. 2004-NE-05-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 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 U.S.C. 106(g), 40113, 44701.

39.13 [Amended]

2. The FAA amends 39.13 by removing Amendment 39-12233 (66 FR 27592, May 18, 2001), and Amendment 39-13016 (68 FR 1519, January 13, 2003), and by adding a new airworthiness directive, Amendment 39-13488, to read as follows: