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GE PROPRIETARY INFORMATION

The information contained in this document is GE proprietary information and is disclosed in

confidence. It is the property of GE and shall not be used, disclosed to others or reproduced

without the express written consent of GE, including, but without limitation, it is not to be used

in the creation, manufacture, development, or derivation of any repairs, modifications, spare

parts, designs, or configuration changes or to obtain FAA or any other government or regulatory

approval to do so. If consent is given for reproduction in whole or in part, this notice and the

notice set forth on each page of this document shall appear in any such reproduction in whole

or in part. The information contained in this document may also be controlled by U.S. export

control laws. Unauthorized export or re-export is prohibited.

All technical documentation and information contained herein, with respect to assembly and disassembly, cleaning, inspection methods and limits, repair methods and limits, operational limits,

life limits and the like, have been developed and approved for use with engines and parts that

have been manufactured and/or approved by GE and that have been maintained in accordance

with GE technical documentation and recommendations. GE has no contractual or legal obligation for, nor knowledge of, non-GE-approved parts and repairs. Accordingly, this document is not

intended to apply to non-GE-approved parts and repairs.

Copyright (2010) General Electric Company, U.S.A.

August 09, 2010 CF6-50 S/B 72-1312

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TRANSMITTAL INFORMATION

REVISION 1 TO SERVICE BULLETIN 72-1312

Revision 1 is issued to update paragraphs 1., PLANNING INFORMATION and 4., APPENDIX - A

INSPECTION PROCEDURE FST PROCEDURE 2075.

The original was issued August 09, 2010. Revision bars in the left margin identify changes.

1. PLANNING INFORMATION

A. Effectivity

CF6-45A/A2

CF6-50A/C/CA/C1/C2/C2B/C2D/C2F/C2R/E/E1/E2

B. Description

This Service Bulletin recommends a one-time on wing ultrasonic inspection (USI) of

the forward spacer arm of the stage 3 low pressure turbine rotor (LPTR) disk.

NOTE: This Service Bulletin is in addition to CF6-50 S/B 72-1307, Revision 01,

that defines the repetitive inspection requirements for the stage 1 and

stage 2 high pressure turbine (HPT) blade airfoils along with

recommendations for performing continuous engine trend monitoring,

troubleshooting, and conditional maintenance checks.

This Service Bulletin is in addition to CF6-50 S/B 72-1313, Revision 01, that

defines an on wing vibration check.

C. Compliance

Category 2

GE recommends that you do this Service Bulletin within 30 days of the issue date of

this Service Bulletin revision unless exempt (see NOTE 1) or already complied with.

NOTE 1: Engines exempt from compliance with this Service Bulletin:

Engines which have complied with CF6-50 S/B 72-1309 after June 03, 2010.

NOTE 2: This Service Bulletin can be accomplished on wing.

This Service Bulletin is offered to improve the reliability or performance of your GE

product, or to help prevent the occurrence of the event or condition described in this

Service Bulletin. If the operator elects not to participate in the bulletin, that decision

will be taken into consideration by GE in evaluating future product performance

issues that may arise in the operator’s fleet.

D. Concurrent Requirements

None.

August 09, 2010 CF6-50 S/B 72-1312

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E. Reason

(1) Objective:

To reduce significant events and stage 3 LPTR disk separations.

(2) Condition:

Cracks have occurred on the inner diameter of the forward spacer arm of the

stage 3 LPTR disk. Cracks gone undetected have led to 360 degree through

cracks and have resulted in uncontained stage 3 LPTR disk separations.

(3) Cause:

A high pressure turbine rotor (HPTR) imbalance that drives an excitation of a

stage 3 LPTR disk-blade mode initiating an indication that could propagate

into a 360 degree through crack that separates the forward spacer arm of the

stage 3 LPTR disk, resulting in an uncontained separation.

(4) Inspection:

This Service Bulletin defines a one-time on wing USI to find a cracked stage 3

LPTR forward spacer arm.

(5) Substantiation:

Substantiation is by analysis and test.

The new USI probe was specifically designed to detect cracks in the forward

spacer arm of the stage 3 LPTR disk. It has been demonstrated and validated

both in the lab and in the field.

F. Approval

This Service Bulletin contains no modification information that revises the approved

configuration and therefore does not require governmental or other regulatory

agency approval.

G. Manpower

After you get access to the stage 3 LPTR disk, you will need approximately 4

man-hours for each engine to do this Service Bulletin.

H. Weight and Balance

Weight and balance are not changed.

I. References (Use the latest version of these documents)

Airbus A300 Aircraft Maintenance Manual (AMM)

Boeing 747 Aircraft Maintenance Manual (AMM)

August 09, 2010 CF6-50 S/B 72-1312

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McDonnell Douglas DC-10-15/DC-10-30 Aircraft Maintenance Manual (AMM)

KC-10 Aircraft Maintenance Manual (AMM)

GEK 50481, CF6-50 Engine Manual (EM)

GEK 28495-2, CF6-50 Illustrated Parts Catalog (IPC)

CF6-50 S/B 72-1307, Revision 01, ENGINE - High Pressure Turbine Rotor (72-53-00) -

Repetitive Engine Maintenance, Inspections and Troubleshooting to Minimize

Stage 1 and Stage 2 HPT Blade Missing Material

CF6-50 S/B 72-1309, ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) -

Stage 3 Low Pressure Turbine Rotor Disk Fluorescent Penetrant Inspection and/or

Ultrasonic Inspection at Shop Visit

CF6-50 S/B 72-1313, Revision 01, ENGINE - Low Pressure Turbine Rotor

(72-00-00) - On Wing Vibration Check

All Operators Wire (AOW), Message Number: 08/CF6/017, Subject: CF6-50

Uncontained Event, July 10, 2008

All Operators Wire (AOW), Message Number: 09/CF6/015, Subject: CF6-50

Uncontained Event, April 3, 2009 GEAE internal use only: CID 457197

All Operators Wire (AOW), Message Number: 09/CF6/030, Subject: CF6-50

Uncontained Event, December 21, 2009

All Operators Wire (AOW), Message Number: 10/CF6/017, Subject: CF6-50

Uncontained Event, July 27, 2010

General Electric Company: Amendment 39-16331. Docket No. FAA-2010-0068;

Directorate Identifier 2010-NE-05-AD; AD 2010-12-10

NOTE: The reference documents listed below are for the engine manufacturer’s

internal use only:

BPP: 10-72-56-04

Field Support Technology (FST) Procedure 2075

J. Publications Affected

None.

K. Interchangeability

Not applicable.

L. Software Accomplishment Summary

Not applicable.

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2. MATERIAL INFORMATION

A. Material - Price and Availability

(1) Parts necessary to do this Service Bulletin:

None.

(2) Other Spare Parts:

None.

(3) Consumables:

Code Number Description

G-33 Laboratory Grade Glycerin/Water Mixture

B. Industry Support Information

None.

C. Configuration Chart

None.

D. Parts Disposition

An unacceptable (reject) USI finding will make the engine unserviceable and require

the replacement of the stage 3 LPTR disk.

E. Tooling - Price and Availability

Tool Part Number Description

GE-FQAP-622 Ultrasonic Inspection Kit

GE Aviation

Quality Technology Center

Attn.: FST Tooling Group

10270 St. Rita Lane

Cincinnati, OH 45215

U.S.A.

Fax: (513) 552-1386

OR

E-mail: ndttooling@ge.com

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NOTE: (1) Due to local shipping restrictions customers might have to obtain item

G-33 from local sources.

To obtain a kit, additional items or replacement tooling, contact Field

Support Technology through one of the following methods. Email

is the preferred method.

E-mail: ndttooling@ae.ge.com

OR

FAX: (513) 552-1386

OR

GE Aviation

Field Support Technology

1 Neumann Way MD Q8

Cincinnati OH 45215

U.S.A.

3. ACCOMPLISHMENT INSTRUCTIONS

A. General

CAUTION: THE ENGINE MUST BE COOLED TO 100 F (37.7 C) DEGREES OR

LESS TO PREVENT PERMANENT DAMAGE TO THE ULTRASONIC

PROBE.

CAUTION: THE PROBES ARE DELICATE INSTRUMENTS. PLEASE HANDLE

WITH CARE.

(1) Prepare the aircraft to provide access to the LPT boroscope plug “B5-3” per

applicable AMM procedure.

(2) Do a USI of the stage 3 LPTR disk to detect flaws in the forward spacer arm.

Refer to APPENDIX A – INSPECTION PROCEDURE FST PROCEDURE

2075.

(3) Replace the engine or return the engine to service per applicable AMM.

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4. APPENDIX A - INSPECTION PROCEDURE FST PROCEDURE 2075

(1) Scope:

(a) The following sections describe the equipment, technique, and procedure

required for conducting an USI of the CF6-50 stage 3 LPTR disk. This

technique should be applied when the engine is fully assembled. The

purpose of this inspection is to detect cracks that may occur in the forward

spacer arm of the stage 3 LPTR disk. Refer to Figure 1 (sheet 1 and 2).

(b) This inspection applies to all CF6-50 stage 3 LPTR disks. Access to the

stage 3 LPTR forward spacer arm is gained through the “B5-3” borescope

port. Refer to Figure 2.

(c) This document describes the general procedure and equipment

approved to accomplish this inspection. For specific cases where the

procedure/equipment described herein cannot be applied in their total

content, specific exceptions should be obtained in writing from GE Aviation.

(2) Applicable Documents:

(a) Appropriate instrument instruction manuals.

(3) Personnel Requirements:

(a) Personnel performing this inspection shall be certified in accordance with

one of the following:

. NAS410

. American Society of Non Destructive Testing (SNT-TC-1A)

. Air Transport Association Specification No. 105 (ATA 105)

. COSAC

. Locally approved certification program.

(b) Personnel that perform this inspection shall receive practical training in the

use of this procedure and must demonstrate proficiency in calibration of the

inspection equipment, inspection of hardware, and evaluation of indications

before the authority to accept and reject hardware is delegated.

(c) Training which may be provided regarding the performance of this inspection

does not imply that the requirements of step 4.(3)(a) have been met.

(4) Equipment Requirements:

(a) The instruments listed in Table 1 are approved for use with this procedure, but

are not supplied with the inspection kit. Contact GE Aviation for information

regarding approval of additional instruments.

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(b) The following items are supplied with USI kit GE-FQAP-622.

ITEM QTY PART NUMBER DESCRIPTION

1 2 389-071-161 Ultrasonic Probe Assembly

2 1 UT-2075 Calibration Standard

3 1 SGP-127 Calibration Standard Holder

4 2 C-012 Coaxial Cable

5 500 ml G-33 Laboratory Grade Glycerin/Water

Mixture (4:1)

6 1 03-409-22C Couplant Dispensing Bottle

7 1 N/A Label

8 1 IM2600 Storm Case w/Foam

9 1 387-008-164 Probe Assembly Guide Tube

(guide tube)

10 1 Q404 Action Marker – Size 33 fine

NOTE: To obtain a USI kit, additional items, or replacement tooling, contact

Field Support Technology. Refer to paragraph 2.E., Tooling - Price and

Availability for contact information.

(5) Pre-Part Inspection Preparation:

(a) Remove the plug at borescope port “B5-3”. Refer to Figure 2.

(b) Perform a visual inspection of the stage 3 LPTR disk forward spacer arm

utilizing a “0 degree” borescope. If there is visual evidence of existing

through wall cracking, this inspection is not required. Refer to step 4.(11) for

disposition.

(c) Reference marks on the inside of the fan case and a stage 1 fan blade will

be used to track the rotation of the stage 3 LPTR disk during inspection.

Place the reference marks as follows:

1 Mark near the leading edge of an arbitrarily chosen stage 1 fan blade

using an approved marker.

2 Make another mark on the inside of the fan case that is in line with the

mark on the fan blade.

NOTE: If there is access to the stage 4 LPT blades through the turbine rear

frame (TRF), this marking technique can be used from the AFT side of

the engine. Reference marks can be placed on the inside of the TRF

and an arbitrarily chosen stage 4 LPT blade.

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(6) Initial Equipment Setup:

(a) Turn the ultrasonic instrument on and allow it to warm up per manufacturers

recommendations or at least 10 minutes.

(b) Adjust the instrument to the initial settings listed in TABLE 1.

(c) Fill the syringe attached to the ultrasonic probe handle with couplant (4 parts

glycerin; 1 part water) in the following manner.

1 Remove the plunger and fill the syringe until it is approximately 3/4 full.

2 Replace the plunger and with the wedge assembly pointing up, depress

the plunger until all trapped air has escaped.

(d) Connect the ultrasonic probe to the ultrasonic instrument with coaxial cable

provided.

(7) System Calibration:

(a) Place the probe on the calibration standard, (Figure 4), so that the probe

cams are seated in the radius from the spacer arm to dovetail posts. Depress

the syringe plunger to apply a small amount of couplant.

(b) Make sure the transducer wedge is seated properly. The wedge is seated

properly when the wedge cams are fully extended, firmly in the radius, and

the wedge is seated firmly to the contour of the calibration standard. Refer

to Figure 5.

(c) Slowly scan the transducer across the calibration standard until the

electrodischarge machining (EDM) Notch is located. While scanning, make

sure the probe cams are firmly seated in the radius. Obtain the peak signal

from the EDM notch.

(d) Observe the instrument display. The first signal at the left side of the

instrument display will be the initial pulse. A second peak signal on the right

side of the display, at approximately 9.0 on the horizontal baseline, will be the

response from the EDM notch. Refer to Figure 6.

(e) Place the initial pulse at 0.0 on the horizontal baseline using the delay control.

(f) Adjust the instrument range control to place the leading edge of the EDM

notch response to 9.0 on the horizontal baseline.

NOTE: If necessary, alternately adjust the delay and range controls to make sure

the initial pulse is at 0.0 and the EDM notch response is at 9.0.

(g) With the delay control only, position the response from the EDM notch to

5.0. Refer to Figure 7.

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(h) Adjust the instrument gain until the response from the EDM notch is set to 80

percent of full screen height (FSH),or the appropriate correction factor.

NOTE: Calibration Standard Correction Factors: As a result of the differences in

the response resulting from possible variations in the fabrication process,

calibration standards may have amplitude correction factors (equivalent

responses) applied to them. The Quality Technology Laboratory will

establish these equivalent responses by comparing the response from the

GE Laboratory Master Standard to the response from each subordinate

standard. In cases where an equivalent response is required, this

equivalent response applies to the calibration only and does alter the

amplitudes specified for indication evaluation.

(i) Scan the transducer across the calibration standard several times to make

sure the peak response is obtained. Make sure the signal is at 80 percent

FSH, or the appropriate correction factor, and at 5.0 on the horizontal

baseline.

(j) Record all calibration data on the inspection data sheet, Form 2075-1.

(8) Hardware Inspection:

(a) Calibrate the equipment in accordance with the calibration section of this

document.

(b) Gain Access to the stage 3 LPTR disk forward spacer arm through borescope

port “B5-3” located at the 4:00 o’clock position aft looking forward (ALF), just

below the split line of the LPT case. Refer to Figure 2.

(c) Insert the guide tube 387-008-164, into the borescope port and turn the

guide until it seats against the outer diameter (OD) of the stage 3 vane. This

creates an insertion path for the transducer wedge.

(d) Rotate the stage 1 fan blades (or stage 4 LPT blades) until the previously

made reference marks are in line. This will be the starting point of the

inspection.

(e) Insert the transducer wedge into the guide tube 387-008-164 as follows.

1 Compress the cams on the transducer wedge so the wedge can be

inserted into the guide tube 387-008-164. Each cam can be compressed

one at a time as they enter the guide tube 387-008-164.

2 When the probe shoe clears the inside of the stage 3 vane shroud the

cams will automatically actuate into the proper position. Make sure the

flat on the probe handle is pointed up. This will position the bend in the

probe stem in the correct position. Angle the probe AFT (handle forward)

until it moves between the trailing edges of the stage 3 vanes.

3 Continue to insert the probe until it touches the stage 3 LPTR forward

spacer arm.

4 At this point, it may be necessary to remove the guide tube 387-008-164.

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5 Actuate the transducer wedge so that it seats properly on the

stage 3 LPTR forward spacer arm. The wedge is fully actuated when the

alignment mark on the probe stem is in line with the outside surface of

the borescope port or guide tube 387-008-164.

(f) Move the transducer wedge AFT (handle forward) until the cams on the

wedge come in contact with the dovetail posts on the stage 3 LPTR disk.

(g) Move the transducer wedge back and forth in the axial direction until both

cams are in contact with the disk posts at the same time. Use slight inward

pressure on the handle to aid in seating the probe properly.

(h) Depress the syringe to apply couplant to the inspection surface. When the

cams are in contact with the disk posts, the flat on the handle is pointed

upward, and there is a front surface signal at approximately 2.0 on the

horizontal baseline, the probe is seated properly. Refer to Figure 8.

CAUTION: THE DESIGN OF THE TRANSDUCER WEDGE CAMS ALLOW FOR

ROTATION OF THE STAGE 3 LPTR DISK IN ONLY ONE DIRECTION

WHILE YOU DO THE SCAN. THE STAGE 3 LPTR DISK SHOULD ALWAYS

BE ROTATED IN THE CLOCKWISE (CW) DIRECTION, ALF. THIS WILL

KEEP THE WEDGE CAMS IN THE FULLY EXTENDED POSITION AND

THE TRANSDUCER WEDGE IN THE PROPER LOCATION.

(i) Starting at the previously marked reference, begin rotation of the stage 3

LPTR disk. Maintain slight pressure on the syringe to keep a continuous

flow of couplant. Scan speed shall not exceed two degree per second. At

this scan speed it should take three minutes for one complete revolution of

the stage 3 LPTR disk.

1 If the stage 1 fan blades are used to rotate the stage 3 LPTR disk, rotate

the fan blades in the counterclockwise (CCW) direction, forward looking

aft (FLA).

2 If the stage 4 LPT blades are used to rotate the stage 3 LPTR disk, rotate

the turbine blades in the CW direction, ALF.

(j) Monitor the instrument display. There should be a small front surface

roll at approximately 2.0 on the horizontal baseline. There should also

be 10 percent to 20 percent background noise between 3.0 and 7.0 of the

instrument display. Refer to Figure 8.

(k) If there is no front surface roll or background noise, the transducer wedge is

not seated properly or there is insufficient couplant. Stop the rotation of the

stage 3 LPTR disk and repeat steps 4.(8)(f) though 4.(8)(j).

NOTE: Indication evaluation should be performed at the time an indication is

observed. Upon completion of any indication evaluation, return the disk to

the area before the evaluation was performed to make sure no area is

missed.

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(l) Monitor the instrument display for any indication equal to or greater than 60

percent FSH between 3.0 and 7.0 on the horizontal baseline. Indications

equal to or greater than 60 percent FSH, shall be evaluated per the indication

evaluation section of this Service Bulletin. Refer to Figure 9.

(m) Continue the inspection for two complete revolutions of the stage 3 LPTR

disk forward spacer arm making sure to overlap the start position to assure

full coverage.

(n) Once complete, remove the transducer assembly from the engine in the

following manner.

NOTE: Alternate lighting may be necessary to aid in probe removal.

1 Remove the guide tube 387-008-164 from the borescope port.

2 Move the transducer wedge away from the dovetail posts and the

stage 3 LPTR disk forward spacer arm.

3 Pull the retractor pull knob on the probe handle. Refer to Figure 3. Turn

the retractor knob CW until it locks in the retracted position. This will place

the probe wedge assembly in the proper alignment to extract the probe.

4 Slowly pull the probe outward until the wedge is up against the inner

borescope port of the stage 3 vane.

5 Visually align the wedge so it can be pulled through the borescope

ports. The probe wedge cams are designed to automatically fold in upon

removal.

(o) Remove any unused couplant from the transducer syringe before storage.

(p) Document the inspection results on the inspection data sheet, Form 2075-1.

(9) Post Calibration:

(a) A calibration check shall be performed upon the completion of each

inspection, whenever any system component or operator is changed, at least

once every hour, or any time the operator suspects a change may have

occurred in the system.

(b) Place the transducer wedge on the calibration standard and depress the

syringe plunger to apply a small amount of couplant.

(c) Make sure the probe shoe is seated properly and scan the transducer wedge

across the calibration standard. Observe the response from the EDM notch.

(d) If the calibration repeats within +/- 10 percent FSH of the initial calibration

amplitude, the test was acceptable.

(e) If the response has decreased by more than 10 percent FSH, the system

must be re-calibrated and hardware inspected since the last acceptable

calibration must be re-inspected.

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(f) If the notch response has increased by more the 10 percent FSH, the system

must be re-calibrated prior to inspection of additional hardware and any

rejected hardware must be re-inspected.

(10) Indication Evaluation:

(a) All indications equal to or greater than 60 percent FSH shall be evaluated.

(b) Any indication should be evaluated at the time it is found. If an indication is

confirmed to be valid, the inspection can be discontinued.

(c) Assure that the calibration amplitude is 80 percent FSH or the appropriate

correction factor. Confirm the EDM notch signal is at 5.0 on the horizontal

baseline.

(d) Reposition the transducer in the suspect area and re-scan.

(e) If the indication is still present and equal to or greater than 60 percent FSH,

the indication is considered valid.

(f) If the indication is not present or less than 60 percent FSH, the indication is

not valid and the indication shall be considered acceptable.

(11) Disposition Criteria:

(a) If there is visual evidence of existing through wall cracking, the disk is not

serviceable and shall be removed from service.

(b) Any stage 3 LPTR disk with an ultrasonic indication that is equal to or greater

than 60 percent FSH between 3.0 and 7.0 on the horizontal baseline shall be

considered rejected by this procedure and removed from service.

(12) Records:

(a) As a minimum, record all requested information on the inspection data sheet,

the LPT Disc/Engine Data Sheet, and forward to the local GE Aviation

representative or directly to GE referencing this Service Bulletin to:

Aviation Operations Center (AOC)

GE Aviation

Subject: CF6-50 S/B 72-1312

One Neumann Way

Cincinnati, OH 45215-1988

U.S.A.

OR

Aviation Operations Center (AOC)

GE Aviation

Subject: CF6-50 S/B 72-1312

FAX: (1-513) 552-3329

OR

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FAX: 1-877-432-3329

E-mail: geae.aoc@ge.com

Subject: CF6-50 S/B 72-1312

TABLE 1 - INITIAL INSTRUMENT SETTINGS

USN58/60

BASIC PLSRCVR

PULSER

RANGE: 0.542 in PULSER: Spike

PROBE DELAY: 0.000 uS ENERGY: High

VELOCITY: 0.1260 in/uS DAMPING: 150 ohms

DISPLAY DELAY: 0.000 uS

RECEIVER

FREQUENCY: 2-25 MHz BB GAIN: 35.0 dB

RECTIFY: Fullwave

DUAL: Off

REJECT: Off / 0 percent

USN52 Series

GAIN: 30.0 dB PULSER: Single

RANGE: 0.542 in. RECTIFY: Full

MATL. VELOCITY: 0.1260 in/uS DAMP: 150 ohms

DELAY: 0.000 uS REJECT: 0 percent

FREQUENCY: 0.4-10 MHz

REP RATE: High

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SONIC 1000 and 1200 Series

PULSE MENU: RANGE MENU:

GAIN: 40.0 dB RANGE: 0.542 in.

PULSE: 50ns DELAY: 0.00 in.

DAMP: 200 ohms VELOCITY: 0.1260 in/us

MODE: Single

VOLTAGE: 150V

RCVR MENU:

DISPLAY: Fullwave

FREQUENCY: 5 MHz

REJECT: 0 percent

USM35

GAIN: 40.0 dB

BASE PULSER

RANGE: 0.542 in DAMPING: LOW

MTL. VELOCITY: 126.0 in/mS POWER: LOW

D-DELAY: 0.000 DUAL: OFF

P-DELAY: 0.000 PRF MODE: 10

RECV

FINE G>: 0

REJECT: 0 percent

FREQUENCY: 0.8 – 8 MHz

RECTIFY: FULL-W

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EPOCH III Model 2300

GAIN: 38.0 dB FULLWAVE: Rectify

REJECT: 0 percent PULSER: Medium

RANGE: 0.542 in DAMPING: 150 ohms

VELOCITY: 0.1260 in/us PULSE-ECHO:

ZERO: 0.000 us

USM25

GAIN 40.0 dB

BASE PULSER

RANGE: 0.542 in DAMPING: High

MTL. VELOCITY: 126.0 in/mS POWER: High

D-DELAY: 0.000 DUAL: OFF

P-DELAY: 0.000 PRF MODE: 10

RECV

FINE G>: 0

REJECT: 0 percent

FREQUENCY: 2.0-20 MHz

RECTIFY: FULL-W

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 16

GE PROPRIETARY INFORMATION - Subject to the restrictions on the cover or first page.
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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Stage 3 LPTR Disc Forward Spacer Arm Initiation Site

Figure 1, ( Sheet 1 of 2 )

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 17

GE PROPRIETARY INFORMATION - Subject to the restrictions on the cover or first page.
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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Stage 3 LPTR Disc Forward Spacer Arm Initiation Site

Figure 1, ( Sheet 2 )

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 18

GE PROPRIETARY INFORMATION - Subject to the restrictions on the cover or first page.
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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Borescope Port “B5-3” Location

Figure 2

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 19

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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Ultrasonic Transducer Assembly

Figure 3

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 20

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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Calibration Standard and Holder

Figure 4

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 21

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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Calibration Technique

Figure 5

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 22

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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Initial Instrument Display

Figure 6

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 23

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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Calibration on the Instrument Display

Figure 7

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 24

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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Proper Coupling on the Instrument Display

Figure 8

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 25

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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Inspection Zone on the Instrument Display

Figure 9

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 26

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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

Form 2075-1 - INSPECTION DATA SHEET

DATE: INSTRUMENT

MODEL:

INSPECTOR: INSTRUMENT S/N:

PROBE P/N: PROBE S/N:

CAL. STD. P/N: CAL. STD. S/N:

FREQUENCY: DAMPING:

GAIN: RECTIFICATION/

DISPLAY:

RANGE: DELAY:

VELOCITY:

Engine S/N: Engine TSN/CSN:

Disc S/N: Disc P/N:

IND. AMP% Baseline

Position

Comments

1

2

3

4

CALIBRATION ______%. POST CALIBRATION ______%

Inspector:

______________________________Date:____________________________

Comments: :

.......................................................................................................................................

.......................................................................................................................................

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 27

GE PROPRIETARY INFORMATION - Subject to the restrictions on the cover or first page.
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ENGINE - Low Pressure Turbine Rotor Assembly (72-57-00) - On Wing Stage 3 LPTR Disk

Ultrasonic Inspection

LPT Disc/Engine Data Sheet

Service provider - who performed the USI

Date of the inspection

Aircraft Tail number

Aircraft Type (e.g. 747, DC10, A300)

Aircraft Total Time (TT) - hours

Aircraft Total Cycles (TC) - cycles

ESN

Engine Position on Aircraft

Engine Time Since New (TSN)

Engine Cycles Since New (CSN)

Engine Time Since Installation (TSI)

Engine Cycles Since Installation (CSI)

Date of last engine shop visit

Engine Time Since Shop Visit (TSV)

Engine Cycles Since Shop Visit (CSV)

LPT S3 Disc Serial Number

LPT S3 Disc Part Number

S3 Disc Total Time

S3 Disc Total Cycles

S3 Disc Total Time Since Installed

S3 Disc Total Cycles Since Installed

Date of last stage 3 LPT disc piece part Shop Visit

S3 Disc Total Time since Last shop visit (FPI)

S3 Disc Total Cycles since last shop visit (FPI)

August 09, 2010 CF6-50 S/B 72-1312

Revision 01, October 18, 2010 PAGE 28

GE PROPRIETARY INFORMATION - Subject to the restrictions on the cover or first page.