ALERT SERVICE BULLETIN

ENGINE — BLADE, LOW PRESSURE TURBINE (LPT) ROTOR, 3RD AND 4TH STAGE —

INSPECTION FOR SHROUD NOTCH WEAR

MODEL APPLICATION

JT8D-209, -217, -217A, -217C, -219

BULLETIN ISSUE SEQUENCE

JT8D Series 72-1518

ATA NUMBER

72-53-00

FAA Airworthiness Directive

Directive No. 2005-02-03

Compliance Category

3

P&W Internal Reference No.

AMP/JFC 94HC165, 96HC145, 98HC608,

00HC035, 99HCD56A, 01HA015C,

01HA015D, 04HA018C, 06HC071

P&W Distribution Code

2627, 2648

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 1 of 14

Printed in United States of America
Summary

Low pressure turbine blade fractures continue to occur and a plan to reduce the probability of

operation with excessively worn blade notches was required. An inspection tool for detecting notch

wear has been released for the standard JT8D Engine in Reference 4, Alert Service Bulletin JT8D

A5913. The torque tool was effective in detecting worn notches and reducing the number of blade

fractures.

Although the procedures released by this Service Bulletin have been effective in other JT8D engine

models, correlation data of notch wear verses torque levels for D-200 engines is very limited and

Pratt & Whitney requests operators’ participation to develop revised limits based on service

experience. Operators who have developed other criteria for inspecting blades for notch wear should

continue their current process in parallel with the new procedures released by this Service Bulletin

until correlation is obtained.

Planning Information

Effectivity Data

Engine Models Applicable

JT8D-209

Engine Serial No. — All Engines

JT8D-217

Engine Serial No. — All Engines

JT8D-217A

Engine Serial No. — All Engines

JT8D-217C

Engine Serial No. — All Engines

JT8D-219

Engine Serial No. — All Engines

NOTE: The notation “All Engines” applied to an engine model indicates that these engine

models are no longer being manufactured. This Service Bulletin is applicable to all

of the engines in that model.

Concurrent Requirements

There are no concurrent requirements.

Reason

1. Problem: Excessively worn LPT blade notches can result in high cycle fatigue (HCF)

fractures of the blade and engine in flight shutdowns.

2. Cause: Normal engine operating stresses produce wear to the cross-notch hardface

surfaces, resulting in reduced blade vibration damping and changes to vibratory modes.

Excessively worn notch surfaces result in increased blade operating stresses that can

cause high cycle fatigue fractures of the blade.

3. Solution: To provide a periodic inspection program for detecting excessively worn LPT

blade notches and reduce the probability of blade fractures.

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 2
Description

Perform an inspection of the 3rd and 4th Stage Turbine Blades for the JT8D-209, -217,

-217A models and for the 4th Stage Turbine Blades for the JT8D-217C and 219 models.

Compliance

Category 3

The time intervals listed in this Service Bulletin are based on limited service data. Operators

who have established other time intervals based on their experience should continue to use

their criteria until field experience provides revised limits.

NOTE: An alternate method of compliance (AMOC) to AD 2005-02-03 must be approved

by the FAA or local authority if other criteria or time intervals are used.

PART 1: JT8D-209, -217, -217A ENGINES

(1) Do the Pre Service Bulletin JT8D 5867 (small notch) 3rd Turbine Blade

inspection in 6,000 hours since the installation of new blades or by 4,000

hours since installation of refurbished blades. Inspect again by the

Accomplishment Instructions.

OR

(2) Do the Post Service Bulletin JT8D 5867 (large notch) 3rd Stage Turbine

Blades by 10,000 hours since installation of new blades, or by 7,000

hours since installation of refurbished blades

AND

(3) Do the Pre Service Bulletin JT8D 6029 (small notch) 4th Stage Turbine

Blades by 6,000 hours since installation of new blades, or by 4,000

hours since installation of refurbished blades.

OR

(4) Do the Post Service Bulletin JT8D 6029 or JT8D 6308 (large notch) 4th

Stage Turbine Blades by 10,000 hours since installation of new blades,

or by 7,000 hours since installation of refurbished blades.

PART 2: JT8D-217C, -219 ENGINES

(1) Do the Pre Service Bulletin JT8D 6090 (small notch) 4th Stage Turbine

Blades by 5,000 hours since installation of new blades, or by 4,000

hours since installation of refurbished blades.

OR

(2) Do the Post Service Bulletin JT8D 6090 or JT8D 6402 or JT8D 6412

(large notch) 4th Stage Turbine Blades by 10,000 hours since installation

of new blades, or by 7,000 hours since installation of refurbished

“As-Cast” blades, or by 4,000 hours since installation of refurbished

“Modified” blades.

Approval Data

The times between inspections specified in the Compliance section and the inspection

procedures specified in the Accomplishment Instructions agree with the applicable Federal

Aviation Regulations and are FAA-Approved for the engine model(s) given.

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 3
Revision 6 to this Service Bulletin is approved by the Manager, Engine Certification Office,

ANE-140, by letters dated September 14, 2006 and February 14, 2007 as an Alternate

Method Of Compliance (AMOC) to Reference 11, Airworthiness Directive No. 2005-02-03,

by replacing earlier revisions of the Service Bulletin as referenced in the Airworthiness

Directive.

Manpower

The estimate of man-hours of labor directly necessary to do the intent of this Service

Bulletin are as follows:

1. Replacement Requirements................................................ Not Applicable.

2. Other Items that are Necessary (Inspection of 3rd or 4th Stage Turbine Blades

per NDIP-662)............................................................................... 1.0

3. Total Necessary Man-hours ............................................................... 1.0

Weight Data

No Change.

Electrical Load Data

Not Applicable.

Software Accomplishment Summary

Not Applicable.

References

1. Turbojet Engine Standard Practices Manual, Part No. 585005.

2. JT8D-200 Illustrated Parts Catalog, Part No. 773129.

3. JT8D-200 Engine Manual, Part No. 773128.

4. Service Bulletin No. JT8D 5867; Engine — Blade, Turbine Rotor, 3rd Stage — Replacement

of Featuring An Increased Platform Notch Contact Area. Issue Sequence 72-1367, JT8D

Series.

5. Alert Service Bulletin No. JT8D A5913; Engine — Blade, Turbine Rotor, 3rd and 4th Stage

— Uncontained Blade Fracture Management. Issue Sequence A72-1386, JT8D Series.

6. Service Bulletin No. JT8D 6029; Engine — Blade, Turbine Rotor, Fourth Stage —

Replacement of. Issue Sequence 72-1430, JT8D Series.

7. Service Bulletin No. JT8D 6090; Engine — 4th Stage Turbine — Modified To Increase

Shroud Notch Contact Area. Issue Sequence 72-1430, JT8D Series.

8. Service Bulletin No. JT8D 6308; Engine — Blade, Turbine Rotor, Fourth Stage —

Replacement Of. Issue Sequence 72-1558, JT8D Series.

9. Service Bulletin No. JT8D 6402; Engine — 4th Stage Blade, Low Pressure Turbine — Shot

Peening Of Shroud-To-Airfoil Fillet Radius. Issue Sequence 72-1603, JT8D Series.

10. Service Bulletin No. JT8D 6412; Engine — Blade, Low Pressure Turbine (LPT), 4th Stage

— Replacement Of. Issue Sequence 72-1607, JT8D Series.

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 4
11. Airworthiness Directive No. 2005-02-03.

12. NDIP-662, Revision E dated November 14, 2006; JT8D-200, 3rd and 4th Stage LPT Blade

Shroud Cross Notch Wear Mechanical Inspection (Assembled/Aircraft Installed).

13. Special Instruction 80F-00; Engine — Front Compressor Rotor And Stator Assembly, 2nd,

3rd And 4th Stage Low Pressure Turbine Blades — Provide A Modification Procedure To

Incorporate Specification PWA 36110 Cobalt Base Alloy Coating (Tribaloy T800).

NOTE: References 4, thru 10, and 13, are shown to help find configurations in relation to

this bulletin.

Publications Changed

See the Material Information Part Number Instruction — Disposition codes for cleaning,

inspection and repair compatibility between the new and old part number(s).

JT8D-200 Illustrated Parts Catalog, Part No. 773129

72-53-00, Figure 3

JT8D-200 Engine Manual, Part No. 773128

72-53-11

72-53-12

72-53-13

Interchangeability

Not Applicable.

Information in the Appendix

Alternate Accomplishment Instructions (No)

Progression Charts (No)

Added Data (Yes)

Revision to Table of Limits (No)

Inspection Procedures (Yes)

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 5
Material Information

Material — Cost and Availability

1. There is no new material cost to do this Service Bulletin if parts do not need to be replaced.

2. Part prices were not available at the time of Service Bulletin publication. Contact Pratt &

Whitney Spares Management & Logistics for firm quotations.

3. There is no kit provided to do this Service Bulletin.

4. Part availability information is provided in material data Instructions — Disposition.

Industry Support Program

Not Applicable.

The material data that follows is for each engine.

NOTE: It is possible to use the Chapter/Section and Figure/Item reference number shown

below the old part number to find the part in the Illustrated Parts Catalog.

The material data that follows is for each engine.

NOTE: All existing 3rd and 4th stage turbine blades must be inspected per the

Accomplishment Instructions of this Service Bulletin. The following list of blade part

numbers is provided for the Part Number vs. Service Bulletin index. If any 3rd or

4th stage turbine blades are found which are not listed below, those must also be

inspected. Contact your technical support engineer to have those part numbers

added to the list below.

For JT8D-209, -217, -217A, -217C, -219 Engines:

New PN Qty Estimate of Unit

Price ($)

Keyword Old PN Instructions —

Disposition

88 BLADE —

TURBINE

ROTOR, 3 STG

772203

(72-53-00-3-10)

(3)(N)

803003 88 959.00 BLADE —

TURBINE

ROTOR, 3 STG

803003

(72-53-00-3-10 B)

(3)(A)

58 BLADE —

TURBINE

ROTOR, 4 STG

775404

(72-53-00-3-40)

(3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

798404

(72-53-00-3-40 A)

(3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

804304

(72-53-00-3-40 B)

(3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

810504 (3)(N)

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 6
New PN Qty Estimate of Unit

Price ($)

Keyword Old PN Instructions —

Disposition

58 BLADE —

TURBINE

ROTOR, 4 STG

810504-001 (3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

808904

(72-53-00-3-40 C)

(3)(N)

851704 58 1,047.00 BLADE —

TURBINE

ROTOR, 4 STG

851704

(72-53-00-3-40)

(3)(A)

58 BLADE —

TURBINE

ROTOR, 4 STG

821524

(72-53-00-3-40 E)

(3)(N)

822504 58 1,064.00 BLADE —

TURBINE

ROTOR, 4 STG

822504

(72-53-00-3-40 F)

(3)(A)

58 BLADE —

TURBINE

ROTOR, 4 STG

808904-001

(72-53-00-3-40AA)

(3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

819104

(72-53-00-3-40AB)

(3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

819204

(72-53-00-3-40AC)

(3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

819104-001

(72-53-00-3-40AD)

(3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

819204-001

(72-53-00-3-40AE)

(3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

821204 (3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

821304 (3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

821404 (3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

821204-001 (3)(N)

58 BLADE —

TURBINE

ROTOR, 4 STG

821304-001 (3)(N)

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 7
New PN Qty Estimate of Unit

Price ($)

Keyword Old PN Instructions —

Disposition

58 BLADE —

TURBINE

ROTOR, 4 STG

821404-001 (3)(N)

Modification and Spares Information

Estimated part prices are provided when they are available at time of publication. The

Estimate of Unit Price is only for planning purposes and does not constitute a firm

quotation. An asterisk (*) is shown where part pricing information was unavailable. In either

case, contact Pratt & Whitney Spares Management & Logistics for firm quotations.

Parts Modification Conditions

(3) Inspect per the Accomplishment Instructions

Spare Parts Availability

(A) The new part is available.

(N) The old part is not available. See Reference 2., Illustrated Parts Catalog, for

applicable replacement blades.

Cleaning, Inspection and Repair Information

Not Applicable.

Vendor Services or Special Components/Materials

Not Applicable.

Material Data for Each Spare Engine

The material for each spare engine is as stated in the preceding material information

section.

Reidentified Parts

Not Applicable.

Necessary Tools

New Support Equipment that is necessary

Tool No. Name Manufacturer Design

Availability

Date

Aperture

Card

Delivery

Date

PWA 104224 Mechanical

Inspection Tool

System

Pratt & Whitney

(See NDIP-662 in

the Appendix)

PWA 107309 Notch Guage

Support Fixture

Pratt & Whitney

(See NDIP-662 in

the Appendix)

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 8
Support Equipment available before

Tool No. Name Manufacturer

LD 3403 Mechanical Inspection Tool

System

No longer Available. Repairs

to be submitted to Pratt &

Whitney (See NDIP-662 in

the Appendix)

NOTE: A periodic check of the length of the “T” or the “L” end gages, for the 3rd and the

4th stage tools respectively, and of the torque limiting screwdriver must be done

periodically or if damage occurs to assure inspection reliability. Refer to NDIP-662

in the Appendix for the inspection interval and repair limits.

NOTE: Tool systems LD 3403 and PWA 104224 can be used interchangeably. The

LD 3403 tool system may still be used for inspection of the 3rd and 4th stage LPT

blades until new tooling is needed. Refer to NDIP-662 in the Appendix for the

inspection interval and repair limits.

NOTE: EXCEPT FOR WORK OR SUPPLIES TO BE PERFORMED OR FURNISHED BY

PRATT & WHITNEY, IT IS UNDERSTOOD THAT PRATT & WHITNEY DOES NOT

ENDORSE THE WORK PERFORMED BY THE COMPANY OR COMPANIES

NAMED HEREIN OR ANY OTHER COMPANY AND DOES NOT ACCEPT

RESPONSIBILITY TO ANY DEGREE FOR THE SELECTION OF SUCH

COMPANY OR COMPANIES FOR THE PERFORMANCE OF ANY WORK OR

PROCUREMENT OF SUPPLIES.

Other Material Information Data

Not Applicable.

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 9
Accomplishment Instructions

Part 1: JT8D-209, 217, 217A Engines

NOTE: These inspections are only to be performed on engines that are installed (on-wing)

with the blades undisturbed following engine run.

1. Do the inspection procedure as specified in the Appendix (NDIP-662), at the intervals

specified below.

A. Do the first inspection of the pre Service Bulletin JT8D 5867 (small notch) 3rd Stage

Turbine Blades by 6000 hours since installation of new blades, or by 4000 hours since

installation of refurbished blades.

OR

Do the first inspection of the post Service Bulletin JT8D 5867 (large notch) 3rd Stage

Turbine Blades by 10,000 hours since installation of new blades, or by 7,000 hours

since installation of refurbished blades.

B. Do the first inspection of the pre Service Bulletin JT8D 6029 (small notch) 4th Stage

Turbine Blades by 6,000 hours since installation of new blades, or by 4,000 hours

since installation of refurbished blades.

OR

Do the first inspection of the post Service Bulletin JT8D 6029 or JT8D 6308 (large

notch) 4th Stage Turbine Blades by 10,000 hours since installation of new blades, or

by 7,000 hours since installation of refurbished blades.

C. Inspect again at the applicable interval for the results that you found during the first

inspection. Refer to Table 1 and Table 2 for the applicable interval.

NOTE: The subsequent inspection interval must not be greater than the previous

inspection interval.

TABLE 1 — REINSPECTION INTERVAL FOR ALL 3RD STAGE BLADES

NO. OF READINGS TORQUE READINGS LIMIT

All Greater than or equal to

15 lb-in (1.695 N.m)

Inspect again within

1000 hours

1 or more Less than 15 lb-in

(1.695 N.m) but Greater

than or equal to 10 lb-in

(1.130 N.m)

Inspect again within

500 hours

1 to 3 Less than 10 lb-in

(1.130 N.m) but Greater

than or equal to 5 lb-in

(0.565 N.m)

Inspect again within

125 hours

4 or more Less than 10 lb-in

(1.130 N.m) but Greater

than or equal to 5 lb-in

(0.565 N.m)

Remove engine

within 20 hours

1 or more Less than 5 lb-in

(0.565 N.m)

Remove engine

within 20 hours

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 10
TABLE 2 — REINSPECTION INTERVAL FOR ALL 4TH STAGE BLADES

NO. OF READINGS TORQUE READINGS LIMIT

All Greater than or equal to

15 lb-in (1.695 N.m)

Inspect again within

1,000 hours

1 or more Less than 15 lb-in

(1.695 N.m) but Greater

than or equal to 10 lb-in

(1.130 N.m)

Inspect again within

500 hours

1 to 6 Less than 10 lb-in

(1.130 N.m) but Greater

than or equal to 5 lb-in

(0.565 N.m)

Inspect again within

125 hours

7 or more Less than 10 lb-in

(1.130 N.m) but Greater

than or equal to 5 lb-in

(0.565 N.m)

Remove engine

within 20 hours

1 or more Less than 5 lb-in

(0.565 N.m)

Remove engine

within 20 hours

2. The initial inspection or the reinspection intervals should not be reset unless the blades are

refurbished. Whenever a used (service run) blade is reinstalled in a rotor, the previous

used time should be subtracted from the initial inspection threshold.

NOTE: For the purpose of this inspection, refurbishment is defined as restoration of

either the shrouds or blade pretwist or both, per Reference 3, Engine Manual.

3. Whenever a refurbished or used blade is intermixed with new blades in a rotor, use the

lowest initial inspection threshold that is applicable.

4. Pratt & Whitney recommends that all turbine stages (2nd, 3rd, and 4th) be removed and all

blades detail inspected, as specified in Reference 3, Engine Manual, Chapter/Section

72-53-11 thru 72-53-13, whenever one stage fails inspection per this Service Bulletin.

5. Request that operator data be provided (optional) as follows:

The procedures released for these engine models have been demonstrated to be effective

for other similar engines, however, the correlation data for the torque levels versus blade

notch wear is very limited at this time and Pratt & Whitney requests operator participation

to develop limits based on service hardware and operator experience. The time limits

versus torque levels are based on limited data and will be revised or confirmed by industry

data or experience. Forward the requested information to the local P&W Field

Representative.

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 11
Part 2: JT8D-217C, -219 Engines

NOTE: These inspections are only to be performed on engines that are installed (on-wing)

with the blades undisturbed following engine run.

1. Do the inspection procedure as specified in Appendix (NDIP-662), at the intervals specified

below.

A. Do the first inspection of the pre Service Bulletin JT8D 6090 (small notch) 4th Stage

Turbine Blades by 5000 hours since installation of new blades, or by 4000 hours since

installation of refurbished blades.

OR

Do the first inspection of the post Service Bulletin JT8D 6090 or JT8D 6402 or

JT8D 6412 (large notch) 4th Stage Turbine Blades by 10,000 hours since installation

of new blades, or by 7,000 hours since installation of refurbished “As-Cast” blades, or

by 4,000 hours since installation of refurbished “Modified” blades.

NOTE: “As-Cast” refers to blades that were machined from new castings and

“Modified” refers to blades that were derived from the pre Service Bulletin

JT8D 6090 configuration. See Reference 7, Service Bulletin JT8D 6090,

Figure A, to identify the type and part number of blades.

B. Inspect again at the applicable interval for the results that you found during the first

inspection. Refer to Table 3 for the applicable interval.

NOTE: The subsequent inspection interval must not be greater than the previous

inspection interval.

TABLE 3 — REINSPECTION INTERVAL FOR ALL 4TH STAGE BLADES

NO. OF READINGS TORQUE READINGS LIMIT

All Greater than or equal to

15 lb-in (1.695 N.m)

Inspect again within

1,000 hours

1 or more Less than 15 lb-in

(1.695 N.m) but Greater

than or equal to 10 lb-in

(1.130 N.m)

Inspect again within

500 hours

1 to 6 Less than 10 lb-in

(1.130 N.m) but Greater

than or equal to 5 lb-in

(0.565 N.m)

Inspect again within

125 hours

7 or more Less than 10 lb-in

(1.130 N.m) but Greater

than or equal to 5 lb-in

(0.565 N.m)

Remove engine

within 20 hours

1 or more Less than 5 lb-in

(0.565 N.m)

Remove engine

within 20 hours

2. The intial inspection or the reinspection intervals should not be reset unless the blades are

refurbished. Whenever a used (service run) blade is reinstalled in a rotor, the previous

used time should be subtracted from the initial inspection threshold.

NOTE: For the purpose of this inspection, refurbishment is defined as restoration of

either the shrouds or blade pretwist or both, per Reference 3, Engine Manual.

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 12
3. Whenever a refurbished or used blade is intermixed with new blades in a rotor, use the

lowest initial inspection threshold that is applicable.

4. Pratt & Whitney recommends that all turbine stages (2nd, 3rd, and 4th) be removed and all

blades detail inspected, as specified in Reference 3, Engine Manual, Chapter/Section

72-53-11 thru 72-53-13, whenever one stage fails inspection per this Service Bulletin.

5. Request that operator data be provided (optional) as follows:

The procedures released for these engine models have been demonstrated to be effective

for other similar engines, however, the correlation data for the torque levels versus blade

notch wear is very limited at this time and Pratt & Whitney requests operator participation

to develop limits based on service hardware and operator experience. The time limits

versus torque levels are based on limited data and will be revised or confirmed by industry

data or experience. Forward the requested information to the local P&W Field

Representative.

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 13
Appendix

Added Data

Number values shown in parentheses adjacent to U.S. values are International System of units

(SI) equivalents.

To calculate part life, include the hours and/or cycles since the part was made. Use the total

hours or cycles to calculate life limits that are the result of part modification, a part used in an

engine with different thrust, or for some other reason.

Inspection Procedures

NDIP-662, Revision E follows:

October 12/95

REVISION NO. 6 - May 3/07

JT8D A6224

Page 14

JT8D-200

3rd and 4th Stage LPT Blade

Shroud Cross Notch Wear

Mechanical Inspection

(Assembled/Aircraft Installed)

NDIP-662

Revision E

November 14, 2006

Instructions Described Within This Procedure

Do Not Replace, Amend or Supersede Any

Instructions Included in Other Pratt & Whitney

Technical Publications.

Active Service Bulletins And Other Technical

Publications Issued by Pratt & Whitney Reflect

Official Company Procedures and Policies.
JT8D-200

3rd and 4th Stage LPT Blade

Shroud Cross Notch Wear

Mechanical Inspection

(Assembled/Aircraft Installed)

I. GENERAL

The objective of this mechanical inspection (torque test) is to detect excessive

shroud cross notch wear of the 3rd stage low pressure turbine (LPT) blades for

the JT8D-209, -217, and -217A engine models and of the 4th stage LPT blades

for the JT8D-209, -217, -217A, -217C, and -219 engine models.

The inspection is accomplished using a mechanical tool made up of a torque

screwdriver, notch gauge, and notch gauge support. The tool is inserted through

the tailpipe and placed between two adjacent LPT blades within the same stage

LPT rotor. The tool is rotated through the torque screwdriver in an attempt to

separate the blades and qualitatively determine the tightness or looseness of the

rotor. Three (3) torque settings — 15 inch-pounds, 10 inch-pounds, and 5

inch-pounds — are defined and the setting versus results are recorded. The

inspection must be conducted on the 3rd stage LPT at fourteen (14) inspection

locations. Since it is not possible for the inspector to see the number of 3rd stage

blades that are passing between each inspection location as the rotor is turned,

the inspector must count the number of 4th stage blades that pass between

each inspection location. For the purpose of the 3rd stage blade inspection, this

equates to approximately every 4th stage blade. The inspection must also be

conducted on the 4th stage LPT at twenty-nine (29) inspection locations. For the

purpose of the 4th stage blade inspection, this equates to every other 4th stage

blade around the rotor. There are eighty-eight (88) 3rd stage blades and

fifty-eight (58) 4th stage blades.

The purpose of Revision A was to update tooling requirements and to include

minor editorial changes.

The purpose of Revision B was to include instructions for inspection of the 4th

stage LPT blade for the JT8D-209, -217, and -217A engine models and to

include minor editorial changes.

NDIP-662

Revision E

1
The purpose of Revision C was to:

• inform operators of the requirement to contact Pratt & Whitney for procurement

and repair of the tooling for this inspection;

• add PWA tool numbers;

• detail changes incorporated into the 4th stage LPT blade notch gauge for the

JT8D-217C and -219 engine models based on recent correlation of data

between the mechanical inspection conducted on assembled/aircraft installed

blades and shroud cross notch wear dimensional inspections of corresponding

disassembled blades;

• describe the equivalency between the PWA tool numbers and tooling originally

obtained through Leeward Consultants;

• add revised notch gauge repair limits;

• revise the “T” end nomenclature to ”L” end for the 4th stage LPT blade notch

gauges to more accurately describe the notch gage;

• revise and add figures to clarify the tooling and application of the 4th stage

LPT blade notch gauges; and

• upgrade the instruction manual to an electronic format.

The purpose of Revision D is to increase the number of inspection locations for

the 4th stage blade from 14 to 29 locations.

The purpose of Revision E is to add the PWA 107309 4th stage LPT gauge

support to the procedure and to make minor editorial changes.

This manual is provided as an inspection training guide. Refer to the latest

revision of Alert Service Bulletin A6224 for current requirements.

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II. ACCOMPLISHMENT INSTRUCTIONS

A. EQUIPMENT REQUIRED

1. PWA 104224, Mechanical Inspection Tool System, Figure 1, consisting

of the following:

FIGURE 1

PWA 104224 MECHANICAL INSPECTION TOOL SYSTEM (Excluding PWA 107309

Notch Gauge Support)

a. PWA 104225, 3rd Stage LPT Blade Notch Gauge — JT8D-209,

-217, and -217A Models.

CAUTION: A PERIODIC CHECK OF THE LENGTH OF THE

“T” END OF THE PWA 104225 3RD STAGE LPT

BLADE NOTCH GAUGE SHOULD BE DONE

SEMI-ANNUALLY OR ANNUALLY, OR IF DAMAGE

OCCURS TO THE TOOL, TO ASSURE

INSPECTION RELIABILITY, FIGURE 2.

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FIGURE 2

MINIMUM ALLOWABLE LENGTH OF “T” END OF THE PWA 104225 3RD STAGE LPT

BLADE NOTCH GAUGE

CAUTION: IF THE MINIMUM LENGTH DIMENSION FOR THE “T” END OF THE PWA

104225 NOTCH GAUGE IS LESS THAN 1.035 (26.29 MM), THE NOTCH

GAUGE MUST BE SUBMITTED TO PRATT & WHITNEY FOR REPAIR.

b. PWA 104226, 4th Stage LPT Blade Notch Gauge — JT8D-217C,

and -219 Models.

CAUTION: A PERIODIC CHECK OF THE LENGTH OF THE “L”

END OF THE PWA 104226 4TH STAGE LPT

BLADE NOTCH GAUGE SHOULD BE DONE

SEMI-ANNUALLY OR ANNUALLY, OR IF DAMAGE

OCCURS TO THE TOOL, TO ASSURE

INSPECTION RELIABILITY, FIGURE 3.

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FIGURE 3

MINIMUM ALLOWABLE LENGTH OF “L” END OF THE PWA 104226 4TH STAGE LPT

BLADE NOTCH GAUGE

CAUTION: IF THE MINIMUM LENGTH DIMENSION FOR THE “L” END OF THE PWA

104226 NOTCH GAUGE IS 1.755 INCHES (44.58 MM), THE NOTCH

GAUGE MUST BE SUBMITTED TO PRATT & WHITNEY FOR REPAIR.

NOTE: The design of the PWA 104226 4th stage LPT blade

notch gauge has been modified from the original design

of the LD 403 notch gauge, Figure 4.

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FIGURE 4

COMPARISON OF “L” END OF PWA 104226 AND LD 403 4TH STAGE LPT BLADE

NOTCH GAUGE — JT8D-217C AND -219 ENGINE MODELS

The modifications include:

• re-design of the “L” end to a design similar to the PWA 104227

4th stage LPT blade notch gauge;

• increase of the length dimension of the “L” end based on recent

acquisition of correlation data between the mechanical

inspection conducted on assembled/aircraft installed blades

and shroud cross notch wear dimensional inspections of

disassembled blades;

• re-design of the attachment details for the roller to eliminate the

retaining clip (Circlip) and increase the attachment durability;

and

• incorporate the same attachment details for the wheel as the

PWA 104227 4th stage LPT blade notch gauge.

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c. PWA 104227, 4th Stage LPT Blade Notch Gauge — JT8D-209,

217, and -217A Models.

CAUTION: A PERIODIC CHECK OF THE LENGTH OF THE “L”

END OF THE PWA 104227 4TH STAGE LPT

BLADE NOTCH GAUGE SHOULD BE DONE

SEMI-ANNUALLY OR ANNUALLY, OR IF DAMAGE

OCCURS TO THE TOOL, TO ASSURE

INSPECTION RELIABILITY, FIGURE 5.

FIGURE 5

MINIMUM ALLOWABLE LENGTH OF “L” END OF THE PWA 104227 4TH STAGE LPT

BLADE NOTCH GAUGE

CAUTION: IF THE MINIMUM LENGTH DIMENSION FOR THE “L” END OF THE PWA

104227 NOTCH GAUGE IS 1.665 INCHES (42.29 MM), THE NOTCH

GAUGE MUST BE SUBMITTED TO PRATT & WHITNEY FOR REPAIR.

NOTE: The design of the PWA 104227 4th stage LPT blade

notch gauge has been modified slightly from the original

design of the LD 405 notch gauge.

The modification incorporates the re-design of the

attachment details for the roller to eliminate the retaining

clip (Circlip) and increase the attachment durability.

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d. PWA 104223, Extension Tool — Quantity of 1 required, Figure 6.

FIGURE 6

PWA 104223 EXTENSION TOOL

NOTE: One (1) PWA 104223 extension tool is required for

inspection of the 3rd and 4th stage LPT blades.

The extension tool has been integrated into one design

for use between the JT8D engine models (NDIP-665)

and the JT8D-200 engine models (NDIP-662).

e. PWA 107309 Notch Gauge Support - Engine Assembly, LPT 4th

Stage Blade Inspection. See Figure 12 Sheet 1.

f. Torque Limiting Screwdriver, Adjustable, Sturtevant Richmont

P/N CAL-36/4 or equivalent.

NOTE: Depending on usage, Sturtevant Richmont recommends

a 6-month to one-year interval for re-certification of the

torque limiting screwdriver. For repair or certification, the

torque limiting screwdriver should be returned to:

Sturtevant Richmont

Torque Measurement Systems

Division of Ryeson Corporation

3203 North Wolf Road

Franklin Park, IL 60131

U.S.A.

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g. Hex Screwdriver, 3-32.

NOTE: The LD 3403 mechanical inspection tool system originally

obtained through Leeward Consultants may still be used for

inspection of the 3rd and 4th stage LPT blades until new

tooling is needed.

The LD 3403 mechanical inspection tool system consists of:

• one (1) LD 303 3rd stage LPT blade notch gauge for the JT8D-209,

-217, and -217A engine models;

CAUTION: A PERIODIC CHECK OF THE LENGTH OF THE “T”

END OF THE LD 303 3RD STAGE LPT BLADE

NOTCH GAUGE SHOULD BE DONE

SEMI-ANNUALLY OR ANNUALLY, OR IF DAMAGE

OCCURS TO THE TOOL TO ASSURE INSPECTION

RELIABILITY, REFER TO FIGURE 2.

IF THE MINIMUM LENGTH DIMENSION FOR THE “T”

END OF THE LD 303 NOTCH GAUGE IS LESS THAN

1.035 (26.29 MM), THE NOTCH GAUGE MUST BE

SUBMITTED TO PRATT & WHITNEY FOR REPAIR.

• one (1) LD 403 4th stage LPT blade notch gauge for the JT8D-217C

and -219 engine models;

CAUTION: A PERIODIC CHECK OF THE LENGTH OF THE “L”

END OF THE LD 403 4TH STAGE LPT BLADE

NOTCH GAUGE SHOULD BE DONE

SEMI-ANNUALLY OR ANNUALLY, OR IF DAMAGE

OCCURS TO THE TOOL, TO ASSURE INSPECTION

RELIABILITY, REFER TO FIGURE 4.

IF THE MINIMUM LENGTH DIMENSION FOR THE “L”

END OF THE LD 403 NOTCH GAUGE IS LESS THAN

1.695 (43.05 MM), THE NOTCH GAUGE MUST BE

SUBMITTED TO PRATT & WHITNEY FOR REPAIR.

• one (1) LD 405 4th stage LPT blade notch gauge for the JT8D-209,

-217, and -217A engine models;

CAUTION: A PERIODIC CHECK OF THE LENGTH OF THE “L”

END OF THE LD 405 4TH STAGE LPT BLADE

NOTCH GAUGE SHOULD BE DONE

SEMI-ANNUALLY OR ANNUALLY, OR IF DAMAGE

OCCURS TO THE TOOL, TO ASSURE INSPECTION

RELIABILITY, REFER TO FIGURE 5.

IF THE MINIMUM LENGTH DIMENSION FOR THE “L”

END OF THE LD 405 NOTCH GAUGE IS LESS THAN

1.665 (42.29 MM), THE NOTCH GAUGE MUST BE

SUBMITTED TO PRATT & WHITNEY FOR REPAIR.

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• one (1) LD 3404 or LD 3405 extension tool;

• one (1) torque limiting screwdriver, Sturtevant Richmont P/N

CAL-34/6; and

• one (1) 3-32 allen wrench.

The LD 403 can be modified to increase the dimension of the “L” end

and become equivalent to the dimensional requirements of the PWA

104226 4th stage LPT blade notch gauge. This modification can/will

be incorporated during the next repair of the LD 403 notch gauge. The

LD 403 must be in good condition to incorporate this modification;

presence of damage to the shaft, or other details may require the

procurement of the PWA 104226 notch gauge.

The LD 405 can be modified to incorporate the re-designed

attachment details. The LD 405 must be in good condition to

incorporate this modification; presence of damage to the shaft, or

other details may require the procurement of the PWA 104227 notch

gauge.

The LD 3403 mechanical inspection tool system details must be

submitted to Pratt & Whitney for repair.

2. Marking Pencil, as required per Standard Practices Manual 70-11.

NOTE: The marking pencil must be attached to an extension tool

long enough to allow marking on the convex side of the 4th

stage LPT blades during inspection.

3. Vernier Calipers, capable of measuring up to 2.0 inches (50.8 mm).

4. Light Source, capable of providing adequate lighting within the tailpipe

to the inspection area.

5. Coverall Clothing.

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B. AIRFRAME/ENGINE PREPARATION

CAUTION: THIS INSPECTION IS CONDUCTED WITHIN THE TAILPIPE

ON AN ASSEMBLED ENGINE WHICH HAS BEEN

OPERATED AND APPLIES TO AN AIRCRAFT INSTALLED

ENGINE.

EVERY PRECAUTION MUST BE TAKEN TO INSURE THE

INSPECTION IS CONDUCTED IN A SAFE MANNER TO

PREVENT ACCIDENT OR INJURY.

INSURE THE THRUST REVERSER IS INOPERABLE

BEFORE PROCEEDING WITH THIS INSPECTION. ATTACH

WARNING TAG TO STARTER AND REVERSER OVERRIDE

SWITCH.

THE ENGINE MUST COOL DOWN SUFFICIENTLY TO

ALLOW THE INSPECTOR TO SAFELY ENTER THE

EXHAUST DUCT. A MINIMUM COOL DOWN TIME IS

TYPICALLY 2 TO 4 HOURS.

NOTE: It is important to conduct the inspection on an engine within a

consistent temperature range within the LPT area. This will

minimize any significant deviations in inspection results from one

inspection on the engine to another.

1. Position the light source to provide adequate lighting to the inspection

area within the tailpipe.

2. Rotate the LPT rotor until an access window is located in the bottom

quadrant nearest the 6 o’clock position (as viewed clockwise from the

rear with 12 o’clock at the top of the engine), Figure 7.

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FIGURE 7

INSPECTION ACCESS AREA

CAUTION: IT IS IMPORTANT THAT THE ACCESS WINDOW BE LOCATED IN THE

BOTTOM QUADRANT NEAREST THE 6 O’CLOCK POSITION OF THE

ENGINE FOR CONSISTENCY IN OVERALL FLEET INFORMATION.

a. For inspection of the 3rd stage LPT blades, rotate the LPT rotor

until an access window is aligned between a pair of 4th stage

LPT blades, a pair of 4th stage LPT vanes and a pair of 3rd stage

LPT blades.

NOTE: Alignment of the 4th stage LPT blades, a pair of 4th

stage LPT vanes and a pair of 3rd stage blades allow

viewing of and tool insertion to the 3rd stage LPT blade

outer shroud.

Due to the different number of 3rd stage LPT blades

(88) compared to 4th stage LPT vanes and 4th stage

LPT blades (58), there are specific access windows,

located approximately every four (4) or five (5) 4th stage

LPT blades, that are most suitable for insertion of the

tool. Select these windows of opportunity for inspection

of the 3rd stage LPT blades.

b. For inspection of the 4th stage LPT blades, rotate the LPT rotor

until a convenient access window is located.

3. Using the marker, mark the inspection location ID number on the 4th

stage LPT blade located clockwise and adjacent to the access window

to identify the first inspection location, refer to Figure 7.

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C. EQUIPMENT PREPARATION

CAUTION: IT IS IMPORTANT TO USE THE PROPER GAUGE FOR THE

ENGINE MODEL AND STAGE BLADE TO BE INSPECTED,

TABLE I.

TABLE I — NOTCH GAUGE SELECTION

Engine

Model

3rd Stage

LPT Blade

Tool Part

Number

Minimum “T”

End Length

Dimension

Inch (mm)

4th Stage

LPT Blade

Tool Part

Number

Minimum “L”

End Length

Dimension

Inch (mm)

Extension

-209 PWA 104225

(LD 303)

1.035

(26.29)

PWA 104227

(LD 405)

1.665

(42.29)

PWA 104223

(LD 3404 or

LD 3405)

-217 PWA 104225

(LD 303)

1.035

(26.29)

PWA 104227

(LD 405)

1.665

(42.29)

PWA 104223

(LD 3404 or

LD 3405)

-217A PWA 104225

(LD 303)

1.035

(26.29)

PWA 104227

(LD 405)

1.665

(42.29)

PWA 104223

(LD 3404 or

LD 3405)

-217C No

Inspection

Required

Not

Applicable

PWA 104226

(LD 403)

1.755

(44.58)

1.695

(43.05)

PWA 104223

(LD 3404 or

LD 3405)

-219 No

Inspection

Required

Not

Applicable

PWA 104226

(LD 403)

1.755

(44.58)

1.695

(43.05)

PWA 104223

(LD 3404 or

LD 3405)

CAUTION: EACH GAUGE HAS BEEN MARKED WITH THE INSPECTION TOOL PART

NUMBER, ENGINE MODEL, AND BLADE STAGE AND IDENTIFICATION

SHOULD BE CHECKED PRIOR TO INSPECTION.

1. Select the proper notch gauge — PWA 104225 or PWA 104226 or

PWA 104227 — for the engine model and stage blade to be

inspected.

2. Measure the “T” or “L” end using the vernier calipers and ensure the

minimum dimension requirements are met.

CAUTION: IF THE DIMENSION OF THE “T” OR “L” END DOES MEET

THE MINIMUM REQUIREMENT, THE INSPECTION

CANNOT BE PERFORMED.

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3. Assemble the PWA 104224 Mechanical Inspection Tool System.

a. Attach the notch gauge to the PWA 104223 extension tool.

1) Slide the notched end of the gauge into the receptacle of

the extension tool.

2) Rotate the gauge to align the notched end with the bar

within the receptacle end of the extension tool.

3) Continue to slide the gauge until the notched end is over the

bar and the circular groove is aligned with the end of the

receptacle.

4) Tighten the set screw in the receptacle end using the hex

key to secure the gauge in the extension tool.

b. Attach the extension tool to the torque limiting screwdriver.

1) Slide the notched end of the extension tool into the

receptacle of the screwdriver.

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D. INSPECTION PROCEDURE — 3rd Stage LPT Blade (JT8D-209, -217, and

-217A Models)

1. Set the torque limiting screwdriver to 15 inch-pounds, Figure 8.

FIGURE 8

TORQUE LIMITING SCREWDRIVER (LEFT) AND SCALE FOR TORQUE SETTING

(RIGHT)

NOTE: READ THE TORQUE SETTING WITH LINE IN CENTER OF

PLASTIC BUBBLE.

CAUTION: THE TORQUE LIMITING SCREWDRIVER HAS

AN INCH-POUND (INCH LBS) SCALE AND A

NEWTON-METERS (N.M) SCALE ON THE

HANDLE. BE SURE TO USE THE

INCH-POUND SCALE FOR THIS

INSPECTION.

2. Insert the “T” end of the PWA 104225 notch gauge through the access

window in the 4th stage LPT blades and vanes to the outer shroud of

the 3rd stage LPT blades until the circular stop block is against the 4th

stage LPT blade trailing edge, Figure 9.

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FIGURE 9

INSERTION OF THE PWA 104225 3RD STAGE LPT BLADE NOTCH GAUGE FOR THE

3RD STAGE LPT BLADE INSPECTION

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NOTE: The notch gauge is inserted correctly when:

• the “T” end is positioned on the outer shroud of the 3rd stage LPT

blade;

• the circular stop is against the 4th stage LPT blade trailing edge;

• the indicator line on the circular stop block is perpendicular to the

outer shroud; and

• the gauge shaft axis is parallel with the engine center axis.

Tap downward lightly to make sure the “T” end is contacting the outer

shroud of the 3rd stage LPT blade.

3. Attempt to rotate the tool counterclockwise using the torque limiting

screwdriver handle, refer to Figure 9.

NOTE: Rotation of the tool and the indicator line on the circular stop

block 180 degrees indicates that the “T” gauge has spread

apart the pair of 3rd stage LPT blades.

Slipping or ratcheting of the torque limiting screwdriver

handle — as indicated by a clicking sound — and rotation of

the indicator line on the circular stop block less than 180

degrees indicates that the “T” gauge is not spreading apart

the pair of 3rd stage LPT blades.

4. Remove the tool and record the inspection results, Figure 10.

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FIGURE 10

3RD STAGE LPT BLADE INSPECTION RESULTS

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5. Rotate the LPT rotor clockwise (as viewed from the rear of the engine)

approximately four (4) 4th stage LPT blades until the next access

window is reached.

NOTE: The optimum inspection window allows easy insertion of the

tool. It may be necessary to index one or two additional

blades, either in the counterclockwise or clockwise direction,

to achieve the optimum inspection window.

6. Using the marker, mark the inspection location ID number on the 4th

stage LPT blade located clockwise and adjacent to the access window

to identify the inspection location, refer to Figure 7.

7. Repeat steps II.D.2. through II.D.6. until a total of 14 locations are

inspected and rotation back to within four (4) blades of the first

inspection location is achieved.

CAUTION: DO NOT REDUCE THE TORQUE SETTING UNTIL ALL 14

LOCATIONS HAVE BEEN INSPECTED AT 15

INCH-POUNDS.

8. If the tool at the 15 inch-pounds setting spreads the blades apart at

any inspection location, set the torque limiting screwdriver to 10

inch-pounds and repeat steps II.D.2. through II.D.7., starting at the first

inspection location.

NOTE: The inspection at 10 inch-pounds should be conducted at the

same inspection locations as the inspection at 15

inch-pounds.

CAUTION: DO NOT REDUCE THE TORQUE SETTING UNTIL

ALL 14 LOCATIONS HAVE BEEN INSPECTED AT

10 INCH-POUNDS.

9. If the tool at the 10 inch-pounds setting spreads the blades apart at

any inspection location, set the torque limiting screwdriver to 5

inch-pounds and repeat steps II.D.2. through II.D.7., starting at the first

inspection location.

NOTE: The inspection at 5 inch-pounds should be conducted at the

same inspection locations as the inspections at 15

inch-pounds and 10 inch-pounds.

NOTE: If preferred by an operator, it is acceptable to start the

inspection at the lower torque setting of 5 inch-pounds,

increase to 10 inch-pounds and then increase to 15

inch-pounds.

It is strongly recommended, however, that an operator select

one torque setting direction — either 15-10-5 inch-pounds or

5-10-15 inch-pounds — and maintain that direction for all

inspections.

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E. INSPECTION PROCEDURE — 4th Stage LPT Blade (JT8D-209, -217,

-217A, -217C, and -219 Models)

CAUTION: IT IS IMPORTANT TO USE THE PROPER GAUGE FOR THE

ENGINE MODEL/BLADE STAGE TO BE INSPECTED.

REFER TO TABLE I IN SECTION II.C.

1. Set the torque limiting screwdriver to 15 inch-pounds, Figure 11.

FIGURE 11

TORQUE LIMITING SCREWDRIVER (LEFT) AND SCALE FOR TORQUE SETTING

(RIGHT)

CAUTION: THE TORQUE LIMITING SCREWDRIVER HAS AN INCH-POUND (INCH

LBS) AND A NEWTON-METERS (N.M) SCALE ON THE HANDLE. BE

SURE TO USE THE INCH-POUND SCALE FOR THIS INSPECTION.

2. Clean an area in the exhaust duct at the 6 o’clock position slightly

larger than the base of the PWA 107309 notch gauge support. See

Figure 12 Sheet 1.

3. Slide the PWA 107309 Notch Gauge Support Assembly onto the ID of

the turbine exhaust duct at the 6 o’clock position. The base of the

support assembly should be positioned aft of the mixer and forward of

the rivets on the aft end of the duct. It should also be positioned just

left of the 6 o’clock strut on the exhaust case.

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4. Turn the laser guide on the PWA 107309 support fixture to the “ON”

position.

5. Insert the notch gauge tool into the PWA 107309 support fixture.

Insert the “L” end of the proper (PWA 104226 or PWA104227) notch

gauge through the access window in the 4th stage LPT blades until

the circular stop block is against the 4th stage LPT blade trailing edge.

See Figure 12 Sheet 2.

NOTE: At present only the PWA 104226 and PWA 104227 4th stage

LPT Blade Notch Gauges require the use of the PWA

107309 Notch Gauge Support tool during inspection. A

support is not currently available for the 3rd stage blade

inspection. See Figure 12 Sheet 3.

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FIGURE 12 SHEET 1

PWA 107309 NOTCH GAUGE SUPPORT FOR 4TH STAGE LPT BLADE NOTCH

GAUGE

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FIGURE 12 SHEET 2

INSERTION OF THE 4TH STAGE LPT BLADE NOTCH GAUGE FOR THE 4TH STAGE

LPT BLADE INSPECTION

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NOTE: The notch gauge is inserted correctly when:

• the roller of the “L” end is positioned on the outer shroud of the 4th

stage LPT blade;

• the circular stop is against the 4th stage LPT blade trailing edge;

• the indicator line on the circular stop block is perpendicular to the

outer shroud; and

• the gauge shaft axis is parallel with the engine center axis.

Tap downward lightly to make sure the wheel of the “L” end is

contacting the outer shroud of the 4th stage LPT blade.

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FIGURE 12 SHEET 3

4TH STAGE NOTCH GAUGE POSITIONED ON THE PWA 107309 NOTCH GAUGE

SUPPORT FIXTURE

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6. Align the laser guide spot to show on the torque tool stop disk. Align

the laser guide spot so that it is as close to the center of the stop disk

as possible.

7. Attempt to rotate the tool counterclockwise using the torque limiting

screwdriver handle, refer to Figure 12.

NOTE: Rotation of the tool and the indicator line on the circular stop

block 180 degrees indicates that the “L” gauge has spread

apart the pair of 4th stage LPT blades.

Slipping or ratcheting of the torque limiting screwdriver

handle — as indicated by a clicking sound — and rotation of

the indicator line on the circular stop block less than 180

degrees indicates that the “L“ gauge is not spreading apart

the pair of 4th stage LPT blades.

8. Remove the tool and record the inspection results, Figure 13.

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FIGURE 13

4TH STAGE LPT BLADE INSPECTION RESULTS

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9. Rotate the LPT rotor clockwise (as viewed from the rear of the engine)

approximately two (2) 4th stage LPT blades until the next access

window is reached.

NOTE: The optimum inspection window allows easy insertion of the

tool. It may be necessary to index one or two additional

blades, either in the counterclockwise or clockwise direction,

to achieve the optimum inspection window.

10. Using the marker, mark the inspection location ID number on the 4th

stage LPT blade located clockwise and adjacent to the access window

to identify the inspection location, refer to Figure 7.

11. Repeat steps II.E.5. through II.E.11. until a total of 29 locations are

inspected and rotation back to within two (2) blades of the first

inspection location is achieved.

CAUTION: DO NOT REDUCE THE TORQUE SETTING UNTIL ALL 29

LOCATIONS HAVE BEEN INSPECTED AT 15

INCH-POUNDS.

12. If the tool at the 15 inch-pounds setting spreads the blades apart at

any inspection location, set the torque limiting screwdriver to 10

inch-pounds and repeat steps II.E.5. through II.E.12., starting at the

first inspection location.

NOTE: The inspection at 10 inch-pounds should be conducted at the

same inspection locations as the inspection at 15

inch-pounds.

CAUTION: DO NOT REDUCE THE TORQUE SETTING UNTIL

ALL 29 LOCATIONS HAVE BEEN INSPECTED AT

10 INCH-POUNDS.

13. If the tool at the 10 inch-pounds setting spreads the blades apart at

any inspection location, set the torque limiting screwdriver to 5

inch-pounds and repeat steps II.E.5. through II.E.12., starting at the

first inspection location.

NOTE: The inspection at 5 inch-pounds should be conducted at the

same inspection locations as the inspections at 15

inch-pounds and 10 inch-pounds.

NOTE: If preferred by an operator, it is acceptable to start the

inspection at the lower torque setting of 5 inch-pounds,

increase to 10 inch-pounds and then increase to 15

inch-pounds.

It is strongly recommended, however, that an operator select

one torque setting direction — either 15-10-5 inch-pounds or

5-10-15 inch-pounds — and maintain that direction for all

inspections.

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F. EQUIPMENT DISASSEMBLY

1. Switch the laser on the Notch Gauge Support tool to the “OFF”

position.

2. Remove all inspection equipment from the engine.

3. Disassemble the PWA 104224 Mechanical Inspection Tool System.

a. Detach the extension tool from the torque limiting screwdriver.

1) Pull the notched end of the extension tool out of the

receptacle of the screwdriver.

b. Detach the notch gauge — PWA 104225 or PWA 104226 or

PWA 104227 — from the PWA 104223 extension tool.

1) Loosen the set screw in the receptacle end using the hex

key to release the gauge from the extension tool.

2) Slide the notched end of the gauge out of the receptacle of

the extension tool.

4. Store the inspection tooling in the containers provided.

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G. REJECTION CRITERIA

1. Inspection disposition is based on limits provided in the Alert Service

Bulletin A6224.

CAUTION: INSPECTION DISPOSITION AND REJECTION

CRITERIA IS BASED ON INSPECTION RESULTS

FROM 14 INSPECTION LOCATIONS ON THE 3RD

STAGE AND 29 LOCATIONS ON THE 4TH STAGE.

IF MORE LOCATIONS ARE INSPECTED AND THE

SAME INSPECTION CRITERIA IS USED, INSPECTION

DISPOSITION MAY RESULT IN SHORTER

INSPECTION INTERVALS OR EARLIER REMOVAL OF

THE ENGINE.

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H. REPORTING

NOTE: The procedures released for these engine models have been

demonstrated to be effective for other similar engine models. The

correlation data for the torque levels versus shroud cross notch

wear for the 3rd stage LPT blades and JT8D-209, -217 and -217A

4th stage LPT blades is very limited.

Pratt & Whitney requests operator assistance in providing

additional data — torque test results with corresponding shroud

cross notch wear data. This data will provide information that can

be used to revise or confirm the limits selected.

1. Report inspection results to the local Pratt & Whitney Field

Representative.

NOTE: Only inspection results which contain both the torque test

results and corresponding shroud cross notch wear data are

to be reported.

a. Airline, aircraft S/N, engine S/N, engine position, engine total

time and total cycles.

b. Blade stage, blade part number, and total part time and total part

cycles since new and last inspection, if available.

c. Inspection method, and summary of results — location and

torque readings and corresponding shroud cross notch wear

data, Figure 14 and 15.

NOTE: Coordinate with repair shop to obtain corresponding

shroud cross notch wear data for blades measured

during overhaul from the engines rejected by the torque

test using the following procedure.

• Mark all blades prior to rotor disassembly for correlation to the

location of the torque readings.

• Record locations of torque reading on chart, Figure 14 and/or

Figure 15.

• Submit the torque test data with the blades to the blade repair

facility.

• Request the blade repair facility to measure and record the

shroud cross notch wear per the Engine Manual requirements

for all blades in the rotor.

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FIGURE 14, SHEET 1

3RD STAGE LPT BLADE INSPECTION RESULTS

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FIGURE 14, SHEET 2

3RD STAGE LPT BLADE INSPECTION RESULTS

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FIGURE 15, SHEET 1

4TH STAGE LPT BLADE INSPECTION RESULTS

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FIGURE 15, SHEET 2

4TH STAGE LPT BLADE INSPECTION RESULTS

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