# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 2 of 10 Pages Manpower Requirements

1) On

- wing

Time to gain access

0.5 hour (1 person)

Time to inspect Tail Bearing Housing (TBH) Mount Lug Run

- outs

2 hours (2 persons)

Time to restore to serviceable condition

0.5 hour (1 person)

2) In Shop

Time to inspect Tail Bearing Housing (TBH) Mount Lug Run

- outs

2 hours (2 persons)

The Fluorescent Penetrant Inspection (FPI) defined in this Technical Instruction shall only be performed by personnel qualified to FPI Level 2 or higher and in possession of an up to date eyesight record in accordance with EN4179/NAS410 or alternative standards/guidelines accepted by the applicable National Aviati on Authority.

Materials



### OMat 651F

- F2B

- AMS2644 Type 1, Method D, Level 3 (1D3) compliant aerosol penetrant (Fluorescent, Post

- Emulsified, Medium Sensitivity).

OMat 617

– AMS2644 Form d

– Non

- Aqueous Wet Developer

– Aerosol.

Ultra Violet Light Source capable of providing a minimum UV radiation intensity of

1200 μW/cm 2 

### at the inspection surface.

Dark Non

- Reflective cover to darken the area for inspection.

OMat 150

– Acetone.

OMat 2/101

– Lint Free Cloths.

OMat 677

– Penetrant Test Panel.

Visual Aids as per AMM Task 70

- 20

- 02, Fluorescent Penetrant Inspection.

# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 3 of 10 Pages PROCEDURE

– ON WING

WARNING: YOU MUST BE CAREFUL WHEN YOU WORK ON THE ENGINE AFTER THE

ENGINE IS SHUTDOWN. THE ENGINE CAN STAY HOT FOR UPTO ONE

HOUR.

WARNING : YOU MUST NOT TOUCH HOT PARTS WITHOUT APPLICABLE GLOVES. HOT

PARTS CAN CAUSE INJURY. IF YOU GET AN INJURY, TREAT WITH COLD

WATER FOR 10 MINUTES, THEN SEEK MEDICAL AID.

1) To get access to the Tail Bearing Housing (TBH) Mount Lug Run

- outs

i. Open the Fan Cowl Doors in accordance with AMM Task 71

- 13

- 00 , Maintenance Practices to get access

ii. Make the Thrust Reverser unserviceable for maintenance in accordance with

AMM Task 78

- 30

- 00 Deactivation/Activation.

WARNING : YOU MUST MAKE THE THRUST REVE RSER UNSERVICEABL E (INSTALL

AND SAFETY THE INHIBITION DEVICE) BEFORE YOU DO WORK ON OR

AROUND THE THRUST REVERSER. IF YOU DO NOT INSTALL AND SAFETY

THE INHIBITION DEVICE, THERE IS A RISK THAT THE THRUST REVERSER

CAN OPERATE ACCIDENTALLY. THIS CAN CAUSE INJ URY TO PERSON

AND/OR DAMAGE TO THE EQUIPMENT.

iii. Open the Fan Exhaust Cowls in accordance with the AMM, Task 78

- 26

- 00

iv. Use appropriate staging to gain access to the Tail Bearing Housing TBH

2) Carry out the inspection on the Mount Lug Run

- outs

WARNING : PROTECTIVE GLOVES AND SAFETY GLASSES MUST BE WORN AT ALL

TIMES DURING THE INSPECTION . IF YOU GET AN INJURY, SEEK MEDICAL

AID IMMEDIATELY

.

i. This inspection must be performed in accordance with the requirements of AMM

70

- 20

- 02, Fluorescent Penetrant Inspection.

ii. Local cleaning of the inspection areas must be completed prior to FPI.



### iii. Apply OMat 150

– Acetone to a clean OMat 2/101

– Lint Free Cloth.

iv. Clean the inspection surfaces (see Figures 1 and 2) with the moistened

cloth.

v. Ensure that all contaminants have been removed. If necessary repeat steps (iii) and (iv) in order to achieve this.

NOTE: THE INSPECTION SURFACE, MUST BE CLEAN, DRY AND FREE FROM SOILS, OIL, GREASE, PAINT, COATINGS, CORROSION PRODUCTS, SCALE, SMEARED

METAL , WELDING FLUX, CHEMICAL RESIDUES OR ANY OTHER MATERIAL THAT COULD PREVENT PENETRANT FROM ENTERING A DISCONTINUITY,

AFFECT PROCESS PERFORMANCE OR PRODUCE AN UNACCEPTABLE

BACKGROUND.



### vi. Allow 10 minutes for the area to completely dry prior to penetrant applic ation.

# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 4 of 10 Pages vii. 

### Penetrant Application

- Apply OMat 65 1F

– 1D3 Penetrant to the inspection areas (Figure s 1 and 2 ) by brush or sponge applicator. The penetrant must be dispensed from a sealed aerosol can and any unused penetrant must go to

waste.

viii. Ensure that the i nspection area is fully covered with penetrant with the aid of a UV lamp.

ix. Apply OMat 651F

– 1D3 Penetrant to the OMat 677

– Penetrant Test Panel.

x. Leave the penetrant in contact with the components for 30 minutes.

NOTE: THE PENETRANT CONTACT TIME MUST NOT EXCEED 1 HOUR. IF IT DOES THE

PENETRANT MUST BE REAPPLIED AND 5 MINUTES CONTACT TIME

ALLOWED.

xi. Penetrant Removal

- After the 30 minutes contact time, remove the excess penetrant from the inspection surface and the OMat 677

– Penetrant Test Panel by wip ing thoroughly with a clean OMat 2/101

– Lint Free Cloth.

xii. Whilst illuminating with UV light, wipe off the penetrant with a clean

OMat 2/10

- Lint Free Cloth moistened with OMat 150

– Acetone. Use the minimum application necessary to achieve acceptable bac kground fluorescence and ensure than acetone is not allowed to flow on the inspection surface

.

xiii. Ensure that all traces of the OMat 150

– Acetone have been completely

removed.

xiv. Develop

- Apply a light, even coating of OMat 617

– Non

- Aqueous Wet Developer fr om a sealed aerosol can to the inspection area and the OMat 677

– Penetrant Test Panel.

xv. Allow 10 minutes contact time for the developer.

xvi. Cover the region of the engine with a dark non

- reflective cover in order to reduce the white light levels.

xvii. Ensure th ere are no white light sources or fluorescent items (including clothing) within the inspection area or the inspector’s field of vision.

xviii. Do not wear darkened or light sensitive glasses.

xix. Allow 1 minute for eye adaptation to the darkened area.

xx. Illuminate t he OMat 677

– Penetrant Test Panel with UV light at an intensity of no

less than 1200 μW/cm 2 in the darkened area.

xxi. Inspect the OMat 677

– Penetrant Test Panel and check that the 4 largest indications are visible and match the control photograph for that i ndividual panel.

xxii. Illuminate the inspection surface with UV light at an intensity of no less than

1200 μW/cm 2 in the darkened area.

xxiii. Inspect the Mount Lug Run

- Outs for crack indications.

# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 5 of 10 Pages xxiv. The “Wipe Off” technique can be used to aid the evaluation of any indications and must be performed as directed by AMM 

### 70

- 20

- 02

, Fluorescent Penetrant Inspection.

xxv. The cause of all indications must be evaluated under white light using visual aids, such as magnification, as appropriate.

xxvi. Record any suspected crack indication in Appendix x. Report any suspected

crack indications to Rolls

- Royce local representative

.

xxvii. Post Clean

- Once all indications have been evaluated and recorded, remove the
penetra nt processing materials from the inspection surface by wiping with a clean

OMat 2/101

– Lint Free Cloth moistened with OMat 150

– Acetone

.

3) Close access to the Tail Bearing Housing ( TBH )



### i. Ma 

### ke sure the work area is clean and clear of tools and other items.

ii. Close the Fan Exhaust C owls in accordance with AMM 78

- 26

- 00,

Maintenance Practices

.

iii. Make the Thrust R everser serviceable after maintenance in accordance

with AMM 78

- 30

- 00, Deactivation/Activation as necessary.

iv. Close the Fan Cowl Doors in accordance with AMM Task 71

- 13

- 00,

Maintenance Practices.

# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 6 of 10 Pages PROCEDURE

– IN SHOP

1) Carry out the inspection on the Mount Lug Run

- outs

WARNING : PROTECTIVE GLOVES AND SAFETY GLASSES MUST BE WORN AT ALL

TIMES DURING THE INSPECTION . IF YOU GET AN INJURY, SEEK MEDICAL

AID IMMEDIATELY

.

i. This inspection must be performed in accordance with the requirements of

70

- 00

- 00

, Overhaul Process 210, Fluorescent Penetrant Inspection.

ii. Local cleaning of the inspection areas must be completed prior to FPI.



### iii. Apply OMat 150

– Acetone to a clean OMat 2/101

– Lint Free Cloth.

iv. Clean the inspection surfaces (see Figures 1 and 2) with the moistened

cloth.

v. Ensure that all contaminants have been removed. If necessary repeat steps (iii) and (iv) in order to achieve this.

NOTE: THE INSPECTION SURFACE, MUST BE CLEAN, DRY AND FREE FROM SOILS, OIL, GREASE, PAINT, COATINGS, CORROSION PRODUCTS, SCALE, SMEARED METAL, WELDING FLUX, CHEMICAL RESIDUES OR ANY OTHER MATERIAL THAT COULD PREVENT PENETRANT FROM ENTERING A DISCONTINUITY,

AFFEC T PROCESS PERFORMANCE OR PRODUCE AN UNACCEPTABLE

BACKGROUND.



### vi. Allow 10 minutes for the area to completely dry prior to penetrant application.

vii. 

### Penetrant Application

- Apply OMat 65 1F

– 1D3 Penetrant to the inspection areas (Figure s 1 and 2 ) by brush or spo nge applicator. The penetrant must be dispensed from a sealed aerosol can and any unused penetrant must go to

waste.

viii. Ensure that the inspection area is fully covered with penetrant with the aid of a UV lamp.

ix. Apply OMat 651F

– 1D3 Penetrant to the OMat 677

– Penetrant Test Panel.

x. Leave the penetrant in contact with the components for 30 minutes.

NOTE: THE PENETRANT CONTACT TIME MUST NOT EXCEED 1 HOUR. IF IT DOES THE

PENETRANT MUST BE REAPPLIED AND 5 MINUTES CONTACT TIME

ALLOWED.

xi. Penetrant Removal

- After the 30 minutes contact time, remove the excess penetrant from the inspection surface and the OMat 677

– Penetrant Test Panel by wiping thoroughly with a clean OMat 2/101

– Lint Free Cloth.

xii. Whilst illuminating with UV light, wipe off the penetrant with a clean

OMat 2/10

- Lint Free Cloth moistened with OMat 150

– Acetone. Use the minimum application necessary to achieve acceptable background fluorescence and ensure than acetone is not allowed to flow on the inspection surface

.

# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 7 of 10 Pages xiii. En sure that all traces of the OMat 150

– Acetone have been completely

removed.

xiv. Develop

- Apply a light, even coating of OMat 617

– Non

- Aqueous Wet Developer from a sealed aerosol can to the inspection area and the OMat 677

– Penetrant Test Panel.

xv. Allow 10 minutes contact time for the developer.

xvi. Cover the region of the engine with a dark non

- reflective cover in order to reduce the white light levels.

xvii. Ensure there are no white light sources or fluorescent items (including clothing) within the inspection are a or the inspector’s field of vision.

xviii. Do not wear darkened or light sensitive glasses.

xix. Allow 1 minute for eye adaptation to the darkened area.

xx. Illuminate the OMat 677

– Penetrant Test Panel with UV light at an intensity of no

less than 1200 μW/cm 2 in the darkened area.

xxi. Inspect the OMat 677

– Penetrant Test Panel and check that the 4 largest indications are visible and match the control photograph for that individual panel.

xxii. Illuminate the inspection surface with UV light at an intensity of no less than

1200 μW/cm 2 in the darkened area.

xxiii. Inspect the Mount Lug Run

- Outs for crack indications.

xxiv. The “Wipe Off” technique can be used to aid the evaluation of any indications and must be performed as directed by 70

- 00

- 00

, Overhaul Process 210,

Fluorescent P enetrant Inspection.

xxv. The cause of all indications must be evaluated under white light using visual aids, such as magnification, as appropriate.

xxvi. Record any suspected crack indication in Appendix 3 . Report any suspected

crack indications to Rolls

- Royce loc al representative

.

xxvii. Post Clean

- Once all indications have been evaluated and recorded, remove the penetrant processing materials from the inspection surface by wiping with a clean

OMat 2/101

– Lint Free Cloth moistened with OMat 150

– Acetone

.

# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 8 of 10 Pages Figure 1

- Mount Lug Run Outs

Figure 2

- Inspection Areas Inspection Areas:

The curved faces in these 2 positions on

each side of the engine must be inspected . In addition,

a pproximately

5 mm coverage is required around the

corners. 250 mm

# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 9 of 10 Pages APPENDIX 1

Trent 900 Engines to be inspected ON WING using this procedure

Engine Number

91035

9103 9

91048

APPENDIX 2

Trent 900 Engines to be inspected I N SHOP using this procedure

Engine Number

91047

# Technical Variance

Continuation Sheet TV No.

124801

Issue 2

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 10 of 10 Pages APPENDIX 3

This form to be completed for every engine/component inspected

Results to be sent to Rolls

- Royce via your Service Representative



## Feedback Sheet TV124801

Overhaul Base (if applicable)

Operator
Engine Mark

Date of Inspection
Engine Serial Number
Engine Hours Since New
Engine Cycles Since New
Component Part Number
Component Serial Number
Component Hours Since New
Component Cycles Since New

Inspection result and comments On Wing Inspection of Mount Lug Run

outs (if applicable) In Shop Inspection of Mount Lug Run

- outs (if applicable)