# Repeater Technical Variance

© Rolls

- Royce plc (date as shown below).

The information in this document is the property of Rolls

- Royce plc and may not be copied, communicated to a third party, or

used for any purpose other than that which it is supplied without the express written consent of Rolls

- Royce plc.

This is a repeat application technical variance. It is the responsibility of the operator / overhaul base to control the application

of this document.

This document is supplemental to the Manual(s) specified below and should be suitably stored in accordance with local

airworthiness requirements.

Declaration of Approval

This document is approved under the authority of Airbus EASA Design Organisation Approval no. EASA.21J.031.

Refer to Repair Design Approval Sheet reference no

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 1 of Pages 17 Technical Variance No. 132217 Issue 5 Date 23 MAY 2013

Operator / Applicant ALL OPERATORS /

ALL APPLICANTS Original Request No. DK_08_03_2013

Engine Type RB211 Engine Mark(s) TRENT 900 ALL ENGINE MARKS

Part Description LP TURBINE EXHAUST CASE (TAIL BEARING HOUSING)

Part No. FW35923, FW51434 , FW27718

Manual Title AMM Ref. NA ATA Ref. 72

- 5 2

- 51

TV Title MOUNT LUG FORGING LEADING EDGE INSPECTIONS

Hours NA Cycles NA

Existing Requirement

The Aircraft Maintenance Manual (AMM) do es not contain a procedure to inspect the Tail Bearing Housing

(TBH) Mount Lug Forging Leading Edge (LE) area for crack indications on wing

Requested Variance

Currently there is a requirement to inspect the TBH Mount Lug Forging LE ar ea on Trent 900 engines on

wing

.

NMSB72

- AH154 will follow the issue of this repeater TV and will include details of the new inspection. This

repeater TV includes the details of the inspection until NMS B72

- AH154 is finalised and issued. This

Technical Variance may be applied until 28 th June 2013

.

The results of this inspection are to be reported to Rolls

- Royce.

Summary of Investigation and Conclusions

Rolls

- Royce Engineering has reviewed the above req uirement and an inspection technique has been developed. This TV is issued to

instruct the inspection of the TBH Mount Lug Forging LE area.

Issue 2 of this Repeater Technical Variance is released to update the fly on and re inspection requirements for c rack

indications in the Mount Lug Forging LE area. Additionally, inspection and acceptance criteria for fail safe catcher damage a re

updated for clarity.

Issue 3 is released to correct a formatting error

.

Issue 4 is released to correct an error in task reference for removal and installation of the aft exhaust plug

.

Issue 5 is released to make the removal and installation of the exhaust n ozzle and forward and aft exhaust plugs , optional

tasks

.

Approval on Behalf of Rolls

- Royce

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 2 of Pages 17 A. Manpower Requirements

1) On

- wing

(a) Time to gain access

2.5 hours (2 persons)

(b) Time to inspect Mount Lug Forging LE Areas

2 hours (2 persons)

(c) Time to restore to serviceable condition

2.5 hours (2 persons)

The FPI defined in this Technical Instruction shall only be performed by personnel qualified to Fluorescent

Penetrant Inspection FPI Level 2 or higher and in possession of an up to date eyesight record in

accordance with EN4179/NA S410 or alternative standards/guidelines accepted by the applicable National

Aviation Authority.

B. Material Price and Availability

OMat 632

– Aerosol penetrant

- Commercially Available

OMat 617

– Aerosol developer

- Commercially Available

OMat 150

– Acetone

- Commercially Available

OMat 2/101

– Lint Free Cloths

- Commercially Available

OMat 677

– Penetrant Test Panel

- Commercially Available

C. Tooling Price and Availability

Dark Non

- Reflective cover to darken the area for inspection

– Commerciall y Available

UV Light source

– Commercially Available

Mirror

– Commercially Available

D. References

(1) Aircraft Maintenance Manual (AMM):

(a) 71

- 13

- 00, Maintenance Practices, Opening of Fan Cowl Doors

(b) 78

- 26

- 00, Maintenance Practices, Opening/Closing of the Fan Exhaust

Cowl or Thrust Reverser

(c) 78

- 30

- 00, Deactivation/Reactivation, Make the Thrust Reverser

Unserviceable for Maintenance

(d) 78

- 11

- 41

- 000

- 801

- A Removal of the Exhaust Nozzle

(e) 78

- 11

- 42

- 000

- 804

- A Removal of the Aft Exhaust Plug

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 3 of Pages 17 (f) 78

- 11

- 42

- 000

- 803

- A Removal of the Forward Exhaust Plug

(g) 78

- 11

- 41

- 400

- 801

- A Installation of the Exhaust Nozzle

(h) 78

- 11

- 42

- 400

- 804

- A Installation of the Aft Exhaust Plug

(i) 78

- 11

- 42

- 400

- 803

- A Installation of the Forward Exhaust Plug

E. On

- Wing

– Mount Lug Forging LE Area Inspection

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 mount lug forging LE Area

(i) Open the Fan Cowl Doors in acc ordance 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 REVERSER UNSERVICEABLE (IN STALL

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 INJURY TO PERSON

AND/OR D AMAGE TO THE EQUIPMENT.

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

- 26

- 00

(iv) Remove the Exhaust Nozzle to allow access to the rear of the TBH in

accordance with AMM, Task 78

- 11

- 41

- 000

- 801

- A

(v) Remove the Aft Exhaust P lug in accordance with AMM, Task 78

- 11

- 4 2

- 000

- 804

-

A

(vi) Remove the Forward Exhaust Plug in accordance with AMM, Task 78

- 11

- 42

-

000

- 803

- A

NOTE: STEP S ( iv ) TO ( vi ) ARE OPTIONAL TASKS INTENDED TO IMPROVE ACCESS

TO THE TBH. IF SUITABLE ACCESS CAN BE GAINED WITHOUT

PERFOR MING SOME OR ALL OF TASKS ( iv ) TO ( vi ) THEN THEY ARE NOT

REQUIRED.

(vii) Use appropriate staging and platforms to gain access to the Tail Bearing Housing

2) Processing the pene trant test panel

(i) The OMat 677

– penetrant test panel must be processed at the beginning of

each shift and viewed in each engine that is to be inspected during the shift in

order to ensure that the test environment and materials are acceptable.

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 4 of Pages 17 (ii) Ensure the OMat 677

– penetrant test panel is clean and there is no residual

fluorescence.

(iii) Cover the region of the engine to be inspected with a dark non

- reflective cover in

order to reduce the white light levels in the leading edge inspectio n area.

(iv) Apply OMat 632 penetrant to the OMat 677

– penetrant test panel by sponge

applicator or brush. The penetrant must be dispensed from a sealed aerosol can

and any unused penetrant must go to waste following the inspection.

(v) Leave the pen etrant in contact with the panel for 20 minutes.

(vi) After the 20 minutes contact time, take the OMat 677 penetrant test panel inside

the darkened area to process. Allow 3 minutes for eye adaptation to the low light

levels.

(vii) Remove the exces s penetrant from the panel surface by wiping thoroughly with a

clean, dry OMat 2/101

– lint free cloth whilst illuminating the panel with UV light.

(viii) Soak a clean OMat 2/10

- lint free cloth in water and then gently squeeze the

excess water out to reduce the flow of water on the panel surface.

(ix) Whilst illuminating the OMat 677

– penetrant test panel with UV light, wipe off the

penetrant with the wet cloth before immediately wiping over with a clean, dry

OMat2/10 lint free cloth. Repeat this process using the minimum application

necessary to achieve acceptable background fluorescence.

(x) Ensure that the panel is dry by wiping with a clean, dry OMat2/10 lint free cloth.

(xi) Apply a light, even coating of OMat 617

– non

- aqueous wet devel oper from a

sealed aerosol can to the OMat 677

– penetrant test panel.

(xii) Allow 10 minutes contact time for the developer prior to inspecting the panel.

(xiii) Ensure there are no white light sources or fluorescent items (including clothing)

withi n the darkened area.

(xiv) Hold the OMat 677

– penetrant test panel alongside the leading edge of the Top

Core Vanes and illuminate it with UV light.

(xv) Inspect the OMat 677

– penetrant test panel and check that the visible

indications match the control photograph for that panel.

(xvi) If the panel matches the photograph then the inspection materials and

environment are acceptable and the inspections can be performed.

(xv ii) Repeat steps (xiii) to (xvi) for each engine to be inspected during the shift.

Ensure that the inspection area is darkened for each engine.

(xviii) Restore the OMat 677

– penetrant test panel to a completely clean condition and

ensure there is no residual fluorescence and store in acetone

.

3 ) Carry out the inspection of the Mount Lug Forging LE Area

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

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

AID IMME DIATELY.

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 5 of Pages 17 (i) Clean the inspection areas (See Fig. 2 ) with a clean OMat 2/101

– lint free cloth

moistened with OMat 150

– acetone.

(ii) Discard the soiled cloth after use.

(iii) Repeat the swabbing using fresh OMat 150

– acetone and a fresh OMat 2 /101

– lint free cloth until all deposits have been removed.

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

MATE RIAL THAT COULD PREVENT PENETRANT FROM ENTERING A

DISCONTINUITY, AFFECT PROCESS PERFORMANCE OR PRODUCE AN

UNACCEPTABLE BACKGROUND.

(iv) Allow 5 minutes for the area to completely dry prior to penetrant application.

(v) Apply OMat 632 penetrant to the inspection areas in Fig.2. The penetrants must

be dispensed from a sealed aerosol can and any unused penetrant must go to

waste.

(vi) Ensure that the inspection areas are fully covered with penetrant with the aid of

the UV lamp and mirror.

(vii) Leave the penetrant in contact with the components for 20 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.

(viii ) After the 20 minutes contact time, remove the excess penetrant from the

inspection surface by wiping thoroughly with a clean OMat 2/101

– lint free cloth.

( i x) Soak a clean OMat 2/10

- lint free cloth in water and then gently squeeze the

excess water o ut to reduce the flow of water on the component surface.

(x) Whilst illuminating the inspection area with UV light, wipe off the penetrant with

the wet cloth before immediately wiping over with a clean, dry OMat2/10 lint free

cloth. Repeat this process using the minimum application necessary to achieve

acceptable background fluorescence.

(xi) Ensure that the inspection area is dry by wiping with a dry OMat2/10 lint free

cloth.

(xii) Apply a light, even coating of OMat 617

– non

- aqueous wet devel oper from a

sealed aerosol can to the inspection area

.

(xi ii ) Allow a minimum of 10 minutes and a maximum of 15 minutes contact time for

the developer prior to inspection.

(x i v) Cover the region of the engine with a dark non

- reflective cover in ord er to reduce

the white light levels.

(xv) Ensure there are no white light sources or fluorescent items (including clothing)

within the inspection area.

(xvi) Positioned inside the darkened area, allow 3 minutes for eye adaptation to the

low light levels.

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 6 of Pages 17 (x vii ) Illuminate the inspection surfaces with UV light in the darkened area and view by

line of sight or by using the mirror as necessary.

(x viii ) Assess the Inspection areas for crack indications. White light may be used to aid

assessment

(xix ) The “Wipe Off” technique shall be used to determine the nature of any

indications.

1. Dampen a cotton swab with acetone.

2. Wipe once across the indication.

3. Allow the acetone to evaporate and inspect immediatel y.

4. If the indication reappears then record it as a crack. If the indication does

not reappear then apply a light, even coating of OMat 617

– non

aqueous wet developer from a sealed aerosol can to the area.

5. Allow the solvent in the developer to evap orate and inspect immediately.

6. If the indication reappears record it as a crack. If the indication does not

reappear then allow 10 minutes contact time for the developer

.

7. If the indication reappears after the 10 minutes contact time then record

it as a crack. If the indication does not reappear then that area is

acceptable

.

(xx) Record any suspected crack indication in Appendix 1

.

Determine whether the indication is cont inuous or discontinuous where possible

.

Measure the length of the indication using a fluorescent comparator gauge.

Photograph any crack indications.

(xxi) No cracks detected ACCEPT

Any discontinuous cracks that total less than 6mm RE

- INSPECT

in length (see Fig.3) WITHIN 75 FC

Any discontinuous cracks that total greater than or RE

- INSPECT

equal to 6mm and less than 9mm in length (see Fig.3) WITHIN 50 FC

Any discontinuous cracks that total greater than or REMOVE ENGINE

equal to 9 mm and less than 12mm in length (see Fig.3) WITHIN 100 FC

Any discontinuous cracks that total 12 mm in length REMOVE ENGINE

or greater (see Fig.3)

Any single continuous crack less than 2mm in length RE

- INSPECT

(see Fig. 4 ) WITHIN 75 FC

Any single continuous crack greater than or equal RE

- INSPECT

to 2mm and less than 5mm in length (see Fig. 4 ) WITHIN 50 FC

Any single continuous crack greater than or equal REMOVE ENGINE

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 7 of Pages 17 to 5mm and less than 8mm in length (see Fig. 4 ) WITHIN 100 FC

Any single continuous crack equal to or greater than REMOVE ENGINE

8mm in length (see Fig. 4 )

(xx ii) 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.

4 ) Inspect the fail safe catcher for sign s of contact

(i) Visually inspect the LE face of the fail safe catcher (see Fig. 5 )

NOTE: ON WING VISIBILITY OF THE LE FACE OF THE FAIL SAFE CATCHER IS

LIMITED. VIEW AS MUCH OF THE LE FACE AS ACCESS ALLOWS AND

ASSESS FOR DAMAGE SIMILAR TO THAT IN FIG

. 6

.

NOTE: IF DAMAGE IS FOUND ON FAIL SAFE CATCHER USE BSI EQUIPMENT TO

MEASURE THE EXTENT OF THE DAMAGE IF REQUIRED.

(ii) If Scored, galled, fretted or dented on the centre lug (fail safe lug) front surface:

(1) Not more than 8,00 mm in width and 1,00 mm in depth ACCEPT

(2) More than 2,60 mm in depth REJECT

(3 ) More than in (1) and less than in (2) REPAIR

, FRS3253 AMM

TASK 70

- 42

-

11

- 300

- 801

- A

within 100

Flight Cycles

(4 ) If the minimum cross sectional area (Area A , see Fig. 7) REJECT

of the catcher in the repaired areas is less than 1155 sqmm

after repair

.

(i ii ) Photograph any damage and note location of the damage on the fail safe catcher

and or the engine mounts. See Fig. 6 for example photographs of typical damage. Any Damage REJECT

5 ) Measure the distance s between the fail safe catcher and the engine mount

(i) When the engine is fully cooled, measure the distance s A and B as illustrated in

Fig. 8

.

(ii) Record in Appendix 1

.

6 ) Close access to the TBH

(i) Make sure the work area is clean and clear of tools and other items.

(i i ) If applicable, i nstall the Forward Exhaust Plug in accordance wi th AMM, Task 78

-

11

- 42

- 400

- 803

- A.

(iii ) If applicable, i nstall the Aft Exhaust Plug in ac cordance with AMM, Task 78

- 11

-

4 2

- 400

- 804

- A

.

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 8 of Pages 17 ( i v ) If applicable, i nstall the Exhaust Nozzle in accordance with AMM, Task 78

- 11

- 41

-

400

- 801

- A

.

(v ) Close the Fan Exhaust Cowls in accordance with AMM 78

- 26

- 00, Maintenance

Practices.

(vi) Make the Thrust Reverser serviceabl e after maintenance in accordance with

AMM 78

- 30

- 00, Deactivation/Activation as necessary.

(vii ) Close the Fan Cowl Doors in accordance with AMM Task 71

- 13

- 00, Maintenance

Practices.

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 9 of Pages 17

Figure 1

– Tail Bearing Housing

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 10 of Pages 17 Figure 2

- Mount Lug Forging LE Area

VIEW LOOKING AFT

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 11 of Pages 17 Figure 3

– Discontinuous crack indication

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 12 of Pages 17 Figure 4

- Continuous crack indication

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 1 3 of Pages 17 Figure 5

- Fail Safe Catcher Inspection locations FWD

FWD View looking

FWD

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 14 of Pages 17 Figure 6

- On Wing

- Fail Safe Catcher Damage

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 15 of Pages 17 Figure 7

- Repair Acceptance Criteria

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 16 of Pages 17 Figure 8

– Distances between fail safe catcher and engine mount FWD

A B

# Technical Variance

Continu ation Sheet TV No. 132217

Issue 5

Rolls

- Royce plc. Proprietary Information

– Not for Manufacture

Page 17 of Pages 17

APPENDIX 1

This form (or similar) to be completed for every engine/component inspected

Results to be sent to Rolls

- Royce via your Service Representative



## Feedback Sheet TV 132 217

Aircraft and Engine Position

Operator

Date of Inspection

Engine Serial Number

Engine Hours Since New

Engine Cycles Since New

08 Module Serial Number

08 Module Hours Since New

08 Module 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 Forging

Le ading Edge Area Any crack indications?

Max continuous length

Max discontinuous length

Photographs of crack

indications



### On Wing i n spection of

Fail Safe Catcher LE

face and any

photographs of damage

Distance A between Fail

Safe Catcher LE and

Engine mount (mm)

Distance B between Fail

Safe Catcher TE and

Engine mount (mm)