# Rolls-Royce Non-Modification Service Bulletin 72-AK188: Revision 2

- Rights: © Rolls-Royce plc. Filed by the FAA in regulations.gov docket FAA-2022-1244, the docket of AD 2023-04-14. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Rolls-Royce Non-Modification Service Bulletin 72-AK188](https://openairdocs.org/service-documents/rolls-royce/72-ak188.md)
- Title as filed: Rolls-Royce NMSB TRENT XWB 72-AK188 Rev 2
- Pages: 44
- PDF: https://openairdocs.org/files/sha256/c0/33/c033fe462f2c72f5e9efd5df5f945647c8365755935126f6e02bfc2964395a2f
- Page: https://openairdocs.org/service-documents/rolls-royce/72-ak188/file/c033fe462f2c

## Text

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### Page 1

This document transmits Revision 2 to Service Bulletin TRENTXWB-72-AK188
Document History
Service Bulletin Revision Status Supplement Revision Status
Initial Issue Aug.13/19
Revision 1 Sep.20/19
Bulletin Revision 2
Remove Incorporate Reason for change
Pages 1 to 37 of the
Service Bulletin
Pages 1 to 38 of the
Service Bulletin
Updated to clarity to
limits in 3. Accomplishment
Instructions and to update
Appendix 1.
Page 1 of Appendix 1 Page 1 and 2 of
Appendix 1
Updated to clarity to
limits in 3. Accomplishment
Instructions and to update
Appendix 1.
All pages of
Appendix 2
Page 1 of Appendix 2 Updated to clarity to
limits in 3. Accomplishment
Instructions and to update
Appendix 1.
Printed in Great Britain
Dec.17/19
TRENT XWB SERIES PROPULSION SYSTEMS NON-MODIFICATION SERVICE BULLETIN
ALERT TRENT XWB 72−AK188
Transmittal - Page 1 of 3
Date
ALERT
CHECK THAT ALL PREVIOUS TRANSMITTALS HAVE BEEN INCORPORATED 
If any have not been received please advise Customer Data Services, Rolls-Royce plc, Derby, England 
©Rolls-Royce plc (date as above) Printed in Great Britain

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LIST OF EFFECTIVE PAGES
The effective pages to this Service Bulletin following incorporation of Revision
2 are as follows:
Page Revision Number Revision Date
Bulletin
R     1 2 Dec.17/19
R     2 2 Dec.17/19
R     3 2 Dec.17/19
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Appendix 1
R     1 2 Dec.17/19
R     2 2 Dec.17/19
Appendix 2
Printed in Great Britain
TRENT XWB 72−AK188
Transmittal - Page 2

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R     1 2 Dec.17/19
Printed in Great Britain
TRENT XWB 72−AK188
Transmittal - Page 3

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1. Planning Information
A. Effectivity
Airbus A350-900
All Trent XWB-75 Engines
All Trent XWB-79 Engines
All Trent XWB-79B Engines
All Trent XWB-84 Engines
B. Reason
(1) Problem
The purpose of the engine mount is to position the engine relative to the
aircraft pylon and to transfer all loads and rotational moments between
engine and aircraft pylon.
The front Engine Mount Support Structure (EMSS) comprises of the LP
Compressor Outlet Guide Vane (OGV) assembly and OGV Outer Mount Ring
Assembly (CSN 72354601150).
Revised analysis of these parts when the Front Mount Catcher Lug is
engaged in the failsafe condition has now been undertaken using more
advanced modelling techniques. This gives a more comprehensive
understanding of the loading and therefore stresses in the structure. This
analysis predicts that once the Front Engine Mount is in the failsafe
condition, the most highly stressed LP Compressor OGV (CSN 72354601500)
has a life that could be substantially lower than one shop visit.
This Non-Modification Service Bulletin (NMSB) introduces an inspection to
protect against the front engine mount entering the failsafe condition via
a failure of the OGV Outer Mount Ring Assembly outer rail lug fillet.
(2) Safety Intent
The safety intent of this Non-Modification Service Bulletin (NMSB) is to
confirm that the OGV Outer Mount Ring Assembly lug fillet area is not
cracked, to prevent any potential progression to failsafe operation when
the life of the EMSS is predicted to be low and failure of the EMSS could
occur.
ENGINE - RING, ASSY OGV OUTER MOUNT - FLUORESCENT PENETRANT INSPECTION OF THE MOUNT
RING OUTER RAIL LUG FILLETS - NON-MODIFICATION SERVICE BULLETIN - MOD.72-AK188
Printed in Great Britain
TRENT XWB 72−AK188
Page 1 of 38
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C. Description
This NMSB instructs the repeat inspection of the OGV Outer Mount Ring Assembly
using a fluorescent penetrant technique (FPI).
Accomplishment of this NMSB is to be recorded in accordance with local Service
Bulletin tracking system procedures and a completed copy of Appendix 1 (or
similar form) returned to your Rolls-Royce Representative upon completion of
the inspection.
Revision 1 of this NMSB was issued to correct a cleaning procedure reference in
3.B In-Shop Accomplishment Instructions.
R
R
Revision 2 of this NMSB is issued to clarify the limits for redeposited
material/blackspots in 3.A. and 3.B. Accomplishment Instructions and to clarify
labelling of the fillets in Appendix 1.
R
R
R
D. Compliance
(1) On-Wing
ALERT
This Non-Modification Service Bulletin is anticipated to be the subject of
an EASA Airworthiness Directive.
Carry out 3. A. Accomplishment Instructions on engines listed in 1. A.
Effectivity before achieving 2000 flight cycles since new and every 1000
flight cycles thereafter. For engines which have exceeded 1700 flight
cycles since new at the point of publication of this NMSB and not embodied
this NMSB, inspect within 300 flight cycles after the publication of the
NMSB or before 30th April 2020 whichever occurs first and thereafter at
intervals of no more than 1000 flight cycles.
For engines ESN 21021, ESN 21032, ESN 21033, ESN 21038, ESN 21041, ESN
21043, ESN 21044, ESN 21065, ESN 21088 and ESN 21188 carry out 3.A.
Accomplishment Instructions before 30th November 2019 and thereafter at
intervals of no more than 1000 flight cycles.
(2) In-Shop
ALERT
Carry out the inspection in accordance with 3.B. Accomplishment
Instructions on engines listed in 1.A. Effectivity at any module shop
visit Workscope of Level 1 (Serviceability) or above if the engine is at
1750 flight cycles since new or greater and the inspection has not been
carried out in the last 250 flight cycles.
Printed in Great Britain
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Any applicable repeat inspection requirements for mount rail lug fillets
as defined in this NMSB must be recorded in the carry forward sheet. If an
inspection is completed In-Shop, it is the responsibility of the MRO
facility to report the inspection results in accordance with the
instructions using the feedback form (or similar) in the NMSB.
E. Approval
The technical content of this Non-Modification Service Bulletin was approved
under the authority of Design Organisation Approval EASA.21J.065 on Aug.12/19
and was re-approved Dec.17/19.
R
R
F. Manpower
(1) On-wing
(a) Time to gain access
0.5 hours (1 person * 0.5 hours) - Estimated
(b) Time to inspect
2 hours (1 person * 2 hours) - Estimated
The Fluorescent Penetrant Inspection (FPI) defined in this NMSB shall
only be performed by personnel qualified to FPI Level 2 or higher and
in possession of up-to-date eyesight record in accordance with
EN4179/NAS410 or alternative standards/guidelines accepted by the
applicable National Aviation Authority.
(c) Time to restore to serviceable condition
0.5 hours (1 person * 0.5 hours) - Estimated
(2) In-shop
Not Applicable
NOTE: The parts affected by this NMSB are accessible in-shop when carrying
out a Level 1 or above workscope.
G. Material Price and Availability
For Material price and availability contact your assigned Rolls-Royce
Representative.
Printed in Great Britain
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H. Tooling Price and Availability
Part Description Quantity
Fan case access ladders RRT081482 (or equivalent) 1
Dark Non-Reflective cover
to darken the area for
inspection
No specific As necessary
Battery powered
Ultraviolet Light Source
capable of providing a
minimum UV radiation
intensity of 1200
microwatts per square
centimetre at the
inspection surface.
No specific 1
Battery powered White
light source, capable of
providing a minimum of
1000 Lux at the inspection
surface
No specific 1
Temporary stand/tripod for
positioning inspection
lights
No specific 1
Calibrated light
radiometer, containing
both UV and visible sensor
No specific 1
I. References
(1) Maintenance Procedures:
(a) A350-A-71-13-XX-00001-398A-A: Opening of the Fan Cowl Doors with the
Power Door Opening System (PDOS).
(b) A350-A-70-21-XX-00001-25BA-A: Cleaning and Coating Removal with
Non-Aqueous Liquid Degreasing.
(c) A350-A-70-8X-XX-00001-398A-A: List of Materials - Maintenance
Practices.
(d) A350-A-70-30-61-00001-398A-A: Inspection of Cracks with Fluorescent
Penetrant
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(e) A350-A-71-21-61-00001-310A-A: Detailed Inspection of the Forward
Engine Mount
(f) A350-A-71-13-XX-01001-398A-A:R Closing of the Fan Cowl Doors with the
Power Door Opening System (PDOS).
(2) Overhaul Process Manual (TSD594J):
(a) TASK 70-00-00-100-101 - Overhaul Process 101 - Non-Aqueous Vapour and
Liquid Degreasing.
(b) TASK 70-00-00-200-210 - Overhaul Process 210 - Fluorescent Penetrant
Inspection.
Printed in Great Britain
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2. Material Information
A. Consumables, materials and expendables
Name Quantity Remarks
AMS2644 Type 1, Method D,
Level 2 (1D2) compliant
aerosol penetrant
(Fluorescent, Post
Emulsified, Medium
Sensitivity)
As necessary OMat 650
AMS2644 Type 1, Method D,
Level 4 (1D4) compliant
aerosol penetrant
(Fluorescent, Post
Emulsified, Ultra-high
Sensitivity)
As necessary OMat 652
AMS2644 Type 1, Method A,
Level 3 (1A3) compliant
aerosol penetrant
(Fluorescent, water
washable, High
Sensitivity)
As necessary OMat 632
AMS2644 Form D -
Non-Aqueous Wet Developer
- Aerosol As necessary OMat 617
Acetone based solvent
degreaser As necessary OMat 150
Penetrant 1D2 test panel
(TAM Panel) As necessary OMat 677
Penetrant 1D4 test panel
(TAM Panel) As necessary OMat 677
Penetrant 1A3 test panel
(TAM Panel) As necessary OMat 677
Absorbent Cloths, Lint
Free As necessary OMat 2-101
Printed in Great Britain
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Scotch-brite As necessary OMat 582
Scotch-brite As necessary OMat 583
Sponge type cotton buds As necessary No specific
Disposable plastic nitrile
gloves As necessary No specific
Waterproof, Silicon
Carbide As necessary OMat 5/36
Waterproof, Silicon
Carbide As necessary OMat 5/32
Emery, Polishing Paper As necessary OMat 5/60
Emery, Polishing Paper As necessary OMat 5/54
Printed in Great Britain
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3. Accomplishment Instructions
A. On-wing
WARNING: BE CAREFUL WHEN YOU DO THIS PROCEDURE. OBEY THE EQUIPMENT MANUFACTURER'S
HEALTH AND SAFETY INSTRUCTIONS AND YOUR LOCAL REGULATIONS. INJURY CAN
OCCUR IF YOU DO NOT OBEY THESE INSTRUCTIONS.
WARNING: DO NOT OPERATE AN ULTRAVIOLET SOURCE IF IT DOES NOT HAVE A FILTER OR THE
FILTER DOES NOT HAVE THE CORRECT FIT OR THE FILTER HAS A CRACK.
ULTRAVIOLET RADIATION THAT IS NOT FILTERED CAN CAUSE INJURY TO YOUR EYES
AND SKIN.
WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL
MANUFACTURER INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE IS SHUT
DOWN. THE ENGINE PARTS CAN STAY HOT FOR ALMOST 1 HOUR.
WARNING: DO NOT TOUCH HOT PARTS WITHOUT APPLICABLE GLOVES. HOT PARTS CAN CAUSE AN
INJURY.
CAUTION: THE FLUORESCENT PENETRANT SHOULD BE ONLY APPLIED ON THE INSPECTION
SURFACE. DO NOT LET THE FLUORESCENT PENETRANT GO INTO ANY LOCATION OTHER
THAN THE INSPECTION SURFACE. IF THE FLUORESCENT PENETRANT GOES INTO ANY
LOCATION OTHER THAN THE INSPECTION SURFACE, STOP THE PROCEDURE AND
CONTACT ROLLS-ROYCE FOR FURTHER INSTRUCTIONS.
CAUTION: MAKE SURE THAT ONLY PERSONS WHO ARE APPROVED BY THE APPLICABLE AUTHORITY
DO THESE PROCEDURES. PERSONS WHO ARE NOT APPROVED CAN POSSIBLY GET AN
INCORRECT RESULT, WHICH CAN SUBSEQUENTLY CAUSE COMPONENT FAILURE.
CAUTION: USE ONLY THE CONSUMABLE MATERIALS GIVEN IN THIS TASK. IF YOU DO NOT OBEY
THIS INSTRUCTION, YOU CAN GET AN UNSATISFACTORY RESULT.
CAUTION: THE USE OF HAND HELD AIR AND ELECTRICAL POWER TOOLS IS NOT PERMITTED.
CAUTION: DO NOT LET THE FLUORESCENT PENETRANT REMOVER STAY ON THE SURFACE FOR
MORE THAN THE SPECIFIED TIME. IF THE REMOVER STAYS ON THE SURFACE FOR
MORE THAN THE SPECIFIED TIME, YOU CAN GET AN INCORRECT RESULT. THIS CAN
SUBSEQUENTLY CAUSE COMPONENT FAILURE.
CAUTION: DO NOT USE A TEST PANEL TAM (PSM-5) THAT WAS USED WITH A FLUORESCENT
PENETRANT WITH A DIFFERENT OMAT NUMBER. IF YOU DO, YOU CAN GET AN
INCORRECT RESULT AND THIS CAN SUBSEQUENTLY CAUSE COMPONENT FAILURE
Printed in Great Britain
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CAUTION: IN ORDER TO REDUCE THE POTENTIAL FOR MULTIPLE ENGINE IN-FLIGHT SHUTDOWN,
POWER LOSS, OR OTHER ANOMALY DUE TO MAINTENANCE ERROR, ROLLS-ROYCE
RECOMMENDS THAT OPERATORS AVOID PERFORMING MAINTENANCE ON MULTIPLE
ENGINES INSTALLED ON THE SAME AIRCRAFT AT THE SAME TIME. IF IT IS NOT
POSSIBLE TO AVOID MAINTENANCE ON MORE THAN ONE ENGINE AT THE SAME TIME,
ROLLS-ROYCE RECOMMENDS THAT ADDITIONAL CONTROLS ARE APPLIED IN ORDER TO
ENSURE THAT MAINTENANCE TASKS HAVE BEEN COMPLETED AS DEFINED.
MAINTENANCE GUIDELINES SHOULD BE REVISED, WHERE POSSIBLE, TO PROMOTE
THIS RECOMMENDATION.
(1) Perform the following tasks to gain access (if the engine is not installed
on an aircraft, start the procedure at Step 3.A.(2)) and then inspect the
OGV Outer Mount Ring Assembly (72-35-65, 01-150), in accordance with the
following steps:
(a) Open the fan cowl doors, refer to MP A350-A-71-13-XX-00001-398A-A.
(b) Put the fan case access ladders RRT081482 (or eqivalent) in position.
(2) Perform a detailed inspection of the forward engine mount catcher pin
front-plate (71-21-61, 01-523) and the front mount bracket (71-21-61,
01-500) in accordance with MP A350-A-71-21-61-00001-310A-A.
(3) For the following Fluorescent Penetrant Inspection (FPI) use OMat 650
Penetrant where Penetrant is referred to and use OMat 677 Penetrant 1D2
test panel (TAM panel) where an OMat 677 Penetrant test panel is referred
to unless otherwise instructed.
(4) Prepare the OGV Outer Mount Ring outer rail lug fillets (72-35-65,
01-150), see Figures 1 to 5 for inspection area, for FPI inspection in
accordance with the following steps:
(a) Clean the inspection areas prior to FPI in accordance with the
following steps, refer to MP A350-A-70-21-XX-00001-25BA-A:
Printed in Great Britain
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WARNING: IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND
OBSERVE THE MANUFACTURER'S MATERIAL SAFETY DATA SHEETS FOR
CONSUMABLE MATERIALS. THIS WILL CONTAIN INFORMATION SUCH AS,
HAZARDOUS INGREDIENTS, PHYSICAL/CHEMICAL CHARACTERISTICS,
FIRE, EXPLOSION, REACTIVITY, HEALTH HAZARD DATA, PRECAUTIONS
FOR SAFE HANDLING, USE, CONTROL MEASURES, ENVIRONMENTAL
EFFECTS. IT IS ALSO THE OPERATOR'S RESPONSIBILITY TO TAKE
LOCAL REGULATIONS INTO CONSIDERATION.
CAUTION: TO MAINTAIN THE CLEANLINESS OF THE WIPING SOLVENT, YOU MUST
POUR THE SOLVENT ONTO THE WIPING CLOTH. THE CLOTH MUST NOT
BE DIPPED INTO THE SOLVENT CONTAINER. IF YOU DO NOT OBEY
THIS INSTRUCTION, YOU CAN CAUSE CONTAMINATION OF THE SOLVENT
IN THE CONTAINER.
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 and affect the process performance or produce
unacceptable background.
(i) Put the OMat 150 Acetone based solvent degreaser into a clean
solvent resistant container, refer to MP
A350-A-70-8X-XX-00001-398A-A.
NOTE: Only use a sufficient quantity of solvent to do the
operation.
(ii) Put the solvent from the container on to the OMat 2-101
Absorbent cloth, lint free, refer to MP
A350-A-70-8X-XX-00001-398A-A.
(iii) Do not put the OMat 2-101 Absorbent cloth, lint free into the
solvent in the container. If you do not obey this instruction
you can cause contamination of the solvent in the container,
refer to MP A350-A-70-8X-XX-00001-398A-A.
(iv) Clean the inspection surfaces as shown in Figures 2-5 with a
clean and moist OMat 2-101 Absorbent cloth, lint free.
(v) Ensure that all contaminants have been removed. If necessary
use a clean moist OMat 2-101 Absorbent cloth, lint free again,
until the area becomes clean.
(vi) Allow 10 minutes for the area to be completely dry prior to
penetrant application.
NOTE: You can use a clean absorbent lint free cloth to remove the
unwanted solvent.
Printed in Great Britain
TRENT XWB 72−AK188
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(vii) Safely discard the used materials.
(5) Visually examine the 4-off outer rail lug fillets on the OGV Outer Mount
Ring in accordance with the following limits, refer to Figures 1-5.
(a) Cracks on the outer rail lug fillets:
(i) Reject the OGV outer mount ring.
(ii) Record the damage in Appendix 1.
(b) Corrosion on the outer rail lug fillets:
(i) Reject the OGV outer mount ring.
(ii) Record the damage in Appendix 1.
(c) Dents on the outer rail lug fillets:
(i) Not more than 3 mm diameter and not more than 0.9 mm in depth.
Minimum of 10 mm separation between dents.
Accept.
(ii) Not more than 4.5 mm diameter and not more than 0.9 mm in
depth.  Minimum of 10 mm separation between dents.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 500 flight cycles.
(iii) Not more than 5.5 mm diameter and not more than 0.9 mm in
depth. Minimum of 10 mm separation between dents.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 300 flight cycles.
(iv) Not more than 6.5 mm diameter and not more than 0.9 mm in
depth.  Minimum of 10 mm separation between dents.
Reject the OGV outer mount ring in not more than 50 flight cycles.
Record the damage in Appendix 1.
(v) More than the limits above.
Reject the OGV outer mount ring and record the damage in Appendix
1.
Printed in Great Britain
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(d) Scratches and Nicks on the outer rail lug fillets:
(i) Not more than 0.3 mm in depth and not more than 9 mm in length.
Minimum of 10 mm separation between scratches or nicks.
Accept.
(ii) Not more than 0.6 mm in depth and not more than 9 mm in length.
Minimum of 10 mm separation between scratches or nicks.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 500 flight cycles.
(iii) Not more than 0.8 mm in depth and not more than 9 mm in length.
Minimum of 10 mm separation between scratches or nicks.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 300 flight cycles.
(iv) Not more than 0.9 mm in depth and not more than 9 mm in length.
Minimum of 10 mm separation between scratches or nicks.
Reject the OGV outer mount ring in not more than 50 flight cycles.
Record the damage in Appendix 1.
(v) More than the limits above.
Reject the OGV outer mount ring and record the damage in Appendix
1.
(e) Fretting and Galling on the outer rail lug fillets:
(i) Covering an area of not more than 6.5 mm in width by 6.5 mm in
length and not more than 0.3 mm in depth. Minimum of 10mm
separation between areas of fretting and galling.
Accept
(ii) Covering an area of not more than 6.5 mm in width by 6.5 mm in
length and not more than 0.6 mm in depth. Minimum of 10mm
separation between areas of fretting and galling.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 500 flight cycles.
(iii) Covering an area of not more than 6.5 mm in width by 6.5 mm in
length and not more than 0.8 mm in depth. Minimum of 10mm
separation between areas of fretting and galling.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 300 flight cycles.
Printed in Great Britain
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(iv) Covering an area of not more than 6.5 mm in width by 6.5 mm in
length and not more than 0.9 mm in depth. Minimum of 10mm
separation between areas of fretting and galling.
Reject the OGV outer mount ring in not more than 50 flight cycles.
Record the damage in Appendix 1.
(v) More than the limits above.
Reject the OGV outer mount ring and record the damage in Appendix
1.
(6) The local penetrant processing for this component must be performed in
accordance with the following steps, refer to MP
A350-A-70-30-61-00001-398A-A, Inspection of cracks with Fluorescent
penetrant.
(a) Cover the region of the engine with a dark non-reflective cover in
order to reduce the white light levels.
(b) Prepare the portable Ultraviolet (UV) light source:
(i) Examine the portable UV light source to make sure that it is
serviceable, then set the lamp to the ON position.
(ii) Let the lamp become warm for approximately 10 minutes so that
it is in a stabilized condition.
(iii) Do a check of the light intensity:
NOTE: It may be necessary to mount UV light source in a fixed
position for certain parts of the process e.g. removing
penetrant whilst viewing with mirror under UV illumination.
(1) Hold the lamp at a distance of 0.38 m (15 in.) above the lamp
monitor.
(2) Make sure that there is a minimum light intensity of 1200
microwatts per square centimetre.
(c) Prepare the OMat 677 Penetrant test panel (TAM Panel) for the
inspection:
(i) Remove the OMat 677 Penetrant test panel (TAM Panel) from the
storage container of approved solvent.
(ii) Dry the OMat 677 Penetrant test panel with an OMat 2-101
Absorbent cloth, lint free or a paper-tissue.
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(iii) If the OMat 677 Penetrant test panel (TAM Panel) has been used
before, visually examine it below the portable UV light source.
Make sure that there are no penetrant indications remaining. If
remaining penetrant indications are found, do the following
steps:
(1) Remove the penetrant processing materials from the inspection
surface by wiping with a clean OMat 2-101 Absorbent cloth,
lint free moistened with OMat 150 Acetone based solvent
degreaser.
(2) Clean the Penetrant test panel (TAM Panel) with clean water
to remove the OMat 617 Non-Aqueous Wet Developer.
(3) Dry the Penetrant test panel (TAM Panel) with a clean OMat
2-101 Absorbent cloth, lint free or a paper-tissue.
(4) Soak the Penetrant test panel (TAM Panel) in one of the
approved non-aqueous liquid degreasers for a minimum time of
15 minutes, refer to MP A350-A-70-21-XX-00ZZZ-25BA-A.
(5) Visually examine the Penetrant test panel (TAM Panel) below
the portable UV light source for penetrant indications. If
penetrant indications are found, repeat Steps (6) (c) (iii) 1
- 5.
(d) Apply Penetrant to the inspection areas, refer to Figures 2-5, by
brush or sponge applicator. The penetrant may be dispensed from an
aerosol into a suitable container for brush or sponge application.
Penetrant must comply with manufacturer's shelf life and any unused
penetrant must go to waste.
(e) If an aerosol is not available, it is permissible to use Penetrant
taken from an approved penetrant processing line and fully traceable
with batch numbers as an alternative. The penetrant must be taken from
the processing line on the day of inspection, stored in a clean
container and discarded after the inspection has been completed.
(f) Ensure that the inspection area is fully covered with penetrant with
the aid of the UV light source. Use of an inspection mirror is
required to check coverage where direct line of sight is not available
to the inspector.
(g) Apply Penetrant to the OMat 677 Penetrant test panel (TAM Panel).
(h) Leave the penetrant in contact with the components for 20 minutes.
CAUTION: THE PENETRANT CONTACT TIME MUST NOT EXCEED 1 HOUR. IF IT EXCEEDS
1 HOUR, THEN PENETRANT MUST BE RE-APPLIED AND A FURTHER 5 MINUTES
CONTACT TIME IS ALLOWED.
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(7) After the 20 minutes contact time, remove the excess penetrant from the
inspection surface and the OMat 677 Penetrant test panel (TAM Panel) by
wiping thoroughly with a clean and dry OMat 2-101 Absorbent cloth, lint
free.
CAUTION: DO NOT LET THE FLUORESCENT PENETRANT REMOVER STAY ON THE SURFACE
FOR MORE THAN THE SPECIFIED TIME. IF THE REMOVER STAYS ON THE
SURFACE FOR MORE THAN THE SPECIFIED TIME, YOU CAN GET AN
INCORRECT RESULT. THIS CAN SUBSEQUENTLY CAUSE COMPONENT FAILURE.
CAUTION: USE THE MINIMUM APPLICATION NECESSARY TO ACHIEVE ACCEPTABLE
BACKGROUND FLUORESCENCE AND ENSURE THAT ACETONE IS NOT ALLOWED
TO FLOW ON THE INSPECTION SURFACE.
(8) Whilst illuminating with UV light wipe off the penetrant from the
inspection surface with a clean OMat 2-101 Absorbent cloth, lint free
moistened with OMat 150 Acetone based solvent degreaser. A twice folded (4
layer) lint free cloth is considered to be optimum to achieve this.
(9) Use of inspection mirror to check removal is required where direct line of
sight is not available to the inspector.
(10) Use OMat 2-101 Absorbent cloth, lint free moistened with OMat 150 Acetone
based solvent degreaser to clean the OMat 677 Penetrant test panel (TAM
Panel).
(11) Ensure that all traces of the OMat 150 Acetone based solvent degreaser
have been completely removed by evaporation.
(12) If necessary, repeat the steps (8) to (11) to remove the excess penetrant
from inspection surface and Penetrant test panel (TAM panel). This step
should not be carried out more than 2 times. If the background still
remains after 2 penetrant removal steps (wipes), the part should be
re-cleaned from the start before undergoing repeat FPI technique (repeat
from Step (4) onwards).
(13) Apply a light, even coating of OMat 617 Non-Aqueous Wet Developer from a
sealed aerosol can to the inspection area and OMat 677 Penetrant test
panel (TAM Panel).
(14) Allow 10 minutes contact time for the developer.
(15) Inspect the inspection surface and OMat 677 Penetrant test panel (TAM
Panel) in accordance with the following steps:
(a) Ensure there are no white light sources or fluorescent items
(including clothing) within the inspection area or the inspector's
field of vision.
(b) Do not wear darkened or light sensitive glasses.
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(c) Allow 1 minute for eye adaptation to the darkened area.
(d) Illuminate the OMat 677 Penetrant test panel (TAM Panel) with UV light
at an intensity of no less than 1200 microwatts per square centimetre
in the darkened area.
(e) Inspect the OMat 677 Penetrant test panel (TAM Panel) and check that
the largest indications are visible and match the control photograph
for that individual panel.
(f) Illuminate the inspection surface with UV light at an intensity of no
less than 1200 microwatts per square centimetre in the darkened area.
(g) Examine the Penetrant test panel (TAM Panel) under UV light source for
crack indications. Make sure that there is the correct number of known
indications for the OMat 677 Penetrant test panel used as follows:
(i) If OMat 650 Penetrant was applied, look for three indications
in view.
(ii) If OMat 632 Penetrant was applied, look for four indications in
view.
(iii) If the number of crack indications found is less than that
specified above, do the following steps:
(1) Remove the penetrant processing materials from the inspection
surface by wiping with a clean OMat 2-101 Absorbent cloth,
lint free moistened with OMat 150 Acetone based solvent
degreaser.
(2) Clean the Penetrant test panel (TAM Panel) with clean water
to remove the OMat 617 Non-Aqueous Wet Developer.
(3) Dry the Penetrant test panel (TAM Panel) with a clean OMat
2-101 Absorbent cloth, lint free or a paper-tissue.
(4) Soak the Penetrant test panel (TAM Panel) in one of the
approved non-aqueous liquid degreasers for a minimum time of
15 minutes, refer to MP A350-A-70-21-XX-00ZZZ-25BA-A.
(5) Then on the Penetrant test panel (TAM Panel) only, do the
full penetrant inspection again.
NOTE: A second unsatisfactory result on the Penetrant test
panel (TAM Panel), materials and/or procedure is
unsatisfactory. You must find the cause of the
unsatisfactory result, and then do the full penetrant
inspection of the part and Penetrant test panel (TAM
Panel) again.
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(h) Inspect the OGV Outer Mount Ring Outer Rail Lug Fillets for crack
indications. Use of an inspection mirror is required where direct line
of sight is not available to inspector.
CAUTION: THE USE OF HAND HELD AIR AND ELECTRICAL POWER TOOLS IS NOT
PERMITTED.
(i) Where an indication is highlighted, similar to the example shown in
Figure 6, due to a surface feature (known as redeposited material or
blackspots) it shall be removed by surface cleaning or non-smearing,
hand polishing removal using the following steps (capture all details
of the surface features including whether it was bonded to the parent
material in Appendix 2):
(i) Lightly hand polish using OMat 582 Scotch-brite.
(ii) Where hand polishing using OMat 582 does not remove the surface
features, lightly hand polish using OMat 583 Scotch-brite.
(iii) Where hand polishing using OMat 583 does not remove the surface
features, lightly hand polish using OMat 5/36 Waterproof
Silicon Carbide or OMat 5/60 Emery, polishing paper for no more
than 5 minutes, ensuring that the emery paper is clean and free
from debris at all times. Ensure that the polished surface does
not become hot to the touch.
R
R
R Follow this by lightly hand
polishing with OMat 5/32 Waterproof Silicon Carbide or OMat
5/54 Emery, polishing paper for no more than 5 minutes,
ensuring that the emery paper is clean and free from debris at
all times. Ensure that the polished surface does not become hot
to the touch.
R
R
R
R
(j) If surface cleaning or non-smearing hand polishing removal technique
was carried out in Step (i), then repeat the complete procedure from
step 3. A. (4). If no surface cleaning or non-smearing hand polishing
removal was required, skip step (k) and continue the inspection by
doing step (l).
(k) If any surface features (redeposited material/blackspots) are
identified during the second FPI procedure, evaluate the blackspot
with following criteria:
(i) Single redeposited material/blackspot or clusters of
redeposited material/blackspots not
R
R more than 2.5 mm diameter
and minimum of 10 mm separation between single or clusters ofR
redeposited material/blackspots.
Accept
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(ii) Single redeposited material/blackspot or clusters of
redeposited material/blackspots not
R
R more than 4 mm diameter and
minimum of 10 mm separation between single or clusters ofR
redeposited material/blackspots.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 500 flight cycles.
(iii) Single redeposited material/blackspot or clusters of
redeposited material/blackspots not
R
R more than 5 mm diameter and
minimum of 10 mm separation between single or clusters ofR
redeposited material/blackspots.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 300 flight cycles.
(iv) Single redeposited material/blackspot or clusters of
redeposited material/blackspots not
R
R more than 6 mm diameter and
minimum of 10 mm separation between single or clusters ofR
redeposited material/blackspots.
Reject the OGV outer mount ring in not more than 50 flight cycles.
Record the damage in Appendix 1.
(v) More than the limits above.
Reject the OGV outer mount ring and record the damage in Appendix
1.
(l) Examine the inspection area under UV light source for crack
indications:
(i) If crack indications are found use a MAGNIFYING GLASS POWER 10X
to make sure that there is a defect.
NOTE: When a mirror is being used where direct line of sight is
not available to the inspector, the use of a magnifying
glass power 10X may not be possible and the defect may need
to be assessed using a lower magnification.
(ii) If crack indications can be seen, visually examine the area
below a white light. Use a MAGNIFYING GLASS POWER 15X and
MAGNIFYING GLASS POWER 30X to make sure that there is a defect.
NOTE: When a mirror is being used where direct line of sight is
not available to the inspector, the use of a magnifying
glass power 15X and 30X may not be possible and the defect
may need to be assessed using a lower magnification.
(iii) To aid the evaluation of the indication, the wipe-off technique
can be used as specified in the following steps:
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CAUTION: THE INCORRECT USE OF THE WIPE-OFF TECHINQUE CAN LEAD TO
REMOVAL OF PENETRANT FROM A RELEVANT DISCONTINUITY WHICH
MAY LEAD TO NOT FINDING/REPORTING A RELEVANT
DISCONTINUITY.
(iv) The wipe-off technique must not be used to help clean a part
that has too much background fluorescence. Parts must be
cleaned and processed again if background is excessive or any
processing requirement has not been met.
(v) The wipe-off technique does not need to be used on:
(1) Non-relevant indications e.g. part / assembly interfaces.
(2) Discontinuities that are clearly cause to reject a part.
(vi) To keep the effect of UV fade to a minimum, parts must only be
directly illuminated with a UV inspection light source while
they are being inspected.
(vii) The wipe-off evaluation technique is done after full or local
penetrant process has been completed and must be done with OMat
150 Acetone based solvent degreaser.
(viii) Indications must be wiped one time with a soft artist-type
paint brush or cotton tipped applicator made moist with solvent
OMat 150 Acetone based solvent degreaser. Indications from
casting porosity/shrinkage can be wiped a maximum of two times
in one direction. Do not permit the solvent to flow or run over
the surface. This can best be achieved by pressing excess
solvent from the brush or cotton tipped applicator prior to
wipe-off. If this is not done and solvent flows over the
indication the part must be cleaned and then the FPI process
started again.
(ix) When the bleedout from a discontinuity is seen immediately
after it is wiped, stop the process and go to Step (16).
(x) When the bleedout from a discontinuity is not seen immediately
after it is wiped, apply OMat 617 Non-Aqueous Wet Developer to
the area.
NOTE: For OMat 617 Non-Aqueous Wet Developer, allow 5 minutes
minimum of development time.
(xi) If the indication does not bleed out after development time,
view the area with white light to see if there was a relevant
cause of the original indication. A visual aid with a
magnification of up to 10X must be used.
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(xii) All evaluations must be completed in less than 1 hour from when
the developer was applied.
(xiii) If the cause of the bleedout is found, go to Step (16).
(xiv) If the bleedout forms a relevant indication but its cause
cannot be found, remove the developer and then repeat procedure
from Step (4) onwards.
(16) If there are any cracks or crack indications on the inspection surface:
(a) Reject the OGV outer mount ring.
(b) Record the damage details in Appendix 1.
(17) If there is damage observed during the Fluorescent Penetrant Inspection
which was not observed during the visual inspection in Step 3.A.(5),
assess the damage against the limits defined in Step 3.A.(5).
(18) If fretting and galling was observed and accepted in Step 3.A.(5)(e) but
the background fluorescence is too high to assess the region for cracks
repeat Steps 3.A. (4) to (17) only using OMat 632 penetrant where
Penetrant is referred to. Where OMat 677 Penetrant test panel (TAM panel)
is referred to, ensure that a Penetrant 1A3 test panel (TAM panel) which
has only been used with OMat 632 is used.
(19) 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 Absorbent cloth, lint free moistened with OMat 150
Acetone based solvent degreaser.
(20) Clean the Penetrant test panel (TAM Panel) in accordance with the
following steps.
(a) Clean the Penetrant test panel (TAM Panel) with clean water to remove
the OMat 617 Non-Aqueous Wet Developer.
(b) Dry the Penetrant test panel (TAM Panel) with a clean OMat 2-101
Absorbent cloth, lint free or a paper-tissue.
(c) Soak the Penetrant test panel (TAM Panel) in one of the approved
non-aqueous liquid degreasers for a minimum time of 15 minutes, refer
to MP A350-A-70-21-XX-00ZZZ-25BA-A.
(d) Visually examine the Penetrant test panel (TAM Panel) below the
portable UV light source for penetrant indications.
(e) If penetrant indications are found, repeat step (20).
(21) Make sure that the work area is clean and clear of tools and other items.
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(22) If the engine is not installed on an aircraft go to Step 3.A.(24). If the
engine is installed on an aircraft remove the fan case access ladders
RRT081482 (or equivalent).
(23) Close the fan cowl doors; refer to MP A350-A-71-13-XX-01001-398A-A.R
(24) Complete and return Appendix 1, or similar form, to your Rolls-Royce
Airline Support Team representative.
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B. In-shop
WARNING: BE CAREFUL WHEN YOU DO THIS PROCEDURE. OBEY THE EQUIPMENT MANUFACTURER'S
HEALTH AND SAFETY INSTRUCTIONS AND YOUR LOCAL REGULATIONS. INJURY CAN
OCCUR IF YOU DO NOT OBEY THESE INSTRUCTIONS.
WARNING: DO NOT OPERATE AN ULTRAVIOLET SOURCE IF IT DOES NOT HAVE A FILTER OR THE
FILTER DOES NOT HAVE THE CORRECT FIT OR THE FILTER HAS A CRACK.
ULTRAVIOLET RADIATION THAT IS NOT FILTERED CAN CAUSE INJURY TO YOUR EYES
AND SKIN.
WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL
MANUFACTURER INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
CAUTION: THE FLUORESCENT PENETRANT SHOULD BE ONLY APPLIED ON THE INSPECTION
SURFACE. DO NOT LET THE FLUORESCENT PENETRANT GO INTO ANY LOCATION OTHER
THAN THE INSPECTION SURFACE. IF THE FLUORESCENT PENETRANT GOES INTO ANY
LOCATION OTHER THAN THE INSPECTION SURFACE, STOP THE PROCEDURE AND
CONTACT ROLLS-ROYCE FOR FURTHER INSTRUCTIONS.
CAUTION: THE USE OF HAND HELD AIR AND ELECTRICAL POWER TOOLS IS NOT PERMITTED.
CAUTION: MAKE SURE THAT ONLY PERSONS WHO ARE APPROVED BY THE APPLICABLE AUTHORITY
DO THESE PROCEDURES. PERSONS WHO ARE NOT APPROVED CAN POSSIBLY GET AN
INCORRECT RESULT, WHICH CAN SUBSEQUENTLY CAUSE COMPONENT FAILURE.
CAUTION: USE ONLY THE CONSUMABLE MATERIALS GIVEN IN THIS TASK. IF YOU DO NOT OBEY
THIS INSTRUCTION, YOU CAN GET AN UNSATISFACTORY RESULT.
CAUTION: DO NOT LET THE FLUORESCENT PENETRANT REMOVER STAY ON THE SURFACE FOR
MORE THAN THE SPECIFIED TIME. IF THE REMOVER STAYS ON THE SURFACE FOR
MORE THAN THE SPECIFIED TIME, YOU CAN GET AN INCORRECT RESULT. THIS CAN
SUBSEQUENTLY CAUSE COMPONENT FAILURE.
CAUTION: DO NOT USE A TEST PANEL TAM (PSM-5) THAT WAS USED WITH A FLUORESCENT
PENETRANT WITH A DIFFERENT OMAT NUMBER. IF YOU DO, YOU CAN GET AN
INCORRECT RESULT AND THIS CAN SUBSEQUENTLY CAUSE COMPONENT FAILURE
(1) For the following Fluorescent Penetrant Inspection (FPI), use OMat 652
Penetrant where Penetrant is referred to and use OMat 677 Penetrant 1D4
test panel (TAM panel) where an OMat 677 Penetrant test panel is referred
to unless otherwise instructed.
(2) Prepare the Ring, Assy OGV Outer Mount outer rail fillets (72-35-46,
01-150), see Figures 1 to 5 for inspection area, for Fluorescent Penetrant
Inspection in accordance with the following steps.
(a) Clean the inspection areas prior to FPI in accordance with the
following steps, refer to TSD594J OP 101 Section 9. (Subtask
70-00-00-110-101-A03).
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WARNING: IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND
OBSERVE THE MANUFACTURER'S MATERIAL SAFETY DATA SHEETS FOR
CONSUMABLE MATERIALS. THIS WILL CONTAIN INFORMATION SUCH AS,
HAZARDOUS INGREDIENTS, PHYSICAL/CHEMICAL CHARACTERISTICS,
FIRE, EXPLOSION, REACTIVITY, HEALTH HAZARD DATA, PRECAUTIONS
FOR SAFE HANDLING, USE, CONTROL MEASURES, ENVIRONMENTAL
EFFECTS. IT IS ALSO THE OPERATOR'S RESPONSIBILITY TO TAKE
LOCAL REGULATIONS INTO CONSIDERATION.
CAUTION: TO MAINTAIN THE CLEANLINESS OF THE WIPING SOLVENT, YOU MUST
POUR THE SOLVENT ONTO THE WIPING CLOTH. THE CLOTH MUST NOT
BE DIPPED INTO THE SOLVENT CONTAINER. IF YOU DO NOT OBEY
THIS INSTRUCTION, YOU CAN CAUSE CONTAMINATION OF THE SOLVENT
IN THE CONTAINER.
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 and affect the process performance or produce
unacceptable background.
(i) Apply OMat 150 Acetone based solvent degreaser to a clean OMat
2-101 Absorbent cloth, lint free.
(ii) Clean the inspection surfaces as shown in Figures 2-5 with a
clean and moist OMat 2-101 Absorbent cloth, lint free.
(iii) Ensure that all contaminants have been removed. If necessary
repeat the swabbing using fresh lint free cloth and solvent
until the area is clean and free of soil and grease.
(iv) Allow 10 minutes for the area to be completely dry prior to
penetrant application.
NOTE: You can use a clean lint free cloth to remove the unwanted
solvent.
(v) Safely discard the used materials.
(3) Visually examine the 4-off outer rail lug fillets on the Ring, Assy OGV
Outer Mount in accordance with the following limits, refer to Figures 1-5.
(a) Cracks on the outer rail lug fillets:
(i) Reject the OGV outer mount ring.
(ii) Record the damage in Appendix 1.
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(b) Corrosion on the outer rail lug fillets:
(i) Reject the OGV outer mount ring.
(ii) Record the damage in Appendix 1.
(c) Dents on the outer rail lug fillets:
(i) Not more than 3 mm diameter and not more than 0.9 mm in depth.
Minimum of 10 mm separation between dents.
Accept.
(ii) Not more than 4.5 mm diameter and not more than 0.9 mm in
depth. Minimum of 10 mm separation between dents.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 500 flight cycles.
(iii) Not more than 5.5 mm diameter and not more than 0.9 mm in
depth. Minimum of 10 mm separation between dents.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 300 flight cycles.
(iv) More than the limits above.
Reject the OGV outer mount ring and record the damage in Appendix
1.
(d) Scratches and Nicks on the outer rail lug fillets:
(i) No more than 0.3 mm in depth and not more than 9 mm in length.
Minimum of 10 mm separation between scratches or nicks.
Accept.
(ii) No more than 0.6 mm in depth and not more than 9 mm in length.
Minimum of 10 mm separation between scratches or nicks.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 500 flight cycles.
(iii) Not more than 0.8 mm in depth and not more than 9 mm in length.
Minimum of 10 mm separation between scratches or nicks.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 300 flight cycles.
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(iv) More than the limits above.
Reject the OGV outer mount ring and record the damage in Appendix
1.
(e) Fretting and Galling on the outer rail lug fillets:
(i) Covering an area of not more than 6.5 mm in width by 6.5 mm in
length and not more than 0.3 mm in depth. Minimum of 10mm
separation between areas of fretting and galling.
Accept.
(ii) Covering an area of not more than 6.5 mm in width by 6.5 mm in
length and not more than 0.6 mm in depth. Minimum of 10mm
separation between areas of fretting and galling.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 500 flight cycles.
(iii) Covering an area of not more than 6.5 mm in width by 6.5 mm in
length and not more than 0.8 mm in depth. Minimum of 10mm
separation between areas of fretting and galling.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in not more than 300 flight cycles.
(iv) More than the limits above.
Reject the OGV outer mount ring and record the damage in Appendix
1.
(4) The local penetrant processing for this component must be performed in
accordance with the following steps, refer to TSD 594J OP210 (TASK
70-00-00-200-210) - Fluorescent Penetrant Inspection.
(a) Cover the region of the engine with a dark non-reflective cover in
order to reduce the white light levels.
(b) Prepare the portable Ultraviolet (UV) light source:
(i) Examine the portable UV light source to make sure that it is
serviceable, then set the lamp to the ON position.
(ii) Let the lamp become warm for approximately 10 minutes so that
it is in a stabilized condition.
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(iii) Do a check of the light intensity:
NOTE: It may be necessary to mount UV light source in a fixed
position for certain parts of the process e.g. removing
penetrant whilst viewing with mirror under UV illumination.
(1) Hold the lamp at a distance of 0.38 m (15 in.) above the lamp
monitor.
(2) Make sure that there is a minimum light intensity of 1200
microwatts per square centimetre.
(c) Prepare the OMat 677 Penetrant test panel (TAM Panel) for the
inspection:
(i) Remove the OMat 677 Penetrant test panel (TAM Panel) from the
storage container of approved solvent.
(ii) Dry the OMat 677 Penetrant test panel with an OMat 2-101
Absorbent cloth, lint free or a paper-tissue.
(iii) If the OMat 677 Penetrant test panel (TAM Panel) has been used
before, visually examine it below the portable UV light source.
Make sure that there are no penetrant indications remaining. If
remaining penetrant indications are found, do the following
steps:
(1) Remove the penetrant processing materials from the inspection
surface by wiping with a clean OMat 2-101 Absorbent cloth,
lint free moistened with OMat 150 Acetone based solvent
degreaser.
(2) Clean the Penetrant test panel (TAM Panel) with clean water
to remove the OMat 617 Non-Aqueous Wet Developer.
(3) Dry the Penetrant test panel (TAM Panel) with a clean OMat
2-101 Absorbent cloth, lint free or a paper-tissue.
(4) Soak the Penetrant test panel (TAM Panel) in one of the
approved non-aqueous liquid degreasers for a minimum time of
15 minutes, refer to Overhaul Process Manual (TSD594J) TASK
70-00-00-100-101.
(5) Visually examine the Penetrant test panel (TAM Panel) below
the portable UV light source for penetrant indications. If
penetrant indications are found, repeat Steps (4) (c) (iii) 1
- 5.
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(d) Apply Penetrant to the inspection areas, refer to Figures 2-5, by
brush or sponge applicator. The penetrant may be dispensed from an
aerosol into a suitable container for brush or sponge application.
Penetrant must comply with manufacturer's shelf life and any unused
penetrant must go to waste.
(e) If an aerosol penetrant is not available, it is permissible to use
Penetrant taken from an approved penetrant processing line and fully
traceable with batch numbers as an alternative. The penetrant must be
taken from the processing line on the day of inspection, stored in a
clean container and discarded after the inspection has been completed.
(f) Ensure that the inspection area is fully covered with penetrant with
the aid of a UV light source. Use of an inspection mirror is required
to check coverage where direct line of sight is not available to the
inspector.
(g) Apply Penetrant to the OMat 677 Penetrant test panel (TAM Panel).
(h) Leave the penetrant in contact with the components for 20 minutes.
CAUTION: THE PENETRANT CONTACT TIME MUST NOT EXCEED 1 HOUR. IF IT EXCEEDS
1 HOUR, THEN PENETRANT MUST BE RE-APPLIED AND A FURTHER 5 MINUTES
CONTACT TIME IS ALLOWED.
(5) After the 20 minutes contact time, remove the excess penetrant from the
inspection surface and the OMat 677 Penetrant test panel (TAM Panel) by
wiping thoroughly with a clean and dry OMat 2-101 Absorbent cloth, lint
free.
CAUTION: DO NOT LET THE FLUORESCENT PENETRANT REMOVER STAY ON THE SURFACE
FOR MORE THAN THE SPECIFIED TIME. IF THE REMOVER STAYS ON THE
SURFACE FOR MORE THAN THE SPECIFIED TIME, YOU CAN GET AN
INCORRECT RESULT. THIS CAN SUBSEQUENTLY CAUSE COMPONENT FAILURE.
CAUTION: USE THE MINIMUM APPLICATION NECESSARY TO ACHIEVE ACCEPTABLE
BACKGROUND FLUORESCENCE AND ENSURE THAT ACETONE IS NOT ALLOWED
TO FLOW ON THE INSPECTION SURFACE.
(6) Whilst illuminating with UV light, wipe off the penetrant from the
inspection surface with a clean OMat 2-101 Absorbent cloth, lint free
moistened with OMat 150 Acetone based solvent degreaser. A twice folded (4
layer) lint free cloth is considered to be optimum to achieve this.
(7) Use of inspection mirror to check removal is required where direct line of
sight is not available to the inspector.
(8) Use OMat 2-101 Absorbent cloth, lint free moistened with OMat 150 Acetone
based solvent degreaser to clean the OMat 677 Penetrant test panel (TAM
Panel).
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(9) Ensure that all traces of the OMat 150 Acetone based solvent degreaser
have been completely removed by evaporation.
(10) If necessary, repeat the steps (6) to (9) to remove the excess penetrant
from inspection surface and Penetrant test panel (TAM panel). This step
should not be carried out more than 2 times. If the background still
remains after 2 penetrant removal steps (wipes), the part should be
re-cleaned from the start before undergoing repeat FPI technique (repeat
from Step (2) onwards).
(11) Apply a light, even coating of OMat 617 Non-Aqueous Wet Developer from a
sealed aerosol can to the inspection area and OMat 677 Penetrant test
panel (TAM Panel).
(12) Allow 10 minutes contact time for the developer.
(13) Inspect the inspection surface and Penetrant test panel (TAM Panel) in
accordance with the following steps, refer to TSD594J OP210 (TASK
70-00-00-200-210) - Fluorescent Penetrant Inspection.
(a) Ensure there are no white light sources or fluorescent items
(including clothing) within the inspection area or the inspector's
field of vision.
(b) Do not wear darkened or light sensitive glasses.
(c) Allow 1 minute for eye adaptation to the darkened area.
(d) Illuminate the OMat 677 Penetrant test panel (TAM Panel) with UV light
at an intensity of no less than 1200 microwatts per square centimetre
in the darkened area.
(e) Inspect the OMat 677 Penetrant test panel (TAM Panel) and check that
the largest indications are visible and match the control photograph
for that individual panel.
(f) Illuminate the inspection surface with UV light at an intensity of no
less than 1200 microwatts per square centimetre in the darkened area.
(g) Examine the Penetrant test panel (TAM Panel) under UV light-source for
crack indications. Make sure that there is the correct number of known
indications for the OMat 677 Penetrant test panel used as follows:
(i) If OMat 652 Penetrant was applied, look for five indications in
view, refer to TSD 594J OP210 (TASK 70-00-00-200-210) -
Fluorescent Penetrant Inspection.
(ii) If OMat 650 Penetrant was applied, look for three indications
in view, refer to TSD 594J OP210 (TASK 70-00-00-200-210) -
Fluorescent Penetrant Inspection.
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(iii) If OMat 632 Penetrant was applied, look for four indications in
view, refer to TSD 594J OP210 (TASK 70-00-00-200-210) -
Fluorescent Penetrant Inspection.
(iv) If the number of crack indications found is less than that
specified above, do the following steps:
(1) Remove the penetrant processing materials from the inspection
surface by wiping with a clean OMat 2-101 Absorbent cloth,
lint free moistened with OMat 150 Acetone based solvent
degreaser.
(2) Clean the Penetrant test panel (TAM Panel) with clean water
to remove the OMat 617 Non-Aqueous Wet Developer.
(3) Dry the Penetrant test panel (TAM Panel) with a clean OMat
2-101 Absorbent cloth, lint free or a paper-tissue.
(4) Soak the Penetrant test panel (TAM Panel) in one of the
approved non-aqueous liquid degreasers for a minimum time of
15 minutes, refer to Overhaul Process Manual (TSD594J) TASK
70-00-00-100-101.
(5) Then on the Penetrant test panel (TAM Panel) only, do the
full penetrant inspection again.
NOTE: A second unsatisfactory result on the Penetrant test
panel (TAM Panel), materials and/or procedure is
unsatisfactory. You must find the cause of the
unsatisfactory result, and then do the full penetrant
inspection of the part and Penetrant test panel (TAM
Panel) again.
(h) Inspect the Ring, Assy OGV Outer Mount Outer Rail Lug Fillets for
crack indications. Use of inspection mirror is required where direct
line of sight is not available to inspector.
CAUTION: THE USE OF HAND HELD AIR AND ELECTRICAL POWER TOOLS IS NOT
PERMITTED.
(i) Where an indication is highlighted, similar to the example shown in
Figure 6, due to a surface feature (known as redeposited material or
blackspots) it shall be removed by surface cleaning or non-smearing
hand polishing removal using the following steps (capture all details
of the surface features including whether it was bonded to the parent
material in Appendix 2):
(i) Lightly hand polish using OMat 582 Scotch-brite.
(ii) Where hand polishing using OMat 582 does not remove the surface
features, lightly hand polish using OMat 583 Scotch-brite.
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(iii) Where hand polishing using OMat 583 does not remove the surface
features, lightly hand polish using OMat 5/36 Waterproof
Silicon Carbide or Omat 5/60 Emery, polishing paper for no more
than 5 minutes, ensuring that the emery paper is clean and free
from debris at all times. Ensure that the polished surface does
not become hot to the touch.
R
R
R Follow this by lightly hand
polishing with OMat 5/32 Waterproof Silicon Carbide or OMat
5/54 Emery, polishing paper for no more than 5 minutes,
ensuring that the emery paper is clean and free from debris at
all times. Ensure that the polished surface does not become hot
to the touch.
R
R
R
R
(j) If surface cleaning or non-smearing hand polishing removal technique
was carried out in Step (i), then repeat the complete procedure from
step 3. B. (2). If no surface cleaning or non-smearing hand polishing
removal was required, skip step (k) and continue the inspection by
doing step (l).
(k) If any surface features (redeposited material/ blackspots) are
identified during the second FPI procedure, evaluate the blackspot
with following criteria:
(i) Single redeposited material/blackspot or clusters of
redeposited material/blackspots not
R
R more than 2.5 mm diameter
and minimum of 10 mm separation between single or clusters ofR
redeposited material/blackspots.
Accept.
(ii) Single redeposited material/blackspot or clusters of
redeposited material/blackspots not
R
R more than 4 mm diameter and
minimum of 10 mm separation between single or clusters ofR
redeposited material/blackspots.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in no more than 500 flight cycles.
(iii) Single redeposited material/blackspot or clusters of
redeposited material/blackspots not
R
R more than 5 mm diameter and
minimum of 10 mm separation between single or clusters ofR
redeposited material/blackspots.
Repeat the inspections defined in NMSB 72-AK188 in their entirety
in no more than 300 flight cycles.
(iv) More than the limits above.
Reject the OGV outer mount ring and record the damage in Appendix
1.
Printed in Great Britain
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(l) Examine the inspection area under UV light source for crack
indications:
(i) If crack indications are found, use a MAGNIFYING GLASS POWER
10X to make sure that there is a defect.
NOTE: When a mirror is being used where direct line of sight is
not available to the inspector, the use of a magnifying
glass power 10X may not be possible and the defect may need
to be assessed using a lower magnification.
(ii) If crack indications can be seen, visually examine the area
below a white light. Use a MAGNIFYING GLASS POWER 15X and
MAGNIFYING GLASS POWER 30X to make sure that there is a defect.
NOTE: When a mirror is being used where direct line of sight is
not available to the inspector, the use of a magnifying
glass power 15X and 30X may not be possible and the defect
may need to be assessed using a lower magnification.
(iii) To aid the evaluation of the indication, the wipe-off technique
can be used as specified in TSD594J OP 210 SUBTASK
70-00-00-230-210-078.
(14) If there are any cracks or crack indications on the inspection surface:
(a) Reject the OGV outer mount ring.
(b) Record the damage in Appendix 1.
(15) If there is damage observed during the Fluorescent Penetrant Inspection
which was not observed during the visual inspection in Step 3.B.(3),
assess the damage against the limits defined in Step 3.B.(3).
(16) If fretting and galling was observed and accepted in Step 3.B.(3)(e) but
the background fluorescence is too high to assess the region for cracks
repeat Steps 3.B. (2) to (16) only using OMat 650 penetrant where
Penetrant is referred to. Where OMat 677 Penetrant test panel (TAM panel)
is referred to, ensure that a Penetrant 1D2 test panel (TAM panel) which
has only been used with OMat 650 is used.
(17) If after Step (16) the background fluorescence is still too high to assess
the region for cracks repeat Steps 3.B. (2) to (16) only using OMat 632
penetrant where Penetrant is referred to. Where OMat 677 Penetrant test
panel (TAM panel) is referred to, ensure that a Penetrant 1A3 test panel
(TAM panel) which has only been used with OMat 632 is used.
(18) 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 Absorbent cloth, lint free moistened with OMat 150
Acetone based solvent degreaser.
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(19) Clean the Penetrant test panel (TAM Panel) used in accordance with the
following steps, refer to TSD 594J OP210 (TASK 70-00-00-200-210) -
Fluorescent Penetrant Inspection.
(a) Clean the Penetrant test panel (TAM Panel) with clean water to remove
the OMat 617 Non-Aqueous Wet Developer.
(b) Dry the Penetrant test panel (TAM Panel) with a clean OMat 2-101
Absorbent cloth, lint free or a paper-tissue.
(c) Soak the Penetrant test panel (TAM Panel) in one of the approved
non-aqueous liquid degreasers for a minimum time of 15 minute.
(d) Visually examine the Penetrant test panel (TAM Panel) below the
portable UV light source for penetrant indications.
(e) If penetrant indications are found, repeat step (19).
(20) Make sure that the work area is clean and clear of tools and other items.
(21) Complete and return Appendix 1, or similar form, to your Rolls-Royce
Overhaul Support Team representative.
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### Page 36

dex0002097
FORWARD ENGINE
MOUNT RAILS
A
B
B
A
B
TYPICAL 2 LOCATIONS
OUTER RAIL
LUG FILLET
OUTER RAIL LUG
A
TYPICAL 2 LOCATIONS
OUTER RAIL
LUG FILLET
OUTER RAIL LUG
Figure 1 - OGV Outer Mount Ring - Inspection Locations
Printed in Great Britain
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Figure 2 - Front Mount Ring with Mount Assembly showing 4-off OGV Outer Mount Ring
Outer Rail Lug Fillets Inspection Areas
Printed in Great Britain
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Figure 3 - Definition of Extent of Inspection Areas
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dex0002297
E
D
20.00 mm
(0.787 in)
20.00 mm
(0.787 in)
10.00 mm
(0.394 in)
Figure 4 - Definition of Extent of Inspection Areas
Printed in Great Britain
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### Page 40 (OCR)

ROYCE  Rolls-Royce  TRENT XWB SERIES  SERVICE BULLETIN
Printed in Great Britain
Inspection Areas:
Fillet radius
including
circumferential
and axial extents
and pockets
(green).
Inspect starboard
and port lugs on
forward and aft
rails- 4-off lug
inspections.
Figure 5 - Areas required to undergo FPI processing and inspection
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© Rolls-Royce p/c

### Page 41

Figure 6 - Surface feature (known as redeposited material or blackspot) shown in the
pre and post wipe-off condition.
Printed in Great Britain
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This form (or similar) to be completed for every OGV Outer Mount Ring inspected.
Results to be sent to Rolls-Royce via your Rolls-Royce Representative.
Feedback Sheet NMSB 72-AK188
Overhaul Base / Operator
Date of Inspection
Engine Serial Number
Engine Hours Since New
Engine Cycles Since New
OGV Outer Mount Ring Part Number
(Identification: Outer circumference of
the mount ring, right angle to center
catcher lug position)
Inspection result (accept/reject) and if applicable
details on the reason for rejection
Inspection of Lug 1R
(Forward port)R
(refer to Figure 2)
Inspection of Lug 2R
(Rearward port)R
(refer to Figure 2)
Inspection of Lug 3R
(Forward starboard)R
(refer to Figure 2)
Inspection of Lug 4R
(Rearward starboard)R
(refer to Figure 2)
APPENDIX 1
Printed in Great Britain
TRENT XWB 72−AK188
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Attach photographic
evidence of damages
if any.
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This form (or similar) to be completed for every surface feature (redeposited
material/blackspot) identified during the OGV Outer Mount Ring inspection.
Results to be sent to Rolls-Royce via your Rolls-Royce Representative
Details of surface feature (redeposited material/blackspot) identified during
NMSB 72-AK188
Overhaul Base / Operator
Date of Inspection
Engine Serial Number
Engine Hours Since New
Engine Cycles Since New
OGV Outer Mount Ring Part Number
(Identification: Outer circumference of
the mount ring, right angle to center
catcher lug position)
Remarks
Has a surface feature (redeposited
material/blackspot appeared during
inspection.
Yes / No
If Yes, was the feature removable? Yes / No
If Yes, were the features removed and
what removal method was carried out?
Details of surface feature (redeposited
material/blackspot) identified during
second FPI procedure.
Number of occurrences:
Locations:
Diameter of feature:
Add the photographic evidence of
redeposited material/blackspots which
remained during second FPI procedure,
if any.
APPENDIX 2
Printed in Great Britain
TRENT XWB 72−AK188
Appendix 2 - Page 1 of 1
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