# Rolls-Royce Non-Modification Service Bulletin RB.211-72-AL191: No revision named

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- Document: [Rolls-Royce Non-Modification Service Bulletin RB.211-72-AL191](https://openairdocs.org/service-documents/rolls-royce/rb211-72-al191.md)
- Title as filed: RRD NMSB RB_72-AL191 (reduced sz)
- Pages: 78
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This document transmits the Initial Issue of Service Bulletin RB211-72-AL191
Bulletin Initial Issue
Remove Incorporate Reason for change
Pages 1 to 74 of the
Service Bulletin
Initial Issue
P.O. Box 31, Derby
DE24 8BJ, UK
Tel: +44 (0) 1332 242424
This Rolls-Royce Technical Publication is
subject to export control as follows:
Jurisdiction: UK
Export Classification: PL9009c
The technical information contained in this document has been approved under the authority of - See Planning
Information, Approval.
Date: May 30, 2025
RB211 TRENT 700 SERIES PROPULSION SYSTEMS NON-MODIFICATION SERVICE BULLETIN
ALERT
RB211−72−AL191
Transmittal - Page 1 of 4
CHECK THAT ALL PREVIOUS TRANSMITTALS HAVE BEEN INCORPORATED
If any have not been received please advise customersupport@rolls-royce.com.
© 2025 Rolls-Royce plc
P   U   B   L   I   C   A   T   I   O   N          T   R   A   N   S   M   I   T   T   A   L
ALERT

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LIST OF EFFECTIVE PAGES
The effective pages to this Service Bulletin are as follows:
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ENGINE - LP COMPRESSOR - INSPECTION OF LP COMPRESSOR BLADES - NON-MODIFICATION
SERVICE BULLETIN - NON - MOD.72-AL191
1. Planning Information
A. Effectivity
Airbus A330
RB211 TRENT 768-60, TRENT 768-60/15, TRENT 768-60/16 Engines
RB211 TRENT 772-60, TRENT 772-60/15, TRENT 772-60/16 Engines
RB211 TRENT 772B-60, TRENT 772B-60/15, TRENT 772B-60/16 Engines
RB211 TRENT 772C-60, TRENT 772C-60/15, TRENT 772C-60/16 Engines.
B. Reason
(1) Problem
Following in-service Low Pressure (LP) compressor (fan) blade release events it is
recommended that an in-service inspection (ultrasonic) is undertaken to mitigate against release
events. If an ultrasonic inspection is missed, improperly performed, or performed with incorrectly
maintained equipment; the effectiveness of the inspection will be reduced and less likely to
detect sub-surface anomalies that have the potential to propagate and result in the release of LP
compressor blade material.
The ultrasonic inspection is capable of detecting sub-surface anomalies in the LP compressor
blade aerofoil. This inspection is available for Trent 700 LP compressor blades at shop visit but
the intervals between shop visits are too large to only use shop visit opportunities therefore
on-going in-service repeat inspections are required.
(2) Safety Intent
The safety intent of this SB is to detect LP compressor blade sub-surface anomalies, prior to the
anomalies developing into larger defects that could affect the integrity of the LP compressor
blade.
C. Description
(1) This Non-Modification Service Bulletin (NMSB) is issued to instruct an ultrasonic inspection of
LP compressor blades aerofoil.
Accomplishment of this NMSB must be recorded against the individual blades and compliance,
blades serial numbers and associated blade lives (Time Since New (TSN)/ Cycles Since New
(CSN)) logged with your assigned Rolls-Royce Airline Support Team using the proforma in
Appendix 2 or 9 as applicable.
(2) The accomplishment instructions for ultrasonic inspection of LP compressor blades is dependent
on where the inspection is undertaken as follows:
(
a) Accomplishment instructions for removal and installation of LP compressor blades from an
engine on-wing or spare engine for inspection in accordance with Section 3.D., refer to
Section 3.B.
(b) Accomplishment instructions for C-Scan inspection of LP compressor blades, removed
from an engine in-shop, refer to Section 3.C.
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(c) Accomplishment instructions for phased array (water-coupled procedure) inspection of LP
compressor blades, removed from an engine on-wing or spare engine, refer to Section
3.D.
NOTE: Section 3.B. is only applicable if blades are to be inspected in accordance with
Section 3.D. For Section 3.C., blades are removed and installed in accordance
with Engine Manual procedures.
D. Compliance
ALERT
This Non-Modification Service Bulletin is anticipated to be the subject of an EASA/FAA Airworthiness
Directive.
(1) LP compressor blade inspection shall be performed in accordance with Section 3.C. or 3.D. of
this Non-Modification Service Bulletin in the below defined timescales for the identified LP
compressor blades. The LP compressor blade life and life since C-Scan are as on Jul. 1/2025.
The inspections are required to be accomplished within the defined dates or cycles from Jul.
1/2025:
Criteria Inspection
(a) All LP compressor blades listed in
Appendix 1
Do an inspection in 400 cycles or before
Dec. 31/2025 or no later than 1,200
cycles since last inspection, whichever is
sooner
(b) On all LP compressor blade standards
with a life since last C-scan inspection is
greater than 6,000 cycles
Do an inspection in 400 cycles or before
Dec. 31/2025 or no later than 1,200
cycles since last inspection, whichever is
sooner
(c) On all LP compressor blade standards
not inspected with C-scan and life since
new is greater than 6,000 cycles
Do an inspection in 400 cycles or before
Dec. 31/2025 or no later than 1,200
cycles since last inspection, whichever is
sooner
(d) On all LP compressor blade standards
with a life since last C-scan inspection is
between 2,400 and 6,000 cycles
Do an inspection in 800 cycles or before
Jun. 30/2026 or no later than 1,200
cycles since last inspection, whichever is
sooner
(e) On all LP compressor blade standards
not inspected with C-scan and life since
new is between 2,400 and 6,000 cycles
Do an inspection in 800 cycles or before
Jun. 30/2026 or no later than 1,200
cycles since last inspection, whichever is
sooner
(f) On all LP compressor blade standards
with a life since last C-scan inspection is
less than 2,400 cycles
Do an inspection within 1,200 cycles
since last inspection
(g) On all LP compressor blade standards
not inspected with C-scan and life since
new is less than 2,400 cycles
Do an inspection within 1,200 cycles
since last inspection
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Criteria Inspection
(h) LP compressor blades that are not in
service and have no flights flown since
Jul. 1/2025, due to which the
inspections defined in criteria 1.D.(1)(a)
to 1.D.(1)(e) cannot be complied with
Do an inspection within 50 cycles from
the LP compressor blade first return to
service
(2) For operators who conduct Standard Operations (as defined in Time Limits Manual (TLM) Task
05-00-01)
This NMSB should be accomplished on all LP compressor blades to part numbers FW23643,
FW23741, FW23744, KH23403, KH23404 or LV11570 and is in two parts as follows:
(
a) Part 1 - Initial Inspection
[1] Do an inspection as defined in 1.D.(1).
NOTE: Last inspections were in accordance with the Accomplishment Instructions
of NMSB 72-G702 or NMSB 72-G872 or NMSB 72-H311 or NMSB
72-AH465 or EM Task 72-31-11 or Aircraft Maintenance Manual (AMM)
Task 72-31-41.
(
b) Part 2 - Repeat Inspection
[1] Re-inspect at an interval that does not exceed 1,200 cycles since last inspection in
accordance with this NMSB.
NOTE: Last inspections were in accordance with the Accomplishment Instructions
of NMSB 72-AL191.
(3) For operators who conduct Non-Standard Operations (as defined in TLM Task 05-00-01).
This NMSB should be accomplished on all LP compressor blades to part numbers FK23411,
FW23643, FW23741, FW23744, KH23403, KH23404 or LV11570 and is in two parts as follows:
(
a) Part 1 - Initial Inspection
[1] Do an inspection as defined in 1.D.(1) in accordance with the standard duty cycles.
For operators who conduct Non-Standard Operations (as defined in TLM Task
05-00-01), the cycles referred to in this NMSB are standard duty cycles. The
standard duty cycles consumed are calculated by multiplying the number of flights
flown by the applicable beta factors. Please refer to TLM Task 05-20-02 for the beta
factors.
In the absence of beta factors in the TLM, please contact Rolls-Royce through your
assigned Airline Support Team.
NOTE: For every ’missed approach/go-around’ or a ’Touch and Go’ performed,
additional standard duty cycles are to be added to the LP compressor
blade inspection interval cycle count, as defined in TLM Task 05-00-01.
NOTE: The additional standard duty cycles added for every ’missed
approach/go-around’ or a ’Touch and Go’ do not need to be multiplied by
the beta factor.
NOTE: Last inspections were in accordance with the Accomplishment Instructions
of NMSB 72-G702 or NMSB 72-G872 or NMSB 72-H311 or NMSB
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72-AH465 or EM Task 72-31-11 or AMM Task 72-31-41.
(
b) Part 2 - Repeat Inspection
[1] Re-inspect at an interval that does not exceed 1,200 cycles since last inspection in
accordance with this NMSB. For operators who conduct Non-Standard Operations
(as defined in TLM Task 05-00-01), the cycles referred to in this NMSB are standard
duty cycles. The standard duty cycles are calculated by multiplying the number of
flights flown by the applicable beta factors. Please refer to TLM Task 05-20-02 for
the beta factors.
In the absence of beta factors in the TLM, please contact Rolls-Royce through your
assigned Airline Support Team.
NOTE: For every ’missed approach/go-around’ or a ’Touch and Go’ performed,
additional standard duty cycles are to be added to the LP compressor
blade inspection interval cycle count, as defined in TLM Task 05-00-01.
NOTE: The additional standard duty cycles added for every ’missed
approach/go-around’ or a ’Touch and Go’ do not need to be multiplied by
the beta factor.
NOTE: Last inspections were in accordance with the Accomplishment Instructions
of NMSB 72-AL191.
E. Approval
NMSB 72-AL191 was approved by Rolls-Royce on May 30/2025. The technical content of this
document is approved under the authority of the DOA ref. EASA.21J.065.
F. Manpower
In service
(1) Time to remove LP compressor blades:
3 hours per LP compressor blade set (2 persons)
(2) Time to inspect LP compressor blades:
(
a) Ultrasonic phased array water-coupled inspection - 6 hours per LP compressor blade set
(1 person)
[1] The ultrasonic inspection defined in this procedure must be performed by personnel
certified to ultrasonic inspection Level 2 in accordance with EN4179/NAS410 or
alternative standards/guidelines accepted by the applicable National Aviation
Authority. All personnel utilising this technique must have received technique-specific
training either directly from the Rolls-Royce NDE Laboratory Derby or from
Rolls-Royce approved trainers.
[2] For inspections performed on behalf of Rolls-Royce, ultrasonic inspectors must be
certified to ultrasonic inspection Level 2 in accordance with EN4179/NAS410 and
hold a valid Rolls-Royce Authorisation Form for this technique.
[3] If an inspector has not performed one complete LP compressor blade set inspection
within three months, the inspector must watch the latest inspection video
(DV231567) prior to performing in-service inspections.
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[4] If an inspector has not performed one complete LP compressor blade set inspection
within six months, the inspector must watch the inspection video (DV231567) and be
re-assessed by a UT Level 3 who is familiar with the phased array inspection
technique, prior to performing in-service inspections. Re-assessment must be
performed using an LP compressor training blade that contains known EDM notches
(RRT116163 or RRT131971 as applicable). The inspector must follow the procedure
correctly and must successfully identify all known EDM notches without false calls.
[5] All personnel carrying out this inspection must watch the inspection video
(DV231567) and be re-assessed every twelve months by a UT Level 3 who is
familiar with the phased array inspection technique. Re-assessment must be
performed using an LP compressor training blade that contains known EDM notches
(RRT116163 or RRT131971 as applicable). The inspector must follow the procedure
correctly and must successfully identify all known EDM notches without false calls.
Record of annual re-assessment must be kept.
[6] If an Inspector has not performed one complete LP compressor blade set inspection
within twelve months, the inspector must receive specific training and approval either
directly by the Rolls-Royce NDE Laboratory Derby or from Rolls-Royce approved
trainers, prior to performing in-service inspections.
NOTE: For training refresher purposes the inspection video DV231567 is accessible at
the following location. Continue to use inspection video DV231567 for refresher
training purposes only until a new video is made available, which will include the
procedure detailed in this NMSB.
http://content.imageresourcemedia.com/preview/irstream/2/231567_Trent_700_
Ultrasonic_Phased_Array_Fan_Blade_Inspection.mp4?autoPlay=1
The video should be used for guidance only. The inspection must be carried out
as written in this NMSB.
(3) LP compressor blade re-lubrication
3 hours elapsed time (2 persons)
(4) Time to install LP compressor blades:
3 hours per LP compressor blade set (2 persons)
NOTE: A vibration ground run will be required.
In shop:
(1) Time to inspect LP compressor blades:
(
a) C-Scan inspection - 28 hours per LP compressor blade set (1 person)
NOTE: The C-scan ultrasonic inspection defined in 3.C. Accomplishment Instructions
shall only be performed by personnel who have received specific training either
directly by Rolls-Royce or from personnel trained by an approved Rolls-Royce
supplier. Training records are to be retained and kept up to date according to
both local and any Rolls-Royce policies.
G. Material Price and Availability
None.
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H. Tooling Price and Availability
(1) Tooling for LP compressor blade inspection:
Tool No. Description Qty
RRT115160 Phased array inspection kit
(water-coupled system)
1 off
NOTE: RRT115160 must be modified in accordance with Appendix 4 of this NMSB prior to
commencement of the inspection.
(2) Consumable Materials:
None.
(3) Tooling for refresher purposes:
Tool No. Description Qty
Ultrasonic Phased Array Water-coupled Inspection
RRT116163 EDM notched LP compressor
blade, used with RRT115161
Detail 1 index arm only
1 off
RRT131971 EDM notched LP compressor
blade, used with RRT131829
Detail 1 index arm
1 off
Please contact your assigned Rolls-Royce Airline Support Team for price and availability.
I. References
(1) Aircraft Maintenance Manual (AMM):
(
a) Task 72-31-41, Removal/Installation of LP Compressor Blades and Dampers
(b) Task 72-31-41, LP Compressor Rotor Blade - Re-apply the Dry Film Lubricant (FRSA031)
(c) Task 72-31-41, Water-Coupled Phased Array Ultrasonic Inspection of the LP Compressor
Blades (Removed From an Engine)
(d) Task 72-31-51, LP Compressor Disc - Re-apply the Dry Film Lubricant (FRSA017)
(2) Engine Manual (EM):
(a) Task 72-00-00, Special Procedures, Procedure to Rework LP Compressor Blade Convex
and Concave Aerofoil Surfaces following Water Coupled Phased Array Indication
(b) Task 72-31-11, C-Scan Inspection of the Low Pressure (LP) Compressor Blades for
Sub-Surface Cracks
(3) Overhaul Process (OP) Manual:
Task 70-00-00, Overhaul Process 237 - C-Scan General Requirements, Investigation of
Rejected Blades and Maintenance of Equipment
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(4) Rolls-Royce Non-Modification Service Bulletins:
(
a) 72-AH465
Engine - LP Compressor - Inspection of LP Compressor Blades - Non-Modification Service
Bulletin
(b) 72-G872
Engine - LP Compressor - Inspection of LP Compressor Blades - Non-Modification Service
Bulletin
(c) 72-H311
Engine - LP Compressor - Inspection of LP Compressor Blades - Non-Modification Service
Bulletin
(d) 72-G702
Engine - LP Compressor - Inspection of LP Compressor Blades - Non-Modification Service
Bulletin
(5) Time Limits Manual (TLM):
(a) Task 05-00-01, Recording and Control of the Lives of Parts
(b) Task 05-20-02, Group B Parts Mandatory Inspections
(6) Ultrasonic Phased Array Water-Coupled Inspection Video:
NOTE: For training refresher purposes the inspection video DV231567 accessible at the
following location can be used until new video becomes available. The video should be
used for guidance only. The instructions must be carried out as written in this NMSB.
DV231567
http://content.imageresourcemedia.com/preview/irstream/2/231567_Trent_700_
Ultrasonic_Phased_Array_Fan_Blade_Inspection.mp4?autoPlay=1
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2. Material Information
None.
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3. Accomplishment Instructions
A. Determine which method of inspection is to be undertaken as follows:
(1) For C-scan inspection of LP compressor blades in-shop use Section 3.C.
(2) For phased array inspection (water-coupled procedure) of LP compressor blades removed from
an engine on-wing or spare engine use Sections 3.B. and 3.D.
NOTE: If LP compressor blades are replaced in accordance with these inspections, a vibration
survey may be required before the engine returns to service. Refer to AMM Task
72-31-41, Removal/Installation for further details.
B. Accomplishment instructions for removal and installation of LP compressor blades from an engine
on-wing or spare engine for inspection in accordance with Section 3.D.
CAUTION: IN ORDER TO REDUCE THE POTENTIAL FOR MULTIPLE ENGINE IN-FLIGHT
SHUTDOWN, POWER LOSS OR OTHER ANOMALIES 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.
NOTE: Section 3.B. is only applicable if LP compressor blades are to be inspected in accordance
with Section 3.D.
(1) Remove LP compressor blades:
(
a) Remove the applicable LP compressor blades in accordance with AMM Task 72-31-41,
Removal/Installation.
(2) Accomplish ultrasonic inspection of LP compressor blades in accordance with Section 3.D.
(3) Re-apply the dry film lubricant to the LP compressor blade roots in accordance with AMM Task
72-31-41, Re-Lubrication of LP Compressor Blade Root Coatings - (FRSA031).
(4) Re-apply the dry film lubricant to the LP compressor disc in accordance with AMM Task
72-31-51, Re-apply the Dry Film Lubricant - (FRSA017).
(5) Install the LP compressor blades in accordance with AMM Task 72-31-41, Removal/Installation.
(6) Restore the engine to serviceable condition in accordance with AMM Task 72-31-41,
Removal/Installation.
(7) If replacement LP compressor blades have been installed, refer to AMM Task 72-31-41,
Removal/Installation to determine if a vibration survey is required.
C. Accomplishment instructions for C-scan inspection of LP compressor blades in-shop.
(1) C-scan inspect the LP compressor blades in accordance with EM Task 72-31-11.
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(2) If an LP compressor blade is rejected, inspection and blade data should be entered on the LP
compressor blade rejection proforma (Appendix 3) and returned to Rolls-Royce through your
assigned Airline Support Team with a copy of the archived scan data.
NOTE: If an LP compressor blade is rejected by the C-scan inspection, the cause of the
indication should be investigated in accordance with Overhaul Process 237, OP Task
70-00-00).
(3) Accomplishment of NMSB 72-AL191 must be recorded in Appendix 2 against the individual
blades.
D. Accomplishment instructions for phased array inspection (water-coupled procedure) of LP compressor
blades removed from an engine on-wing or spare engine.
(1) Inspect the LP compressor blades as follows:
(
a) Make sure that the water-coupled phased array kit (RRT115160) has a Rolls-Royce issued
certificate of functionality (post-modification) prior to inspection.
NOTE: The existing water-coupled phased array kit (RRT115160) is required to be
re-worked in accordance with Appendix 4. Please contact your assigned
Rolls-Royce Airline Support Team for further information on kit modifications.
(
b) Make sure that the personnel performing the inspection are certified, compliant to the
training requirements and adhere to the required number of inspections as detailed in
section 1.F.(2)(a) at the time of performing the inspection.
(c) Make sure that the OmniScan is calibrated either to the manufacturer’s specification or to a
relevant national standard or an approved supplier’s standard that is equivalent to a
relevant national standard.
(d) Inspect the LP compressor blades in accordance with Appendix 6.
(e) Locally save scan file data for every scan line completed (Appendix 6, Section E.) for a
period of 10 years.
(2) Accomplishment of NMSB 72-AL191 must be recorded in Appendix 9 against the individual
blades.
E. Accomplishment instructions for LP compressor blades rejected by phased array inspection in
accordance with Section 3.D.
NOTE: Common causes for LP compressor blade rejections by phased array inspection are
provided during training and details are included in the training video (DV231567, until new
video becomes available) and the Operation, Maintenance, Storage and Disposal Manual.
(1) LP compressor blades rejected from phased array inspection in accordance with Section 3.D.
should be clearly marked as reject. Mark the location of the rejection on the aerofoil surface.
(2) The rejected LP compressor blades should be sent to an overhaul facility for further investigation
in accordance with Special Procedure 15, EM Task 72-00-00.
(3) Details of rejected LP compressor blades must be recorded in accordance with Appendix 9 and
Appendix 10.
(4) Copies of all sheets from Appendix 9 and 10 must accompany the rejected LP compressor blade
to the overhaul facility.
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F. Data Management
(1) The scan files from the phased array inspections must be saved as detailed in Section 3.D.(e).
(2) All the scan files for the blades listed in Appendix 1 must be sent to or shared with Rolls-Royce
through your assigned Airline Support Team after completion of phased array inspection in
accordance with Section 3.D.
NOTE: The remaining scan files saved as a part of 3.D.(e) will be requested as required by
Rolls-Royce for further assessments and are required to be shared through your
assigned Airline Support Team.
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List of Appendices
Appendix Number Title Page Number Reference(s)
1 LP Compressor Blades subject to Inspection as defined
in Section 1.D.(1)
13 to 14
2 Ultrasonic Inspected Trent 700 LP Compressor Blade
Details
15 to 16
3 LP Compressor Blade C-Scan Rejection Proforma 17 to 18
4 Trent 700 LP Compressor Blade Inspection Kit
Modification Instructions
19 to 24
5 Trent 700 LP Compressor Blade Inspection Kit
Modification Completion Sheet
25 to 26
6 Trent 700 LP Compressor Blade Local Immersion
Ultrasonic Phased Array Inspection - Technical
Instruction
27 to 66
7 SETTINGS FOR
Master_T700_WaterCoupled_setup.ops: encoder
RRB−
668−105
67 to 68
8 SETTINGS FOR
Master_T700_WaterCoupled_setup.ops: encoder
RRB−
668−106
69 to 70
9 Trent 700 LP Compressor Blade Results Sheet −
Convex Sides Only
71 to 72
10 Trent 700 LP Compressor Blade Indication Sheet 73 to 74
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Appendix 1
LP Compressor Blades subject to Inspection as defined in Section 1.D.(1)
NOTE: The affected LP compressor blades listed in this Appendix are shown with the prefix RGF followed
by five unique numerical numbers only. Some LP compressor blades could have the prefix
RRWCFB in addition to the unique serial number listed in the table.
LP Compressor Blade Serial Numbers
RGF11969 RGF32364 RGF38277 RGF44703 RGF52868 RGF59446
RGF12063 RGF32596 RGF38307 RGF44841 RGF53073 RGF59540
RGF12273 RGF33125 RGF38329 RGF44912 RGF53713 RGF59672
RGF12333 RGF33364 RGF38793 RGF45142 RGF53726 RGF59769
RGF12356 RGF33533 RGF39292 RGF45218 RGF53888 RGF59816
RGF12396 RGF33759 RGF39419 RGF45442 RGF54344 RGF59963
RGF12489 RGF34367 RGF39436 RGF45542 RGF54444 RGF60016
RGF12581 RGF35117 RGF39533 RGF45572 RGF54458 RGF60692
RGF12583 RGF35157 RGF39835 RGF45597 RGF54548 RGF60952
RGF12627 RGF35163 RGF40139 RGF45876 RGF55353 RGF61051
RGF13466 RGF35577 RGF40254 RGF45877 RGF55681 RGF61135
RGF14827 RGF35652 RGF40530 RGF46149 RGF56100 RGF61271
RGF14864 RGF35673 RGF40583 RGF46327 RGF56198 RGF61487
RGF15037 RGF35688 RGF40709 RGF46513 RGF56271 RGF61566
RGF15099 RGF35752 RGF40907 RGF47082 RGF56278 RGF61937
RGF15108 RGF35773 RGF41010 RGF47117 RGF56650 RGF62218
RGF15587 RGF35833 RGF41289 RGF47199 RGF56930 RGF62231
RGF15800 RGF35942 RGF41710 RGF47635 RGF57029 RGF62622
RGF15840 RGF36066 RGF41744 RGF47928 RGF57396 RGF63453
RGF15874 RGF36068 RGF41816 RGF48025 RGF57410 RGF63752
RGF15930 RGF36137 RGF41830 RGF48192 RGF57414 RGF64371
RGF15965 RGF36450 RGF41961 RGF48764 RGF57473 RGF64673
RGF16512 RGF36845 RGF42039 RGF48841 RGF57695 RGF65039
RGF16741 RGF36904 RGF42191 RGF49076 RGF57872 RGF65441
RGF17145 RGF36929 RGF42425 RGF49960 RGF58179 RGF65677
RGF18165 RGF37104 RGF42475 RGF50011 RGF58265 RGF66288
RGF18705 RGF37211 RGF42595 RGF50025 RGF58448 RGF66337
RGF18834 RGF37272 RGF42634 RGF50537 RGF58466 RGF66572
RGF19045 RGF37522 RGF42722 RGF50550 RGF58547 RGF66606
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RGF19282 RGF37659 RGF43265 RGF50711 RGF58612 RGF67643
RGF20096 RGF37757 RGF43277 RGF51219 RGF58651 RGF68398
RGF20211 RGF37848 RGF43415 RGF51283 RGF58680 RGF68908
RGF20341 RGF37976 RGF43637 RGF51841 RGF58727 RGF70399
RGF21215 RGF38000 RGF43719 RGF51971 RGF58781 RGF70674
RGF21443 RGF38011 RGF44325 RGF52285 RGF58820
RGF22009 RGF38038 RGF44384 RGF52460 RGF58984
RGF23161 RGF38070 RGF44391 RGF52637 RGF59210
RGF24330 RGF38266 RGF44592 RGF52851 RGF59310
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Appendix 2
Ultrasonic Inspected Trent 700 LP Compressor Blade Details
Blade Position
Number
ESN Serial Number TSN CSN NMSB Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
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Appendix 3
LP Compressor Blade C-Scan Rejection Proforma
Results to be sent to Rolls-Royce as detailed in OP 237.
Blade Rejection Date:
Blade Part Number: Blade Serial Number:
Blade Time Since New (Hrs/Cycles):
Engine Serial Number: Module Serial Number:
Airline:
C-Scan Results:
1st Indication 2nd Indication 3rd Indication
Percentage of Height:
Weighting:
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Appendix 4
Trent 700 LP Compressor Blade Inspection Kit Modification Instructions
A. Scope
These instructions outline the steps to modify the Trent 700 LP compressor blade inspection kit
(RRT115160) to reduce the inspection zone coverage as required by NMSB 72-AL191 (replacing NMSB
72-AH465).
The modifications include the removal of the concave side inspection and the reduction of the convex side
inspection coverage.
The instructions detailed in this Appendix must be fully accomplished and the personnel performing the
modification must duly complete the modification completion sheet provided in Appendix 5.
Upon completion, the modification completion sheet must be submitted to Rolls-Royce for review along with
a photograph of the modified Scanning Frame. If deemed satisfactory, Rolls-Royce will issue a Certificate of
Functionality (CoF). The modified kit shall not be utilised for LP compressor blade inspections until the CoF
has been issued by Rolls-Royce.
B. Personnel Qualifications
Personnel performing the operations defined in this procedure must be certified to ultrasonic inspection
Level 2 in accordance with EN4179/NAS410 or alternative standards/guidelines accepted by the applicable
National Aviation Authority and must be familiar with the ultrasonic inspection procedure described in NMSB
72-AH465.
It is permissible for a Mechanic/Technician to provide additional assistance with the modification, if required.
C. Safety Precautions
It is the responsibility of the Operator/User to obtain detailed health and safety data for the materials in use
and to refer to local regulations to ensure safe working practice.
D. Tooling and Equipment
Tooling and equipment required for the modification will be provided, which includes index arm RRT131829
Detail 1 along with a Certificate of Conformity (CoC) and a new identity plate intended for attachment to the
scanning frame.
E. Modification of RRT115160 Inspection Kit
The modification of RRT115160 inspection kit includes:
• Removal of the concave scan rail (Appendix 4, Section E.(1))
• Change of the identity plate on the scanning frame (Appendix 4, Section E.(2))
• Replacement of the index arm RRT115161 (Detail 1) with the index arm RRT131829 (Detail 1)
(Appendix 4, Section E.(3))
• Retention of the index Arm RRT115161 (Detail 1) with the training blade (Appendix 4, Section E.(4))
• Disposal of the holder clamp (Appendix 4, Section E.(5))
• Completion of the modification completion sheet (Appendix 5).
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(1) Removal of the concave scan rail
(a) Disengage 5-off M3 hex-head bolts (illustrated in Figure 4.1) using an appropriate 2.5mm hex
key, to remove the entire concave scan rail with associated stopper and carriage from the
scanning frame.
(b) The removed carriage, stopper, bolts and concave scan rail should be disposed of or
recycled in compliance with local legislation and regulations.
(c) After the removal of concave scan rail, the modified scanning frame is depicted in Figure 4.2
for reference.
(2) Change of the identity plate on the scanning frame
(a) Disengage 2-off M3 bolts (illustrated in Figure 4.3) by using a 2mm hex Key to remove the
existing identity plate.
(b) Fasten the new identity plate utilising the removed 2-off M3 bolts, ensure they are tightly
secured. The new identity plate is supplied along with the index arm, RRT131829 (Detail 1).
(c) The old identity plate should be disposed or recycled in compliance with local legislation and
regulations.
(3) Replacement of the index arm RRT115161 (Detail 1) with the index arm RRT131829 (Detail 1)
(a) Replace RRT115161 (Detail 1) index arm with new index arm RRT131829 (Detail 1).
RRT131829 (Detail 1) is the new standard of the index arm to be used with the inspection
procedure, NMSB 72-AL191. It replaces RRT115161 (Detail 1) previously used with NMSB
72-AH465.
RRT131829 (Detail 1) introduces a reduced inspection area on the convex aerofoil of the LP
compressor blade. This reduction is accomplished by decreasing the number of indents on
the index arm. Specifically, RRT131829 (Detail 1) features 5 holes (resulting in 5 scan lines)
compared to the 9 holes (and 9 scan lines), refer to Figure 4.4.
RRT131829 (Detail 1) features a blue anodized finish on the probe holder, ensuring a clear
visual distinction from RRT115161 (Detail 1), refer to Figure 4.5.
(4) Retention of the index arm RRT115161 (Detail 1)
(a) RRT115161 (Detail 1) must not be discarded. It must be stored with the training blade
RRT116163 for training refresher purpose only.
NOTE: RRT131829 (Detail 1) is not compatible with the training blade RRT116163 hence
the requirement to store RRT115161 (Detail 1) with the training blade.
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def8001304
Removal of The Concave Scan Rail
Figure 4.1
Concave Scan Rail Removed 
Figure 4.2
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def8001305
Index Arm, Probe Holder Comparison 
Figure 4.5
Index Arm Comparison 
Figure 4.4
Identity Plate Replacement 
Figure 4.3
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(5) Disposal of the holder clamp
(a) The holder clamp refer to Figure 4.6, should be disposed or recycled in compliance with local
legislation and regulations.
The holder clamp, previously utilised to secure the LP compressor blade during inspection of
the concave aerofoil, is no longer required following the removal of the inspection to the
concave aerofoil.
(6) Kit modification completion and CoF
(a) The modification completion sheet in Appendix 5 shall be completed by the personnel
carrying out the modification and a copy of the completed sheet shall be stored along with the
inspection kit.
(b) A scanned copy of the completion sheet along with a photograph of the modified scanning
frame must be sent to Rolls-Royce electronically to the following e-mail address:
NDEToolingSupport@Rolls-Royce.com
This will enable Rolls-Royce to issue a CoF for the modified kit.
(c) The modified kit shall not be utilised for the LP compressor blade inspections until the CoF
has been issued by Rolls-Royce.
ALERT RB211−72−AL191
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def8001306
Holder Clamp 
Figure 4.6 
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Appendix 5
Trent 700 LP Compressor Blade Inspection Kit Modification Completion Sheet
Operator
Water-Coupled Kit S/N
Modified By (Name)
Modified By (Signature)
Date of Modification
Removal of the Concave Scan Rail Tick to confirm completion
Remove the entire Concave Scan Rail, along with its associated Stopper and
Carriage.
Change of Identity Plate Tick to confirm completion
Fasten the new ID plate to the Scanning Frame.
Replacing the RRT115161 (Detail 1) Index Arm Tick to confirm completion
Remove RRT115161 (Detail 1) Index Arm and replace it with RRT131829 (Detail
1) Index Arm
Retention of RRT115161 Index Arm (Detail 1) Tick to confirm completion
Store RRT115161 (Detail 1) Index Arm alongside Training Blade RRT116163
Disposal of Holder Clamp Tick to confirm completion
Dispose of Holder Clamp
Photograph of the Modified Inspection Kit Tick to confirm completion
Photograph of the modified scanning frame included
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Appendix 6
Trent 700 LP Compressor Blade Local Immersion Ultrasonic Phased Array Inspection - Technical Instruction
A. Tooling and Equipment
(1) The following equipment is required for this inspection:
Tool No. Description Qty
Olympus OmniScan MX2
(K23006894) or SX
(K23007084)
Phrased Array Ultrasonic Flaw
Detector
1 off
OmniScan External Charger 1 off
OmniScan Lithium Ion
Batteries
2 off
OMNI-A2-ADP20 OmniScan Encoder
Connector
1 off
RRT115160 Trent 700 Fan Blade Ultrasonic
Inspection Kit (Items listed in
Table 1)
1 off
(2) Trent 700 Fan Blade Ultrasonic Inspection Kit RRT115160 contains the parts that follow:
Table 1. List of items in kit RRT115160.
Tool No. Description Qty
ME64-LMP27 Sonaxis 64 Element 10MHz
Ultrasonic Array Probe
with 0.6mm Pitch
2 off
RRT115163 Probe Wedge 3 off
RRT115164 Water Housing 3 off
RRT115165 Probe Standoff 1 off
RRT076135 Fan Blade Holder 1 off
RRT131829 Fan blade scanning frame
arm assembly replacing
RRT115161
1 off
RRT115168 Fan Blade Holder Stand 1 off
RRT115166 Water Tray and Splash Guard with
two Non-slip Mats
1 off
RRT115167 Water Pump (Incorporated with
fixture, supply pipe and drain pipe)
2 off
RRT115162 Working Standard 1 off
RRB-668-105 or
RRB-668-106
Encoder Assembly (as
applicable*)
1 off
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Tool No. Description Qty
Male VGA to female VGA cable,
2M (for RRB-668-106 encoder
only)
1 off
Hex Keys (2.0mm, 2.5mm and
3mm AF)
1 off
Temporary Marker 2 off
Tape Measure (3 m) 1 off
Rule-Flexible (300mm) 1 off
SC HC 16GB microcards with
setup files
2 off
*Encoder assembly RRB-668-105 (Figure 6.1 left) is being phased out and will be replaced with an
alternative encoder standard RRB-668-106 (Figure 6.1 right) for new inspection kits and part
replacement orders (refer to RRT127355, OMSD RRT115160). Both encoder standards are
approved for inspection.
(3) The following consumable items are required:
Description
Tap Water or Demineralised Water
Paper Towels
(4) The equipment associated with this inspection to be used for practice and training refresher, and
held by the operator is listed below:
(a) RRT116163 - Training fan blade used in conjunction with RRT115161 (Detail 1) index arm
only.
(b) RRT131971 - Training fan blade replacing RRT116163 for use with RRT131829 (Detail 1)
index arm.
Both training blade standards are approved for use.
NOTE: The OmniScan must be calibrated annually either to the manufacturer’s specification or to
a relevant national standard or an approved supplier’s standard that is equivalent to a
relevant national standard.
(5) Refer OMSD RRT115160 for details on the general operation, maintenance, storage and disposal
of the Trent 700 Local Immersion Ultrasonic Phased Array Fan Blade Inspection Kit (RRT115160)
B. Inspection Setup and Preparation
CAUTION: PRIOR TO INSPECTION, VISUALLY CHECK ALL EQUIPMENT FOR SIGNS OF WEAR, DAMAGE
OR CORROSION AND ENSURE MECHANICAL PARTS OF INSPECTION HARDWARE ARE
FUNCTIONING AS REQUIRED. DO NOT USE DAMAGED OR MALFUNCTIONING PARTS OF
INSPECTION HARDWARE. REPORT THESE TO SUPERVISION TO BE SENT FOR REPAIR OR
REPLACED.
(1) Place the tray on a level bench with a non-slip top.
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(2) Assemble the fan blade holder stand with the fan blade holder (Appendix 6.1). Place the two
non-slip mats into the tray - one at each end. Place the stand/holder into the tray on top of the
mats.
(3) Fill the water tray with clean water to minimum level of 50 mm (2.0 in.) depth.
(4) Make sure that the filter of the water pump is not blocked. A blocked filter will slow down the water
flow and could damage the pump. To unblock the holes in the filter: detach the filter using the
screw on the side of the filter and wash it in clean water.
(5) Fix the pump to the edge of the tray so it is completely submerged and connect the pipes to the
pump as shown in Figure 6.2.
(6) Check the working standard cavity seal does not leak water:
(a) Submerge the working standard into the tray of water (Figure 6.3) for 3 minutes.
(b) After 3 minutes remove the working standard from water and wipe the surface dry.
(c) Check for presence of water in the cavity.
If water is present inside the cavity - the working standard must not be used, a replacement
shall be requested and the broken standard must be sent for repair.
If no water is visible inside the cavity - return the working standard into the tray of water.
(7) Check the probe wedge. Check that the feet do not exhibit significant wear and the indication poles
are free to move up and down. If either of the two front feet are less than 15mm in height or the
rear foot is less than 5mm in height replace the wedge. Figure 6.4 shows how to measure the
height of the front and rear feet.
(8) Connect the probe to the OmniScan using the OmniScan connector, as shown in Figure 6.5.
Ensure the connector is screwed into the OmniScan tightly.
(9) Ensure the Secure Digital High Capacity (SDHC) memory card is in the OmniScan memory card
slot and there is sufficient memory available to save the files from the planned inspections.
NOTE: If the switch on the side of the memory card is set to Lock, the OmniScan will not boot up
correctly.
(10) Turn on the OmniScan by pressing the Power Button for one second. Select software version MXU
4.4 if not selected automatically.
(11) Ensure the OmniScan is charging or the battery has sufficient charge for the required inspection.
(12) Load the T700_WaterCoupled_setup.ops file.
Press File→Setup→Open
Select T700_WaterCoupled_setup.ops
Press Open.
(13) Check that the OmniScan settings are correct. To do this press File →Report→Preview then check
the setting match those given in Appendix 7 for encoder RRB-668-105, and Appendix 8 for encoder
RRB-668-106.
NOTE: For encoder replacement from RRB-668-105 to RRB-668-106, refer to OMSD
RRT115160.
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(14) Ensure that the A-Scan will display the maximum signal.
Press Display.
Select Highest (%) Data Source.
NOTE: If a window appears saying: ’This will erase the current data. Do you want to continue?’.
Select Yes.
NOTE: If at any point the OmniScan pop-up message says: ’The set-up has been modified.
Would you like to save the setup. Select ’No’ by pressing the Cancel key.
If the setup is accidentally saved, load the Master_T700_WaterCoupled_setup.ops. Check the
settings are the same as in Appendix 7 (or Appendix 8 as applicable). Save this setup as
T700_WaterCoupled_setup.ops.
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ROTOE
RRB-668-105  RRB-668-106
Two alternative encoder standards: RRB-668-105 (left) and RRB-668-106 (right)
Figure 6.1
Tray filled with
water to a depth
of 50mm
Probe supply pipe
Flow control tap.  Probe supply tap.  Pump.
Adjustable to regulate flow  Fully open during use.  Attached to right-edge of the tray. Located
rate to probe.  under the water, at the front-right of the tray.
Suction
cups
Water out
Water in
Water circulation system
Figure 6.2
def8001307
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def8001308
Placement of working standard in tray of water 
Figure 6.3
Image showing how to measure probe wedge front feet (left) and the rear foot (right) 
Figure 6.4 
Attaching the probe to the OmniScan (MX2 pictured) 
Figure 6.5
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C. Dead Element Check and Element Normalisation
The dead element check and element normalisation must be performed:
• before inspecting fan blade components;
• and if the array probe, wedge or working standard has been replaced.
The element normalisation check must be performed as part of the post-inspection (Appendix 6, Section F. -
Post Inspection Procedure).
(1) Attach the probe to the STAND OFF using the 4 screws as shown in Figure 6.6.
(2) Place the probe STAND OFF on the working standard so that it locates on the end of the working
standard as shown in Figure 6.6. Ensure the STAND OFF sits flat on the surface of the working
standard so a flat straight line from the front wall appears across all elements of the array in the
S-scan as shown in Figure 6.8. If this is not the case, check the attachment of the probe to the
probe STAND OFF.
(a) Dead Element check
[
1] Set the aperture to 1 element.
Press Focal Law→Aperture.
Select Element Qty.=1, First Element=1, Last Element=64, Element Step=1.0.
Press Accept Key (Figure 6.7(a)).
[2] Check the S-scan display for the presence of dead elements. A dead element will show
as a line of zero signal as shown in Figure 6.8. If adjacent elements appear dead check
that the probe is connected correctly with the OmniScan and both screws are tight.
[3] If any dead elements are still present, the probe must not be used for the inspection
and shall be replaced. The broken array probe must be sent for repair.
[4] Return the aperture size to original setting (8 elements)
Press Focal Law→ Aperture.
Select Element Qty. = 8.
Press Accept Key (Figure 6.7(a)).
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def8001309
Array and Probe STAND OFF placement on the working standard required for dead element check and 
element normalisation 
Figure 6.6
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ROTOI
Display touch  Alarm indicator
lights
Accept key  (See view (a))
ComniS
Scroll
knob
Play key.
Cancel key  (See view (b))
Freeze key
Data Selector
key
Gain key
OLYMPUS
Help key  Power key
(a) Accept key  (b) Cancel key
Accept and Cancel keys
Figure 6.7
Dead element
=
120
Screenshot showing dead element
Figure 6.8
def8001310
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(b) Element Normalisation
[
1] Press Wizard →Calibration.
Select Ultrasound in Type.
Select Sensitivity in Mode.
Press Apply to All VPA.
Press Start in Select Calibration tab.
[2] Press Clear Calib.
Press Yes to confirm ‘to lose the sensitivity calibration’.
Set 80% Ref. Amplitude.
Set 5.0% Tolerance.
Press Next.
[3] Set Last VPA as 57.
Press Next.
[4] Adjust Gate A to position the gate over the right-most echo in the A-Scan, Figure 6.9.
Select Start: 23.5mm.
Select Width: 3mm.
Threshold: 60%.
Press Next.
[5] Adjust the gain so that responses from all 57 apertures (Figure 6.9, bottom window) are
located between 10% and 100%.
NOTE: The gain setting should be approximately 20dB.
Press Next.
[
6] Press Calibrate.
[7] Ensure all aperture responses are within the 5% tolerance bars, as shown in Figure
6.10. If the signals are not within the tolerance bars, check for trapped air under the
probe. Remove air by tilting the probe from side to side. Repeat previous steps.
If it is still not possible to normalise the elements then the probe must not be used for
the inspection and shall be replaced. The broken array probe must be sent for repair.
[8] Press Accept.
[9] Return Gate A to original position.
Select Gates/Alarms.
Select A in Gate, Position in Parameters, True Depth in Geometry.
Set 4.2mm in Start and 20mm in Width.
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Set 60% in Threshold.
NOTE: If the normalisation procedure cannot be performed successfully, clear any
existing settings by pressing the
‘Clear Calib’ button within the calibration
wizard. Observe the bottom left of the OmniScan display, a green ‘S’ indicated
a sensitivity calibration has been applied and a yellow ‘S’ indicates the
calibration has been cleared as shown in Figure 6.11.
[10] Record the gain for normalisation on the results sheet in Appendix 9.
[11] Detach the probe from the STAND OFF to be ready for next step.
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def8001311
Typical response from the elements post−normalisation
Figure 6.10
Typical response from the elements pre−normalisation
Figure 6.9
A green ’S’ at the bottom left of the OmniScan display indicates a sensitivity calibration has been
applied and a yellow ’S’ indicates the calibration has been cleared
Figure 6.11
ALERT RB211−72−AL191
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D. Probe Calibration
The probe calibration must be performed:
• before inspecting fan blade components;
• if the array probe, wedge or working standard has been replaced;
• upon the completion of inspection (Appendix 6, Section F. - Post Inspection Procedure).
The same working standard must be used all the time.
(1) To perform the calibration procedure
The sensitivity of the probe is set using the 0.50mm long by 0.25mm deep notch positioned in the
working standard at the material depth of 6mm.
(a) Check Gate A is at the original position. Start at 4.2mm and Width of 20mm.
(b) Attach the probe to the wedge in the correct orientation using the four screws as shown in
Figure 6.12.
(c) Position the probe/wedge over the notch located at 6mm depth. Use the pole indicators and
ensure all three feet of the wedge are in firm contact with the working standard surface and
maximise the signal from the notch (Figure 6.13).
Ensure the signal from the notch is located in the middle of S-scan as shown in Figure 6.13.
Observe the signal in the S-scan caused by the step between the 6mm slot and the 5mm slot.
Ensure the probe orientation is correct by making the step signal horizontal in the S-scan
(Figure 6.13).
ALERT RB211−72−AL191
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def8001312
Correct probe−wedge orientation
Figure 6.12
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ROTOE
6mm deep
notch
6mm slot
Step  5mm slot
Front
Notch
MIDDLE (VPA 29)
Notch signal:
maximised and
positioned at middle
of 5-Scan, VPA 29
Step signal: horizontal
Array and wedge placement on the working standard required for calibration
Figure 6.13
def8001313
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### Page 46

(d) Adjust the gain setting to set the maximised signal to 100% full screen height.
(e) Then increase the gain by additional 6dB.
(f) Press the Accept key (Figure 6.7(a)) to set the gain.
(g) Scan the probe over all six notches. Ensure all notches give a signal of at least 200% full
screen height. If any of the notches give a signal of less than this - repeat the probe
calibration (Appendix 6, Section D.).
NOTE: Ensure the middle of the probe is used so that the signal from each of the six
notches is in the middle of the S-scan as shown in Figure 6.13.
Observe also the response from all the steps. Ensure the response from each step is
consistent across the S-scan.
NOTE: For certain slot thicknesses, the notch response and step response may occur
together within the gate. Ensure the A% reading is referring only to the notch
response. If necessary, Gate A width can be reduced from 20mm (default value) to
11.5mm for the purposes of Step (g). Gate A width must be returned to 20mm upon
completion of Step (g).
Figure 6.14 shows the signal from the notch at 6mm depth and from the 6mm-to-5mm step
after calibration.
(h) Apply a correction factor by adjusting the gain setting as directed by the engraved instructions
on the working standard in use. For example, if the gain is 27dB following Steps (d) thru (g),
and the engraving on the working standard says ’SUBTRACT 3dB’, then the gain setting after
the application of the correction factor is 24dB.
NOTE: The gain setting after step (h) should be expected to be approximately 24dB.
(i) The calibration gain settings must be recorded on the results sheet in Appendix 9.
(j) Enable audible output for the alarm:
Press File→Gates/Alarms.
Press Output.
Set Alarm: Output 1.
Set Count: Count 1.
Set Sound: ON.
Set Delay: 0.
Set Hold Time: 1000 ms.
(k) Activate the visual and audible alarms:
Press File→Gates/Alarms.
Press Alarm.
Set Alarm: Alarm 1.
Set Condition: Gate A.
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Set Operator: And.
Set Count: None.
Set State: On.
(l) Place the probe on the working standard and make sure the alarm is activated when the
probe is moved over the notches and the notch signals appear in gate: a red light on the
instrument panel and a sound signal will indicate that the alarm is activated.
(m) Once completed, remove the working standard from water and wipe it dry.
NOTE: If the ultrasonic array probe cannot be calibrated as per Appendix 6, Section D.,
replace the ultrasonic array probe and contact your assigned Rolls-Royce Airline
Support Team.
ALERT RB211−72−AL191
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### Page 48

def8001314
S−Scan showing response from the 6mm deep notch (left) and from the 6mm−to−5mm step (right) after
calibration − Figure 6.14
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### Page 49

E. Inspection Procedure
(1) All blades are inspected on the convex side of the aerofoil only.
(a) LP compressor blades are required to be appropriately organised prior and during inspection
to ensure every fan blade is inspected and tracked.
[
1] Use suitable fixtures or racks to store the LP compressor blades during the inspection
(or)
[2] Lay the LP compressor blades out on inspection tables or a suitable surface.
[3] Follow a sequential order while inspecting the blades.
(b) Ensure the ultrasonic probe has been correctly setup and prepared per Appendix 6, Section
B. and Appendix 7 (or Appendix 8 as applicable).
(c) Ensure the dead element check and element normalisation have been performed per
Appendix 6, Section C.
(d) Ensure sensitivity calibration has been performed per Appendix 6, Section D.
(e) Make sure Gate A is at the original position: Start at 4.2mm and Width of 20mm.
(f) Connect the encoder to the OmniScan using the scanner interface.
(g) Set the correct polarity of the encoder as follows:
Press Scan → Encoder → Polarity.
Select Inverse.
(h) Attach the probe/wedge to the probe holder on the index arm (refer to Figure 6.15):
[1] Remove the end attachment from the probe holder by pressing the release button on
the end attachment.
[2] Attach the probe/wedge to the probe holder using the two hex screws in the probe
holder. Ensure the orientation is as shown in Figure 6.15.
[3] Place the probe cable inside of the probe holder.
[4] Replace the end attachment to the probe holder.
(i) Place the first fan blade into the fan blade holder, convex side up.
(j) Attach the scanning frame to the blade as shown in Figure 6.16 and Figure 6.17:
[1] Ensure the fan blade surface is clean and is free of any loose dust, dirt or grease.
[2] Make sure the scanning frame is attached to the leading edge of the blade.
[3] Position the scanning frame on the blade so that the axial locating rod is touching the
holder support, as shown in Figure 6.17.
[4] It is possible for the tip of the axial locating rod to wear down over time. Check the
length of the axial locating rod is between 80 and 90mm.
[5] Align the root-end and tip-end clamps so the blocks are against the leading-edge of the
fan blade, as shown in Figure 6.18.
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ROTOE
[6] Squeeze the clamps shut. Ensure the blocks are still against the leading-edge as
shown in Figure 6.18.
17] To release the clamps, squeeze the handle with the middle lever, Figure 6.19.
Probe holder
End attachment
Index arm
Probe holder
End attachment
removed, showing the
release button circled
Hex screw
Step h [1]
Pro be/wed ge
attached to probe
holder (note the
correct orientation)
Step h [2]
Probe cable inside
probe holder  Pipe attachment hole
End attachment
replaced
Step h [3] and h [4]
Correct attachment of probe/wedge to probe attachment on index arm
Figure 6.15
L  def8001315
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def8001326
Correct axial position of the scanning frame during inspection
Figure 6.17
Fan blade suction (convex) side up on the holder
Figure 6.16
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def8001327
Squeeze the middle lever to release the clamps
Figure 6.19
Correct position of the clamps on the fan blade for the root−end (left)
and the tip−end (right)
Figure 6.18
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(k) Place the index arm/holder into the carriage. Ensure the two carriage pins are closed so that
the index arm holder is secure to the carriage, as shown in Figure 6.20. Note the index
selector pin is positioned away from the blade, facing the user end of the index arm.
(l) Ensure the
‘Convex’ label on the index arm is facing upward, as shown in Figure 6.21.
(m) Pull the water supply pipe through the pipe clip on the index arm, the pipe attachment hole on
probe holder, and connect it to the probe wedge (Figure 6.22).
(n) Adjust the position and orientation of the pipe clip on the index arm to ensure the pipe does
not interfere with the scanning motion (Figure 6.22). The pipe clip can be also used to secure
the probe cable.
(o) Make sure the string encoder clip is connected to the carriage, as shown in Figure 6.23.
(p) Set the index arm to the first index position and ensure the Index hole selector pin has
dropped firmly into the first index hole as shown in Figure 6.24.
(q) Place the probe into the water housing as shown in Figure 6.25.
(r) Turn on the water pump and leave running for 5 minutes before starting the scan. Meanwhile,
check the water housing can maintain a seal against the blade by applying pressure to the
base of the water housing.
(s) Move the index arm to the scan start position, and zero the encoder by pressing Set to Origin.
(t) Apply pressure to the probe handle using the right hand to ensure the three feet of the wedge
are always in contact with the blade surface. Use the indication poles to help check that the 2
front feet are in firm contact with the blade (Figure 6.26).
Apply pressure also to the compression disc of the water housing using the left hand to form
a seal and enable the water housing to fill with water and couple the ultrasound to the blade.
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def8001316
Water supply pipe attached to the pipe clip on the index arm (left), and to the probe/wedge assembly (right). 
Figure 6.22
Orientation of the index arm for inspection: ’Convex’ label upwards
Figure 6.21
Image showing the correct orientation of the index arm holder
Figure 6.20
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def8001317
Index arm set to the first index hole and at the scan start position
Figure 6.24
String encoder connected to the carriage for the inspection
Figure 6.23
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def8001318
Probe placed into water housing
Figure 6.25
Indication poles when front feet are correctly seated on the blade (left) and when not correctly seated on
the blade (right)
Figure 6.26
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(u) Allow the signal in the S-scan display to settle and stabilise. Figure 6.27 shows example
S-scan displays which have not stabilised.
The reflected signal from the blade top surface (
‘blade surface signal’) needs to be visible
across the entire S-scan display and it must be made to be as flat/ horizontal as possible by
ensuring all 3 feet of the wedge are in contact with the blade surface. A typical S-scan is
shown in Figure 6.28.
NOTE: Sometimes due to surface curvature, the blade surface signal may not always
appear perfectly horizontal.
(v) At every position on the blade scan, the blade surface signal should lie entirely within the
Interface gate as shown in Figure 6.28. If this is not achieved, check all three feet of the
probe wedge are in contact with the fan blade surface.
(w) Remove any air bubbles under the probe by lifting the probe up and down and rocking it side
to side. All air bubbles must be removed before starting to scan the probe.
(x) Using both hands slowly scan the probe and water housing along the blade. The scanning
direction is from right to left, scanning from the tip to the root of the blade.
The probe should be scanned slowly and carefully to maintain correct probe seating on the
blade. All three feet of the wedge must remain in contact. If the back foot separates from the
blade surface, this is apparent in the C-scan image.
Figure 6.29 shows example C-scan images when the back foot separates from the surface.
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def8001319
Example of the same S−Scan display at different times showing moving air bubbles before it has settled 
Figure 6.27
Screenshot of the OmniScan showing the front wall signal
Figure 6.28
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def8001320
C−Scan images showing response caused by varying degrees of rear foot lift−off (top and middle).
A C−Scan showing when the wedge is correctly seated is included for comparison (bottom).
Figure 6.29
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(y) If the water level is not maintained to a sufficient level the blade surface signal will not be
visible in the S-scan and white lines will appear in the C-scan as shown in Figure 6.30. If this
occurs, consider increasing the water flow rate and tilting the blade to reduce the water loss.
Scan lines with the white regions in C-scan indicating the lack of coupling must be
re-scanned.
(z) If the scan speed exceeds 90mm/s, black lines will appear in the C-scan showing lines of
data that were not recorded, as shown in Figure 6.31. If this occurs, re-scan.
(aa) The finish point of the scan is when the carriage reaches the end of the rail, as shown in
Figure 6.32.
(ab) Once a scan line is finished - freeze the scan by pressing the Freeze/Pause key on the
Omniscan.
View the C-scan for potential defect indications.
(ac) The defect indications can be identified as isolated regions of high-amplitude signal standing
out from the surface signal background, as shown in Figure 6.33(b). They can be located
anywhere within the scan area, as shown in Figure 6.33(c).
NOTE: To improve visualisation, the C-scan display can be made to fill the entire display
screen by changing the display option from A-C-S to C (indicated below). The
display option must be returned to A-C-S before continuing to the next scan line.
Refer to Figure 6.34.
(ad) Zoom in on potential indication and measure the maximum signal height by moving the data
selector lines (the vertical and horizontal lines on the C-scan) over the indication, as shown in
Figure 6.35. This can be done by double tapping the touch-screen display on the C-scan.
NOTE: To zoom out - double tap on numerical scale at the bottom of the screen to return to
the full scan display.
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