Airworthiness Directive Schedule Engines Rolls Royce 250 Series Turbine CEB 48 Al250
User Manual: CEB-48
Open the PDF directly: View PDF .
Page Count: 26
- DCA/AL250/1 Cancelled: Information now in Maintenance Manual
- DCA/AL250/2 Cancelled: Once only inspection, purpose fulfilled
- DCA/AL250/3 External Oil Sump Screen - Removal
- DCA/AL250/4 Gasifier Turbine Oil Sump Screen - Removal
- DCA/AL250/5 Cancelled - Information now in Maintenance Manual
- DCA/AL250/6 Sixth Stage Compressor Blades - Modification
- DCA/AL250/7 Compressor Rotor, Second and Third Stage Wheel Assembly - Rework
- DCA/AL250/8 Compressor Case Assembly Vanes Leading Edge - Rework
- DCA/AL250/9 Compound Governor For PY Venting System - Modification
- DCA/AL250/10 Fuel Control Start Derichment Bellows - Modification
- DCA/AL250/11 Cancelled: Once only inspection, purpose fulfilled
- DCA/AL250/12 Accessories Gear Box - Modification
- DCA/AL250/13 Compressor Wheels Stages 1-6 - Glass Bead Peen - Modification
- DCA/AL250/14 Compressor PC Filter Insert - Inspection
- DCA/AL250/15 Compressor PC Filter Insert - Rework and Modification
- DCA/AL250/16 Cancelled: DCA/AL250/19A refers
- DCA/AL250/17 Power Turbine Governor to Control Fuel Tube - Modification
- DCA/AL250/18 Fuel Control Rigging - Inspection
- DCA/AL250/19A Critical Components - Life Limitations
- DCA/AL250/20 Compressor Bleed Valve - Modification
- DCA/AL250/21B Power Turbine Outer Coupling Nut - Inspection
- DCA/AL250/22C Turbine Wheel - Inspection, Retirement and Operating Limitation
- DCA/AL250/23 Fuel Pump LP Filter Element - Replacement Fuel Pump HP Filter Assembly - Installation
- DCA/AL250/24 Fuel Pump Drive - Inspection
- DCA/AL250/25 Compressor Wheels - Retirement
- DCA/AL250/26A Turbine Wheels - Removal
- DCA/AL250/27 N2 (Electronic) Overspeed Control System - Deactivation
- DCA/AL250/28 HP Fuel Control Filter - Modification
- DCA/AL250/29A Engine Fuel and Control System – Inspection
- DCA/AL250/30 Turbine Assembly, Splined Adaptor Locknut - Inspection
- DCA/AL250/31 Turbine Assembly - Modification
- DCA/AL250/32A Gas Producer Oil Tube - Modification
- DCA/AL250/33 Fuel Control - Removal
- DCA/AL250/34 Second Stage turbine Nozzle - Modification
- DCA/AL250/35 Scavenge Line Air/Oil Separator Assembly - Installation
- DCA/AL250/36B Unapproved Components - Removal
- DCA/AL250/37 Superior Air Parts Bearings - Inspection
- DCA/AL250/38A Electrical Harness, HMU and ECU - Replacement
- DCA/AL250/39 Fuel Control Bellows - Replacement
- DCA/AL250/40A Torquemeter - Replacement
- DCA/AL250/41 Third Stage Turbine – Life Limitation
- DCA/AL250/42 Cancel DCA/AL250/43 refers
- DCA/AL250/43 Cancelled - DCA/AL250/50 refers
- DCA/AL250/44 Power lever Angle Potentiometer - Inspection
- DCA/AL250/45 C28 3rd Stage Turbine Wheels – Life Limitation
- DCA/AL250/46B Compressor Couplings – Removal from Service
- DCA/AL250/47 Turbine Wheel Energy Absorbing Ring - Installation
- DCA/AL250/48 Third Stage Turbine Wheels – Inspection
- DCA/AL250/49 Gas Producer Rotor Assembly Tie Bolts - Replacement
- DCA/AL250/50 Fuel Nozzle Screen – Inspection
- DCA/AL250/51A Third and Fourth Stage Turbine Wheels – Speed Range Life Limitation
- DCA/AL250/52 Generator Idler Gearshaft – Life Limit
- DCA/AL250/53 4th Stage Turbine Nozzles – Life Limit
- DCA/AL250/54 Turbine & Compressor Assemblies – Inspection
- DCA/AL250/55 Outer Combustion Case Assembly – Inspection
- DCA/AL250/56 Compressor Mount Assembly – Inspection
- DCA/AL250/57 Cancelled – FAA AD 2015-02-22 refers
- From 1 October 2012 the Civil Aviation Authority of New Zealand (CAA) will no longer rewrite the text of State of Design ADs. Applicable State of Design ADs will be listed below and you can obtain them directly from the National Airworthiness Authority (NAA) web sites. Links to the NAA web sites are available on the CAA web site athttp://www.caa.govt.nz/airworthiness-directives/states-of-design/If additional NZ ADs need to be issued when an unsafe condition is found to exist in an aircraft or aeronautical product in NZ, they will be added to the list below.
- * 2015-02-22 Cancelled – FAA AD 2017-18-14 refers
- DCA/AL250/58 No. 5 Engine Bearing with P/N M250-10106 – Replacement
- * 2017-18-14 3rd and 4th Stage Turbine Wheels – Inspection
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Issued 22 February 2018 Page 1 of 26 CAA of NZ
Airworthiness Directive Schedule
Engines
Rolls-Royce 250 Series Turbine Engines
22 February 2018
Notes: 1. This AD schedule is applicable to Rolls-Royce Corporation 250 series engines
(formerly Allison Engine Company, Allison Gas Turbine Division and Detroit Diesel
Allison) manufactured under FAA Type Certificate Numbers:
Engine Series:
FAA Type Certificate Number:
250-B17B
E10CE
250-B17C
E10CE
250-C18
E4CE
250-C18A
E4CE
250-C18C
E4CE
250-C20
E4CE
250-C20B
E4CE
250-C20F
E4CE
250-C20J
E4CE
250-C20R/2
E4CE
250-C28
E1GL
250-C30
E1GL
250-C30M
E1GL
250-C30P
E1GL
250-C30S
E1GL
250-C47B
E1GL
250-C47B/8
E1GL
250-C47E/4
E1GL
250-C47M
E1GL
2. The Federal Aviation Administration (FAA) is the National Airworthiness Authority
(NAA) responsible for the issue of State of Design Airworthiness Directives (ADs) for
Rolls-Royce Corporation 250 series engines. State of Design ADs can be obtained
directly from the FAA web site at
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/MainFrame?OpenFra
meSet
3. The date above indicates the amendment date of this schedule.
4. New or amended ADs are shown with an asterisk *
Contents
DCA/AL250/1 Cancelled: Information now in Maintenance Manual ........................................................ 3
DCA/AL250/2 Cancelled: Once only inspection, purpose fulfilled ........................................................... 3
DCA/AL250/3 External Oil Sump Screen - Removal ............................................................................... 3
DCA/AL250/4 Gasifier Turbine Oil Sump Screen - Removal ................................................................... 3
DCA/AL250/5 Cancelled - Information now in Maintenance Manual ....................................................... 3
DCA/AL250/6 Sixth Stage Compressor Blades - Modification ................................................................. 3
DCA/AL250/7 Compressor Rotor, Second and Third Stage Wheel Assembly - Rework ......................... 3
DCA/AL250/8 Compressor Case Assembly Vanes Leading Edge - Rework ........................................... 3
DCA/AL250/9 Compound Governor For PY Venting System - Modification ............................................ 3
DCA/AL250/10 Fuel Control Start Derichment Bellows - Modification ....................................................... 4
DCA/AL250/11 Cancelled: Once only inspection, purpose fulfilled ........................................................... 4
DCA/AL250/12 Accessories Gear Box - Modification ................................................................................ 4
DCA/AL250/13 Compressor Wheels Stages 1-6 - Glass Bead Peen - Modification ................................. 4
DCA/AL250/14 Compressor PC Filter Insert - Inspection .......................................................................... 4
DCA/AL250/15 Compressor PC Filter Insert - Rework and Modification ................................................... 4
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Issued 22 February 2018 Page 2 of 26 CAA of NZ
DCA/AL250/16 Cancelled: DCA/AL250/19A refers ................................................................................... 4
DCA/AL250/17 Power Turbine Governor to Control Fuel Tube - Modification ........................................... 4
DCA/AL250/18 Fuel Control Rigging - Inspection...................................................................................... 5
DCA/AL250/19A Critical Components - Life Limitations .............................................................................. 5
DCA/AL250/20 Compressor Bleed Valve - Modification ............................................................................ 5
DCA/AL250/21B Power Turbine Outer Coupling Nut - Inspection ............................................................... 5
DCA/AL250/22C Turbine Wheel - Inspection, Retirement and Operating Limitation ................................... 6
DCA/AL250/23 Fuel Pump LP Filter Element - Replacement Fuel Pump HP Filter Assembly -
Installation ......................................................................................................................... 6
DCA/AL250/24 Fuel Pump Drive - Inspection ............................................................................................ 7
DCA/AL250/25 Compressor Wheels - Retirement .................................................................................... 7
DCA/AL250/26A Turbine Wheels - Removal ............................................................................................... 7
DCA/AL250/27 N2 (Electronic) Overspeed Control System - Deactivation ............................................... 8
DCA/AL250/28 HP Fuel Control Filter - Modification ................................................................................. 8
DCA/AL250/29A Engine Fuel and Control System – Inspection .................................................................. 8
DCA/AL250/30 Turbine Assembly, Splined Adaptor Locknut - Inspection ................................................ 9
DCA/AL250/31 Turbine Assembly - Modification ....................................................................................... 9
DCA/AL250/32A Gas Producer Oil Tube - Modification ............................................................................... 9
DCA/AL250/33 Fuel Control - Removal ..................................................................................................... 9
DCA/AL250/34 Second Stage turbine Nozzle - Modification ................................................................... 10
DCA/AL250/35 Scavenge Line Air/Oil Separator Assembly - Installation ................................................ 10
DCA/AL250/36B Unapproved Components - Removal .............................................................................. 10
DCA/AL250/37 Superior Air Parts Bearings - Inspection ......................................................................... 11
DCA/AL250/38A Electrical Harness, HMU and ECU - Replacement ......................................................... 12
DCA/AL250/39 Fuel Control Bellows - Replacement ............................................................................... 12
DCA/AL250/40A Torquemeter - Replacement ........................................................................................... 13
DCA/AL250/41 Third Stage Turbine – Life Limitation .............................................................................. 13
DCA/AL250/42 Cancel DCA/AL250/43 refers .......................................................................................... 14
DCA/AL250/43 Cancelled - DCA/AL250/50 refers ................................................................................... 14
DCA/AL250/44 Power lever Angle Potentiometer - Inspection ................................................................ 14
DCA/AL250/45 C28 3rd Stage Turbine Wheels – Life Limitation ............................................................. 15
DCA/AL250/46B Compressor Couplings – Removal from Service ............................................................ 16
DCA/AL250/47 Turbine Wheel Energy Absorbing Ring - Installation ...................................................... 17
DCA/AL250/48 Third Stage Turbine Wheels – Inspection ....................................................................... 18
DCA/AL250/49 Gas Producer Rotor Assembly Tie Bolts - Replacement ................................................ 18
DCA/AL250/50 Fuel Nozzle Screen – Inspection .................................................................................... 19
DCA/AL250/51A Third and Fourth Stage Turbine Wheels – Speed Range Life Limitation ....................... 20
DCA/AL250/52 Generator Idler Gearshaft – Life Limit ............................................................................. 21
DCA/AL250/53 4th Stage Turbine Nozzles – Life Limit ............................................................................ 21
DCA/AL250/54 Turbine & Compressor Assemblies – Inspection ............................................................ 22
DCA/AL250/55 Outer Combustion Case Assembly – Inspection ............................................................ 23
DCA/AL250/56 Compressor Mount Assembly – Inspection .................................................................... 25
DCA/AL250/57 Cancelled – FAA AD 2015-02-22 refers ......................................................................... 25
From 1 October 2012 the Civil Aviation Authority of New Zealand (CAA) will no longer rewrite the text of
State of Design ADs. Applicable State of Design ADs will be listed below and you can obtain them
directly from the National Airworthiness Authority (NAA) web sites. Links to the NAA web sites are
available on the CAA web site at http://www.caa.govt.nz/airworthiness-directives/states-of-design/ If
additional NZ ADs need to be issued when an unsafe condition is found to exist in an aircraft or
aeronautical product in NZ, they will be added to the list below. ...................................................................... 26
* 2015-02-22 Cancelled – FAA AD 2017-18-14 refers ......................................................................... 26
DCA/AL250/58 No. 5 Engine Bearing with P/N M250-10106 – Replacement ......................................... 26
* 2017-18-14 3rd and 4th Stage Turbine Wheels – Inspection ............................................................... 26
Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 3 of 26 CAA of NZ
DCA/AL250/1 Cancelled: Information now in Maintenance Manual
DCA/AL250/2 Cancelled: Once only inspection, purpose fulfilled
DCA/AL250/3 External Oil Sump Screen - Removal
Applicability: All 250-C18 and 250-C18A turbine assemblies as detailed
Requirement: Allison 250 CEB-24
Compliance: As detailed
Effective Date: 31 March 1968
DCA/AL250/4 Gasifier Turbine Oil Sump Screen - Removal
Applicability: All 250-C18 and 250-C18A turbine assemblies as detailed
Requirement: Allison 250 CEB-25
Compliance: As detailed
Effective Date: 31 March 1968
DCA/AL250/5 Cancelled - Information now in Maintenance Manual
DCA/AL250/6 Sixth Stage Compressor Blades - Modification
Applicability: All 250-C18 and 250-C18A compressor assemblies as detailed
Requirement: Allison 250 CEB-48
Compliance: Before further flight
Effective Date: 28 February 1969
DCA/AL250/7 Compressor Rotor, Second and Third Stage Wheel Assembly - Rework
Applicability: All 250-C18 and 250-C18A as detailed
Requirement: Allison 250 CEB-51
Compliance: By 31 December 1968
DCA/AL250/8 Compressor Case Assembly Vanes Leading Edge - Rework
Applicability: All 250-C18 and 250-C18A as detailed
Requirement: Allison 250 CEB-52
Compliance: By 31 December 1968
DCA/AL250/9 Compound Governor For PY Venting System - Modification
Applicability: 250-C18 and 250-C18A power turbine governors as detailed
Requirement: Allison 250 CEB-22
Compliance: By 31 May 1969
Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 4 of 26 CAA of NZ
DCA/AL250/10 Fuel Control Start Derichment Bellows - Modification
Applicability: As detailed
Requirement: Allison 250 CEB-83
Compliance: By 1 June 1969
DCA/AL250/11 Cancelled: Once only inspection, purpose fulfilled
DCA/AL250/12 Accessories Gear Box - Modification
Applicability: As detailed
Requirement: FAA AD 69-26-3
Compliance: As detailed
Effective Date: 30 March 1970
DCA/AL250/13 Compressor Wheels Stages 1-6 - Glass Bead Peen - Modification
Applicability: All compressor assemblies prior to 250-C18 CAC 21525B and 250-C18A CAC
21773B
Requirement: Allison 250 CEB-106
Compliance: By next overhaul
Effective Date: 28 February 1971
DCA/AL250/14 Compressor PC Filter Insert - Inspection
Applicability: As detailed
Requirement: Allison 250 CEB-112
Compliance: Every 25 hours TIS until modified
Effective Date: 28 February 1971
DCA/AL250/15 Compressor PC Filter Insert - Rework and Modification
Applicability: As detailed in Parts 1, 2 and 3 of CEB-112
Requirement: Allison 250 CEB-112
Compliance: As detailed
Effective Date: 28 February 1971
DCA/AL250/16 Cancelled: DCA/AL250/19A refers
DCA/AL250/17 Power Turbine Governor to Control Fuel Tube - Modification
Applicability: As detailed
Requirement: Allison 250 CEB-1040
(FAA AD 73-19-7 refers)
Compliance: Within the next 50 hours TIS
Effective Date: 31 October 1973
Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 5 of 26 CAA of NZ
DCA/AL250/18 Fuel Control Rigging - Inspection
Applicability: 250-C20 engines with Chandler Evans fuel controls
Requirement: FAA AD 74-14-03
Compliance: Within the next 25 hours TIS and thereafter at each change of the fuel control or the
associated linkage system
Effective Date: 24 July 1974
DCA/AL250/19A Critical Components - Life Limitations
Applicability: Models 250-B17 series, C18 series, -C20 series, -C28 series and -C30 series engines
Requirement: Life limits established for critical components are published in the following documents
and must be observed:
Model 250-B17 series, -C18 series and -C20 series - per corresponding Allison Gas
Turbine Operations and Maintenance Manual.
Model 250-C28 series - Per Allison CSL 2005
Model 250-C30 series - per Allison CSL 3005
Effective Date: DCA/AL250/19 - 20 July 1977
DCA/AL250/19A - 23 October 1987
DCA/AL250/20 Compressor Bleed Valve - Modification
Applicability: All model 250-C20 and 250-C20B
Requirement: Allison 250 CEB-1116
(FAA AD 77-09-08 refers)
Compliance: By 31 August 1977
DCA/AL250/21B Power Turbine Outer Coupling Nut - Inspection
Applicability: All model 250-B17, -C18 and -C20 series with power turbine coupling nut P/N
6846278 or 6871338
Requirement: Inspect coupling nut per Allison TP CSL 1030 Rev. 3 (250-B17), CSL 88 Rev. 3 (-C18)
or CSL 1060 Rev. 3 (-C20) as appropriate.
(FAA AD 77-15-12 refers)
Compliance: At intervals not exceeding 500 hours TIS, or one calendar year since installation in an
aircraft, except that initial inspection may be deferred for not more than next 100
hours TIS or 90 days from the effective date of this requirement, whichever occurs
first
Effective Date: DCA/AL250/21A - 12 May 1978
DCA/AL250/21B - 11 March 1983
Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 6 of 26 CAA of NZ
DCA/AL250/22C Turbine Wheel - Inspection, Retirement and Operating Limitation
Applicability: All model 250-C20, -C20B, -C20C, -B17, -B17B, AND -B17C with following slotted
third stage turbine wheels:
Part No.
Type of Shroud
6887113
Full Slot
6888633
Full Slot
6896863
Crimped Full Slot
6898551
Centre Slot
6898567
Centre Slot
6898733
Centre Slot
6898743
Centre Slot
6898753
Centre Slot
6898763
Centre Slot
6898823
Crimped Full Slot
6899364
Crimped Full Slot
6899406
Crimped Centre Slot
6899415
Crimped Centre Slot
6899416
Crimped Centre Slot
6899417
Crimped Centre Slot
6899418
Crimped Centre Slot
6899419
Crimped Centre Slot
Requirement: To preclude possible engine power loss resulting from partial blade and/or shroud
separation of slotted third stage turbine wheels, accomplish the following:
1. Remove, inspect, return to service where applicable and ultimately retire from
service affected turbine wheels per Allison CEB-A-1174/1146 Rev. 3.
2. Install following placards on aircraft instrument panel:
(a) Adjacent to tachometer `Avoid continuous operation 90 percent to 98 percent N2'.
(b) In clear view of pilot appropriate ground running precautions applicable to engine
models affected, per Allison CEB-A-1174/1146 Rev. 3.
(FAA AD 83-03-02R1 refers)
Compliance: 1. Inspection, replacement and retirement - as prescribed in Allison CEB-A-
1174/1146 Rev. 3 Compliance Schedule.
2. Placards - by 10 May 1983 if not already accomplished.
Effective Date: DCA/AL250/22B - 11 March 1983
DCA/AL250/22C - 6 April 1984
DCA/AL250/23 Fuel Pump LP Filter Element - Replacement Fuel Pump HP Filter Assembly -
Installation
Applicability: All model 250-C20 engine assemblies P/N 6851480 and 6853341. All model 250-
C20B engine assemblies P/N 6886440
Requirement: 1. Replace 10 Micron LP fuel filter element with 5 Micron element per Allison CEB-
1092
2. Install HP fuel filter assembly per Allison CEB-1095
(Allison 250-C20/C20B CSL 1061 refers)
Compliance: By 30 September 1978
Effective Date: 23 June 1978
Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 7 of 26 CAA of NZ
DCA/AL250/24 Fuel Pump Drive - Inspection
Applicability: All model 250-C18 series and 250-C20 series with fuel pump P/N 6854292, 6856250,
6857548, 6876803 and 6877719
Requirement: To prevent flameout due to spline failure:
1. Inspect per Allison CSL 61 for 250-C18 series and CSL 1007 for 250-C20 series
2. Modify per Allison CSB 161 for 250-C18 series and CSB 1051 for 250-C20 series
(FAA AD 78-14-08 refers)
Compliance: 1. Inspection - prior to 225 hours TTIS and thereafter at intervals not exceeding 200
hours TIS. Pumps which have exceeded 200 hours TTIS shall be initially inspected
within the next 25 hours TIS
2. Modification - prior to 1500 hours TTIS. Pumps which have exceeded 1475 hours
TTIS within the next 25 hours TIS
Effective Date: 22 July 1978
DCA/AL250/25 Compressor Wheels - Retirement
Applicability: All model 250-C18 with fourth stage compressor wheels P/N 6856754 or 6871444 in
S/N range C01408 through C02321 as detailed in Allison 250-C18 CSL-96
Requirement: Remove from service all affected compressor wheels per Allison 250-C18 CSL-96
Compliance: Within the next 100 hours TIS
Effective Date: 31 August 1979
DCA/AL250/26A Turbine Wheels - Removal
Applicability: All model 250-B17, B17B, B17C, C20, C20B, and C20C engines with third stage
turbine wheels P/N 6898551, 6898567, 6898733, 6898743, 6898753, 6898763,
6896863, 6898823, 6899364, 6899406, 6899415, 6899416, 6899417, 6899418 and
6899419
Requirement: To preclude possible engine power loss resulting from third stage turbine wheel
failure, remove turbine wheels from service if following temperature time limits are
exceeded and install a serviceable approved P/N turbine wheel
Temperature Range
Time Limit
810°C to 927°C
10 seconds max.
(1490°F to 1700°F)
Over 927°C
0 seconds
(1700°F)
(Allison CSL 1051 Rev. 3, CSL 1084 Rev. 3 and FAA AD 79-21-01R1 refer)
Note: Time at temperature limits is not additive and may be repeated without
restriction
Compliance: Before further flight when hot start beyond established limits experienced except that
aircraft may be flown to a base where removal can be performed
Effective Date: DCA/AL250/26 - 1 November 1979
DCA/AL250/26A - 24 July 1981
Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 8 of 26 CAA of NZ
DCA/AL250/27 N2 (Electronic) Overspeed Control System - Deactivation
Applicability: All model 250-C28B engines installed in, but not limited to, Bell Model 206L-1
rotorcraft
Requirement: To preclude possible engine power loss resulting from intermittent or spurious
activation of N2 (Electronic) overspeed control system, accomplish the following:
1. (a) Pull aircraft installed N2 overspeed circuit breaker and secure by wrapping
with tape or placing `Ty-wrap' (or equivalent) around breaker stem.
(b) Adjacent to N2 overspeed circuit breaker install placard which, in letters at
least ¼ inch high states: "ENG OVSP CIRCUIT DEACTIVATED".
2. Install P/N AN814-4DL or alternative plug and P/N AS3084-04 packing in outlet
port of N2 overspeed solenoid valve. Tighten and safety with lockwire.
(FAA AD 82-03-02 refers)
Compliance: Before further flight unless already accomplished
Effective Date: 12 March 1982
DCA/AL250/28 HP Fuel Control Filter - Modification
Applicability: All model 250-C20 and C20B with CECO fuel system
Requirement: Modify engine high pressure fuel control filter assembly P/N 6895173 or 6896727 to
P/N 6899279 per Allison 250 CEB-A-1144
(FAA AD 82-13-03 refers)
Compliance: By 1 October 1982
Effective Date: 30 July 1982
DCA/AL250/29A Engine Fuel and Control System – Inspection
Applicability: All model 250 series engines fitted with bendix fuel control and power turbine governor
assemblies containing, or suspected of containing bushing assemblies P/N 2526146
with a nylon ball bearing separator.
Note: This AD amended to include Allison CEB-A-73-3021 which is applicable to model 250-
C30, -C30P and –C30S engines.
Requirement: Inspect per Allison 250 CEB-A-229, CEB-A-1206, CEB-A-1166, CEB-A-73-2026 or
CEB-A-73-3021 as applicable, and replace any bushing assembly which has a nylon
ball bearing separator with an assembly containing a steel ball bearing separator.
(FAA AD 82-24-05 refers)
Compliance: As prescribed in the requirement documents.
Effective Date: DCA/AL250/29 - 28 January 1983
DCA/AL250/29A - 26 June 2008
Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 9 of 26 CAA of NZ
DCA/AL250/30 Turbine Assembly, Splined Adaptor Locknut - Inspection
Applicability: Models 250-C28B, -C28C and -C30 series engines with following turbine S/Ns CAT
70001 through 70802 and 70804; CAT 28001 through 28046; CAT 90001 through
95436 and 95438
Requirement: Inspect splined adaptor locknut torque per Allison 250-C28/C30 CEB-A-72-2132/3146.
(FAA AD 86-20-13 refers)
Compliance: Within the next 5 hours TIS unless already accomplished
Effective Date: 24 April 1987
DCA/AL250/31 Turbine Assembly - Modification
Applicability: Model 250-C30 series with turbine S/Ns detailed in Allison CEB-A-72-3128 Rev. 1 and
CEB-A-72-3137 Rev. 2
Requirement: To preclude possibility of a gas producer uncontained turbine rotor failure, accomplish
the following:
1. Install first stage turbine wheel internal energy absorbing ring P/N 23031909, or
23032263 per Allison CEB-A-72-3128 Rev. 1.
2. Replace second stage turbine wheel P/N 6892762, or 6898922, or 23004233 with
P/N 23032280 per Allison CEB-A-72-3137 Rev. 2.
(FAA AD 86-19-12 refers)
Compliance: By 30 November 1987
Effective Date: 23 October 1987
DCA/AL250/32A Gas Producer Oil Tube - Modification
Applicability: All model 250-C30 series with turbine S/Ns detailed in Allison CEB-A-72-3165
Requirement: To preclude possibility of engine oil loss, modify No. 8 bearing oil supply tube
assembly per Allison CEB-A-72-3165.
(FAA AD 88-07-06 refers)
Compliance: By 31 July 1988
Effective Date: DCA/AL250/32 - 23 October 1987
DCA/AL250/32A - 5 July 1988
DCA/AL250/33 Fuel Control - Removal
Applicability: Model 250-B17, -C20, -C20R and -C30 series with bendix gas producer controls listed
in Allison CEB-A-1231, -A-1272, -A-73-4008 and -A-73-3042 respectively
Requirement: To prevent possible engine over-temperature, loss of throttle response or
unscheduled power increase, remove affected fuel controls from service.
(FAA AD 88-17-01 refers)
Compliance: By 9 June 1989
Effective Date: 12 May 1989
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Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 10 of 26 CAA of NZ
DCA/AL250/34 Second Stage turbine Nozzle - Modification
Applicability: Model 250-C28B, except those with turbine S/N CAT 70498, CAT 70499, CAT 70502,
CAT 70513 and subsequent
Model 250-C28C except those with turbine S/N CAT 28010 and subsequent
Requirement: To prevent failure of the second stage turbine nozzle and possible uncontained
turbine wheel failure, modify and re-identify second stage turbine nozzle P/N 6898952
into P/N 23001942 per Allison CEB-A-72-2044 Rev. 4.
(FAA AD 89-23-12 refers)
Compliance: Within the next 100 hours TIS, or at the next turbine repair or overhaul, whichever
occurs first, but not later than June 30, 1990
Effective Date: 30 March 1990
DCA/AL250/35 Scavenge Line Air/Oil Separator Assembly - Installation
Applicability: Model 250-C28B, S/N CAE 860011 through CAE 860787 with turbine S/N CAT 70011
through 70804
Requirement: To improve venting of the No. 8 bearing oil sump install No. 8 bearing scavenge line
air/oil separator assembly, P/N 23034772 per Allison CEB-A-72-2138 Revision 1.
(FAA AD 86-16-03 refers)
Compliance: By 31 March 1991
Effective Date: 21 December 1990
DCA/AL250/36B Unapproved Components - Removal
Applicability: Model 250 series fitted with any of the following components.
Power Turbine Governor
P/N 23005491
Serial Number:
4493
Power Turbine Governor
P/N 2524769-11
Serial Number:
24924
Turbine disk #1
P/N 6886407
Serial Number:
X108906
X69846
X90633
Turbine disk #2
P/N 6877092
Serial Number:
X32096
Turbine disk #2
P/N 6898782
Serial Number:
AD84185
Requirement: To prevent possible in-service failure of unapproved components, remove the
components listed from service.
Any of the components listed held as spares must not be fitted to any engine.
Compliance: Before further flight.
Effective Date: DCA/AL250/36A - 27 November 1996
DCA/AL250/36B - 14 February 1997
Engines Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 11 of 26 CAA of NZ
DCA/AL250/37 Superior Air Parts Bearings - Inspection
Applicability: Model 250-B15G, -B17F, -B17F/1, -B17F/2, -C20, -C20B, -C20F, -C20J, -C20S, -
C20W, -R, -C20R/1, -C20R/2, -C20R/4, -C28B, -C28C, -C30, -C30P, -C30M, and -
C30G turbine engines, with Superior Air Parts, Inc. Parts Manufacture Approval (PMA)
bearings, P/N A6871505 and/or P/N A23007152, installed.
These engines are installed on, but not limited to the following aircraft:- ASTA N-22
and N-24 series, Bell 206 series, Eurocopter AS355 series, Hiller UH12 series (Soloy
Conversions) and McDonnell Douglas 369 series.
Requirement: To prevent bearing failure due to bearing separator instability, which can result in
subsequent turbine and engine failure, accomplish the following:-
1. For engines with No. 5 bearings, Superior P/N A6871505 installed:-
(a) Perform an initial visual inspection of all engine filters for metal particles per
Superior Turbine SB T95-SB001, Rev A. If any engine filter contains metal particles
that exceed the return to service criteria described in the SB, prior to further flight
remove the No. 5 bearing, Superior P/N A6871505, and replace with a serviceable
No. 5 bearing, Allison P/N 6871505.
(b) Thereafter, for engines with No. 5 bearing, Superior P/N A6871505 installed,
perform visual inspections of all engine filters for metal particles per SB T95-SB001
Rev A, and if necessary replace with serviceable parts.
2. For engines with No. 8 bearings, Superior P/N A23007152 installed:-
(a) Perform an initial visual inspection of all engine filters for metal particles per SB
T95-SB002 Rev A. If any engine filter contains metal particles that exceed the return
to service criteria described in the SB, prior to further flight remove the No. 8 bearing,
Superior P/N A23007152, and replace with a serviceable No. 8 bearing, Allison P/N
23031478.
(b) Thereafter, for engines with No. 8 bearing, Superior P/N A23007152 installed,
perform visual inspections of all engine filters for metal particles per SB T95-SB002
Rev A, and if necessary replace with serviceable parts.
3. Remove the No. 5 bearing, Superior P/N A6871505, and replace with a serviceable
No. 5 bearing, Allison P/N 6871505; and remove the No. 8 bearing, Superior P/N
A23007152, and replace with a serviceable No. 8 bearing, Allison P/N 23031478. This
constitutes terminating action to the inspection requirements of this AD.
(FAA AD 96-19-01 refers)
Compliance: 1. (a) Within the next 20 days.
(b) For engines with 300 hours or less TIS since overhaul, or TSN if never
overhauled, perform inspections at intervals not to exceed 25 hours TIS since last
inspection.
For engines with more than 300 hours TIS since new or overhaul, whichever is lesser,
perform inspections at intervals not to exceed 100 hours TIS since last inspection.
2. (a) Within the next 20 days.
(b) For engines with 300 hours or less TIS since overhaul, or TSN if never
overhauled, perform inspections at intervals not to exceed 25 hours TIS since last
inspection.
For engines with more than 300 hours TIS since new or overhaul, whichever is lesser,
perform inspections at intervals not to exceed 100 hours TIS since last inspection.
Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 12 of 26 CAA of NZ
3. At the next engine overhaul, repair or maintenance when disassembly permits
replacement of the bearing, whichever occurs first.
Effective Date: 25 October 1996
DCA/AL250/38A Electrical Harness, HMU and ECU - Replacement
Applicability: Model 250-C47B engines, installed on but not limited to Bell Model 407 helicopters.
Requirement: To prevent uncommanded in-flight engine shutdowns, which can result in autorotation,
forced landing, and possible loss of the helicopter, accomplish the following:-
1. Replace the engine main electrical harness assembly,
P/N 23062796, with an improved assembly, P/N 23065805, per Allison Alert
Commercial Engine Bulletin (CEB) CEB-A-73-6010.
2. Install a new hydromechanical unit and engine control unit per Allison CEB-A-73-
6015, Revision 1, or Revision 2.
3. Remove the “OVRSPD SYSTEM INOP” placard required by paragraph (d) of AD
96-24-09, and revise the Flight Manual by removing the pages added by paragraph (f)
of AD 96-24-09, and incorporate BHTC Flight Manual BHT-407-FM-1, Revision 5,
dated June 24, 1997.
4. Install a corrosion resistant electronic control unit (ECU) per Allison CEB-A-73-
6017, Revision 1, or Revision 2. Installation of a corrosion resistant ECU in
accordance with this paragraph will satisfy the requirement in paragraph 2 of this AD
to install a new ECU.
(FAA AD 98-10-03 refers)
Compliance: 1. Prior to further flight.
2. Prior to 31 January 1998.
3. Prior to further flight after completing the requirements of paragraph 2 of this AD.
4. By 17 August 1998.
Effective Date: DCA/AL250/38 - 19 December 1997
DCA/AL250/38A - 3 July 1998
DCA/AL250/39 Fuel Control Bellows - Replacement
Applicability: Model 250-B15, 250-B17, 250-B17F, series turboprop engines and 250-C18, 250-
C20, 250-C20R, 250-C28, 250-C30 series turboshaft engines.
Requirement: To prevent main fuel control (MFC) bellows assembly leakage, which can result in an
uncommanded minimum fuel flow condition and subsequent loss of engine fuel flow
control, accomplish the following:-
Replace existing beryllium copper MFC bellows assemblies, P/Ns 2523722, 2539647,
2540539, 2540767, and 2542526, with Inconel 718 stainless steel welded MFC
bellows assemblies, P/N 2543598, per Allison CEB-A-282/AlliedSignal Aerospace
Equipment Systems SB GT-242, Revision 2.
(FAA AD 98-24-28 refers)
Note: Allison CEB-A-282, Revision 2, dated April 15, 1998, also serves as CEB-A-
1329 for the 250-C20 series engines, CEB-A-73-2053 for the 250-C28 series engines,
CEB-A-73-3068 for the 250-C30 series engines, CEB-A-73-4029 for the 250-C20R
series engines, Turboprop (TP) CEB-A-158 for the 250-B15G series engines, TP
CEB-A-1286 for the 250-B17 series engines, and TP CEB-A-73-2014 for the 250-
B17F series engines.
Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 13 of 26 CAA of NZ
Compliance: At the earlier of the following:-
The next time the MFC is being repaired or overhauled, or
By 31 March 1999 for all MFCs listed by P/Ns in Tables 1 and 2 of the CEB/SB.
By 31 August 1999 for all MFCs listed by P/Ns in Table 3 of the CEB/SB.
By 31 October 1999 for all MFCs listed by P/Ns in Tables 4 and 5 of the CEB/SB.
Effective Date: 15 January 1999
DCA/AL250/40A Torquemeter - Replacement
Applicability: Models 250-C20, -C20B, -C20F, -C20J, -C20R, -C20R/1, -C20R/2, -C20S and –
C20W turboshaft engines and 250-B17, -B17C, -B17D, -B17E, -B17F, -B17F/1, and
B17F/2 turboprop engines.
Note: This revision to the AD, adds model 250-C20J.
Requirement: To prevent uncontained engine failure, engine failure and possible fire, accomplish the
following:-
Replace helical torquemeter gearshaft assemblies P/N 23035299 or 23038191 that
have less than 100 hoursTSN, with a serviceable torquemeter. For the purposes of
this AD the following torquemeter assemblies are considered serviceable;
(1) P/N 23035299 or 23038191 that have greater than 100 hours TSN.
(2) A torquemeter assembly with a P/N other than 23035299 or 23038191.
(FAA AD 2001-24-12 refers)
Compliance: Before further flight unless already accomplished.
Effective Date: DCA/AL250/40 – 3 October 2001
DCA/AL250/40A – 20 December 2001
DCA/AL250/41 Third Stage Turbine – Life Limitation
Applicability: Model 250-C28, -C28B and –C28C with third stage turbine wheels P/N 6899383 and
one of the following S/Ns.
HX91428R
HX91471R
HX91489R
HX91512R
HX91707R
HX91736R
HX91456R
HX91472R
HX91490R
HX91513R
HX91708R
HX91738R
HX91457R
HX91473R
HX91492R
HX91519R
HX91709R
HX91742R
HX91458R
HX91474R
HX91493R
HX91520R
HX91710R
HX91744R
HX91459R
HX91475R
HX91494R
HX91522R
HX91711R
HX91748R
HX91461R
HX91477R
HX91500R
HX91523R
HX91712R
HX91749R
HX91462R
HX91478R
HX91501R
HX91524R
HX91713R
HX91750R
HX91464R
HX91480R
HX91503R
HX91525R
HX91714R
HX91754R
HX914659
HX91482R
HX91504R
HX91526R
HX91715R
HX91764R
HX91465R
HX91483R
HX91506R
HX91527R
HX91721R
HX91765R
HX91466R
HX91485R
HX91507R
HX91528R
HX91722R
HX91766R
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 14 of 26 CAA of NZ
HX91467R
HX91486R
HX91508R
HX91529R
HX91726R
HX91767R
HX91468R
HX91487R
HX91510R
HX91530R
HX91733R
HX91768R
HX91469R
HX91488R
HX91511R
HX91706R
HX91735R
HX91769R
Requirement: To prevent failure of the third stage turbine leading to loss of power and damage to
the airframe, remove the above listed turbine wheels from service per the following :
For 3rd stage turbine wheel
Remove by
With fewer than 3,000 cycles-since-new
(CSN), and fewer than 1,500 hours time-
since-new (TSN).
3,000 CSN or 1,500 hours TSN,
whichever occurs earlier.
With between 3,000 and 6,000 CSN, and
fewer than 1,500 hours TSN.
200 additional cycles.
With fewer than 3,000 CSN, and between
1,500 and 3,000 hours TSN
100 additional hours.
With between 3,000 and 6,000 CSN and
between 1,500 and 3,000 hours TSN
200 additional cycles or 100 additional
hours, whichever occurs earlier
With more than 6,000 CSN, or more than
3,000 hours TSN
Before further flight
(FAA AD 2002-06-08 refers)
Compliance: As detailed in table above.
Effective Date: 26 April 2002
DCA/AL250/42 Cancel DCA/AL250/43 refers
Effective Date: 27 January 2005
DCA/AL250/43 Cancelled - DCA/AL250/50 refers
Effective Date: 31 August 2006
DCA/AL250/44 Power lever Angle Potentiometer - Inspection
Applicability: Rolls-Royce Corporation (RRC, formerly Allison Engine Company, Allison Gas
Turbine Division, and Detroit Diesel Allison),
Models 250-C30R/3, -C30R/3M, -C47B, and -C47M turboshaft engines that have a
hydromechanical unit (HMU) with a P/N listed in 1.A. Group A of RRC Alert
Commercial Engine Bulletins No. CEB A-73-3103, Revision 4, and No. CEB A-73-
6030, Revision 4,
Note: These engines are installed on, but not limited to, Bell OH-58D, Bell Helicopter
Textron 407, Boeing AH/MH-6M, and MD Helicopters Inc. 600N helicopters.
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 15 of 26 CAA of NZ
Requirement: This AD supersedes DCA/AL250/42 and results from the manufacturer releasing a
redesigned HMU that has a dual-element potentiometer. This AD retains the initial and
repetitive inspections of DCA/AL250/42 but replacement of the HMU with the
redesigned unit is now terminating action for this AD.
To prevent uncommanded and sudden changes in engine power accomplish the
following:
1. Perform an initial electrical signal inspection of the HMU Power Lever Angle
(PLA) potentiometer IAW paragraphs 2.B. through 2.B.(8) and 2.B.(10) of the
Accomplishment Instructions of RRC ACEB No. CEB A-73-3103, Revision 4, or No.
CEB A- 73-6030, Revision 4. Replace the HMU before further flight if the electrical
signal inspection result is unacceptable.
2. Replace the HMU with an HMU that has a P/N not specified in this AD within 600
FH after the effective date of this AD, or January 31, 2005, whichever occurs earlier.
Replacement with a unit with a P/N outside the range effected by this AD terminates
the repetitive inspection requirement specified in paragraph 1.
(FAA AD 2004-24-04 refers)
Compliance: 1. Within 100 hours TIS, or 300 hours TIS since inspection per DCA/AL250/42,
whichever occurs later, and thereafter at intervals not to exceed 300 hours between
inspections.
2. Within 600 hours TIS.
Effective Date: 27 January 2005
DCA/AL250/45 C28 3rd Stage Turbine Wheels – Life Limitation
Applicability: Rolls-Royce Corporation (formerly Allison Engine Company, Allison Gas Turbine
Division, and Detroit Diesel Allison) models 250-C28, -C28B, and -C28C turboshaft
engines with third-stage turbine wheels, P/N 6899383, with the following S/Ns:
TABLE 1.—SNs OF AFFECTED THIRD STAGE TURBINE WHEELS
HX91922 X523242 X523281
HX91923 X523243 X523283
HX91925 X523244 X523284
HX91926 X523246 X523287
HX91928 X523249 X523288
HX91929 X523250 X523289
HX91930 X523251 X523290
HX91932 X523253 X523291
HX91934 X523255 X523292
HX91936 X523257 X523293
HX91937 X523260 X523294
HX91939 X523261 X523295
HX91940 X523262 X523296
HX91960 X523263 X523297
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 16 of 26 CAA of NZ
HX91962 X523264 X523298
HX91966 X523265 X523300
HX91976 X523266 X523305
HX91977 X523268 X523309
HX91979 X523269 X523313
HX91980 X523270 X523315
X523236 X523271 X523317
X523237 X523273 X523319
X523238 X523276 X523320
X523239 X523277
X523241 X523278
These engines are installed on, but not limited to, Bell Helicopter Textron 206L-1;
Eurocopter Deutschland BO 105 LS A-1; and Eurocopter Canada BO 105 LS A-3
helicopters. (FAA AD 2004-14-02)
Requirement: To prevent power loss and uncommanded engine shutdown due to failure of the third-
stage turbine wheel blade and shroud, replace effected 3rd stage turbine wheels as
specified below.
Compliance: For any third-stage turbine wheel with fewer than 250 hours TSN, replace turbine
wheel before accumulating 300 hours TSN.
For any third-stage turbine wheel with 250 or more hours TSN on the effective date of
this AD, replace turbine wheel before accumulating an additional 50 hours TIS.
Effective Date: 24th February 2005
DCA/AL250/46B Compressor Couplings – Removal from Service
Applicability: Rolls-Royce Corporation (formerly Allison Engine Company, Allison
Gas Turbine Division and Detroit Diesel Allison) 250-B17, -B17B, -B17C, -B17D, -
B17E, 250-C20,-C20B, -C20F, -C20J, -C20S and -C20W series turboprop and
turboshaft engines fitted with the following compressor adaptor couplings:
Alcor Engine Company P/N 23039791AL and 23039791AL–1/–2/–3, and
Extex Ltd P/N A23039791, E23039791, E23039791–1/–2/–3,
EH23039791 and EH23039791–1/–2/–3, and
Rolls-Royce Corp P/N 23039791–1/–2/–3, and
Superior Air Parts P/N A23039791.
Note: DCA/AL250/46B revised to extend the compliance (i.e. the replacement) for RRC
compressor adaptor couplings P/N 23039791-1, -2 and -3 to 1 March 2017. There is
no change to the AD requirement.
Requirement: To prevent compressor adaptor coupling failure which could result in an engine
shutdown, accomplish the following:
1. Alcor compressor adaptor couplings:
Replace Alcor compressor adaptor couplings P/N 23039791AL, 23039791AL-1, -2
and -3.
![](asset-11.png)
Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 17 of 26 CAA of NZ
2. Extex and SAP compressor adaptor couplings:
Replace Extex and SAP compressor adaptor couplings P/N A23039791, E23039791,
E23039791-1, -2 and -3, EH23039791 and EH23039791-1, -2 and -3.
3. Rolls-Royce Corporation (RRC) compressor adaptor couplings:
Replace RRC compressor adaptor couplings P/N 23039791-1, -2 and -3.
(FAA AD 2004-26-09 and FAA AMOC dated 24 Feb 2012 refer)
Compliance: 1. For Alcor compressor adaptor couplings:
For couplings with 600 or more hours TSN, or unknown operating hours that cannot
be determined, replace affected couplings at the next access or within 300 hours TIS
from 8 March 2005 (the effective date of DCA/AL250/46A) whichever occurs sooner.
For couplings with fewer than 600 hours TSN, replace couplings at the next access or
before exceeding 900 hours TSN whichever occurs sooner.
2. Extex and SAP compressor adaptor couplings:
For couplings with unknown operating hours that cannot be determined and couplings
with 600 or more hours TSN, replace affected couplings at the next access or within
300 hours TIS from 8 March 2005 (the effective date of DCA/AL250/46A) whichever
occurs sooner.
For couplings with fewer than 600 hours TSN, replace affected couplings at the next
access or before exceeding 900 hours TIS whichever occurs sooner.
3. RRC compressor adaptor couplings:
Replace affected couplings the next time the compressor rotor is disassembled for
any reason, or by 1 March 2017 whichever occurs sooner.
Effective Date: DCA/AL250/46 - 24 February 2005
DCA/AL250/46A - 8 March 2005
DCA/AL250/46B - 29 March 2012
DCA/AL250/47 Turbine Wheel Energy Absorbing Ring - Installation
Applicability: Model 250-B17B, B17C, -B17D, -B17E, -C20, -C20B, - C20F, -C20J, -C20S, and -
C20W turboprop and turboshaft engines that are not fitted with a turbine energy
absorbing ring, P/N 23035175, or an equivalent approved turbine energy absorbing
ring.
These engines are installed on, but not limited to Aerospatiale AS 355F1, Agusta
AB206B, Bell 206B, Bell 206L, Bolkow BO 105 DBS-4, Hiller UH-12E, GAF N24A,
Hughes 369D, Hughes 369E and Hughes 369HS aircraft.
Requirement: To minimize the risk of uncontained 1st stage turbine wheel fragments from causing
damage to the aircraft or damage to the second engine on twin-engine installations,
which could lead to loss of control of the aircraft, install a turbine energy absorbing
ring, P/N 23035175, or an equivalent approved turbine energy absorbing ring, in the
plane of the 1st stage turbine wheel, per paragraphs 1.M., 2.A., and 2.B. of Rolls-
Royce Corporation Alert Commercial Engine Bulletin CEB-A-1255, revision 4.
(FAA AD 2005-10-13 refers)
Compliance: At the next disassembly of the turbine rotor module, or within 1750 hours time since
new, overhaul, heavy maintenance or last hot section inspection, whichever occurs
first, but no later than 31 October 2011, unless already accomplished.
Effective Date: 30 June 2005
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 18 of 26 CAA of NZ
DCA/AL250/48 Third Stage Turbine Wheels – Inspection
Applicability: All model 250-C28, -C28B and -C28C turboshaft engines.
Requirement: To prevent failure of the third-stage turbine wheel resulting in loss of power and
possible uncommanded engine shutdown, remove the third-stage turbine wheel P/N
6899383, and inspect the seal joint in each passage between airfoils at the hub and
shroud, per Rolls-Royce Corporation Alert Service Bulletin CEB-A-72-2205. Replace
unserviceable turbine wheels, before further flight.
(FAA AD 2005-20-11 refers)
Compliance: For third-stage turbine wheels with less than 3000 hours TSN, inspect at next
exposure of third-stage turbine wheel, or by 1 July 2007, whichever occurs sooner.
For third-stage turbine wheels with 3000 hours or more TSN, inspect within 300 hours
TIS, or by 1 July 2007, whichever occurs sooner.
Effective Date: 1 December 2005
DCA/AL250/49 Gas Producer Rotor Assembly Tie Bolts - Replacement
Applicability: Model 250-B17, 250-B17B, 250-B17C, 250-B17D, 250-B17E, 250-B17F, 250-B17F/1,
250-B17F/ 2, 250-C18, 250-C20, 250-C20B, 250-C20F, 250-C20J, 250-C20R, 250-
C20R/1, 250-C20R/2, 250-C20R/4, 250-C20S and 250-C20W series turboprop and
turboshaft engines fitted with gas producer rotor assembly tie bolt P/Ns listed in the
following table:
Manufacturer:
Affected Part Numbers:
Extex Ltd. (EXTEX)
A23008020 and E23008020
Rolls-Royce Corporation (RRC)
23008020, 6843388 and 6876991
Superior Air Parts Inc. (SAP)
A23008020
Pacific Sky Supply Inc
23008020P
These engines are installed on, but not limited to Bell 206A, 206B, 206C, McDonnell
Douglas 369D, 369E, 369F, 369H, 369HS, Schweizer 269D, GAF N24A and
Eurocopter AS355E, AS355F, AS355F1, AS355F2 aircraft.
Requirement: To prevent tie bolt failure which could cause loss of engine power due to overspeed of
the first stage turbine wheel, replace the gas producer rotor assembly tie bolts with
P/Ns that are not listed in the applicability table of this AD, per Rolls-Royce
Corporation Commercial Engine Bulletin CEB A-304, CEB A-1371, CEB A-72-4076,
TP CEB A-176, TP CEB A-1319 or TP CEB A-72-2027 as applicable.
Note: Do not install gas producer rotor assembly tie bolts with P/Ns as listed in table 1 to any
model 250-B or 250-C series engine.
(FAA AD 2006-13-06 refers)
Compliance: At the next turbine repair or overhaul, or by 31 October 2011 whichever occurs
sooner.
Effective Date: 27 July 2006
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 19 of 26 CAA of NZ
DCA/AL250/50 Fuel Nozzle Screen – Inspection
Applicability: Model 250-B and 250-C series turboshaft and turboprop engines as follows:
-B15A, -B15E, -B15G, -B17, -B17B, -B17C, -B17D, -B17E, -B17F, -B17F/, -B17F/2,
-C18, -C18A, -C18B, -C18C, -C20, -C20B, -C20C, -C20F, -C20J, -C20R, -C20R/1,
-C20R/2, -C20R/4, -C20S, -C20W, -C28, -C28B, -C28C, -C30, -C30G, -C30G/2,
-C30M, -C30P, -C30R, -C30R/1, -C30R/3, -C30R/3M, -C30S, -C30U, -C40B, -C47B
and -C47M.
These engines are installed on, but not limited to, Bell Helicopter Textron models
206A, 206B, 206L, 206L-1, 206L-3, 206L-4, 407 and 430, Eurocopter France models
AS355E, AS355F, AS355I and AS355F2, Eurocopter Deutschland Models BO-105A,
BO-105C, BO-105S and BO-105LS A-1, McDonnell Douglas 369D, 369E, 369F,
369H, 369HE, 369HM, 369HS, 369FF and 500N, Schweizer TH269D and Sikorsky S-
76A aircraft.
Requirement: To minimize the risk of sudden loss of engine power and uncommanded engine
shutdown, due to the possible collapse of the screen in the fuel nozzle, accomplish
the following;
1. For engines fitted with the following fuel nozzles, inspect per the applicable Rolls-
Royce Corporation Alert Commercial Engine Bulletins (CEB):
Manufacturer
P/N
Corresponding RRC vendor P/N
RRC
6874959
5232815
6894610
5233465
6898531
5233585
Goodrich Delavan
(Parts Manufacturer
Approval) PMA
47069
N/A
47101
N/A
49445
N/A
If contamination is found on the screen, inspect and clean the entire aircraft fuel
system, per the applicable CEB, before further flight.
2. For engines fitted with the following fuel nozzles, inspect per the applicable CEB:
Manufacturer
P/N
Corresponding RRC vendor P/N
RRC
6852020
5232480
6890917
5233333
6899001
5233600
If contamination is found on the screen, inspect and clean the entire aircraft fuel
system, per the applicable CEB, before further flight.
Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 20 of 26 CAA of NZ
3. Replace all fuel nozzles listed in requirements 1 and 2 with a fuel nozzle P/N
which is not listed in this AD.
(FAA AD 2006-16-04 refers)
Note 1: If the inspection of RRC fuel nozzles P/Ns 6852020, 6890917 and 6899001 has been
accomplished per DCA/AL250/43 (FAA AD 2004-24-09 refers), then requirement 2
has been accomplished.
Note 2: Service information related to the requirements of this AD can be found in Rolls-
Royce Corporation Alert Commercial Engine Bulletins CEB–A–313, CEB–A–73–2075,
CEB–A–1394, CEB–A–73–3118, CEB–A–73–4056, CEB–A–73–5029, CEB–A–73–
6041, TP CEB–A–183, TP CEB–A–1336 and TP CEB–A–73–2032, as applicable.
Compliance: 1. Within the next 50 hours TIS.
2. Within the next 150 hours TIS, unless already accomplished per DCA/AL250/43.
3. At the next fuel nozzle overhaul.
Effective Date: 31 August 2006
DCA/AL250/51A Third and Fourth Stage Turbine Wheels – Speed Range Life Limitation
Applicability: Models 250- C30, -C30G, -C30G/2, -C30M, -C30P, -C30R, -C30R/1, -C30R/3, -C30R/
3M, -C30S, -C30U, -C40B, -C47B and -C47M turboshaft engines, fitted with third-
stage turbine wheels, P/Ns 6898663 or 23065843, or a fourth-stage turbine wheel
P/Ns 6892764 or 23066744.
These engines are installed on, but not limited to, Bell 206L-3, Bell 206L-4, Bell 230,
Bell 407, Bell 430, MDHI 369F, MDHI 369FF, MDHI 600N and Sikorsky S-76A
helicopters.
Note 1: AD amended to include note 3 and 4.
Requirement: To prevent the possibility of uncontained engine failure or loss of engine power or
engine shutdown, replace the third and fourth-stage turbine wheels after the turbine
wheels have entered the speed event range for the sixth time.
To determine the turbine speed event range refer to the instruction in paragraph 2.A.
through 2.A.(5) and the applicable figures 1 through to 5 of Rolls Royce Corporation
Alert Commercial Engine Bulletins (CEBs) No. CEB A-72-3272, No. CEB A-72-5048
and No. CEB A-72-6054 (combined in one document), revision 2.
Record every occurrance when the third and fourth-stage turbine wheels enters the
speed range between "Event Threshold" and "Maximum Overspeed Transient".
Note 2: The turbine wheels are only allowed to enter the speed range between "Event
Threshold" and "Maximum Overspeed Transient" five times. After the sixth event, the
turbine wheels must be replaced.
Note 3: Sign engine logbook for AD compliance at time of adding the inspection requirement
to the aircraft tech log. Also add the retirement criteria in this AD to the engine
logbook in Section 3 Engine Component Record.
Note 4: The pilot must record every event when the turbine wheels have entered the speed
range between "Event Threshold" and "Maximum Overspeed Transient".
(FAA AD 2006-20-07 refers)
Note 5: The retirement criteria in this AD are in addition to the existing third- and fourth-stage
turbine wheel hour and cycle life limitations. Turbine wheels are to be replaced when
they exceed their life limit (transient speed excursions, hours, or cycles).
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 21 of 26 CAA of NZ
Compliance: By the 30 December 2006.
Effective Date: DCA/AL250/51 - 30 November 2006
DCA/AL250/51A - 26 July 2007
DCA/AL250/52 Generator Idler Gearshaft – Life Limit
Applicability: All model 250-C28 and 250-C30 series engines fitted with a generator idler gearshaft
P/N 6898980 or 6898591 or 77 tooth spur idler gearshaft P/N 6898652
These engines are known to be installed on, but not limited to Bell 206L-1 and
Sikorsky S-76 helicopters.
Requirement: To prevent failure of the accessory drive gearbox possibly resulting in loss of engine
power, the affected gearshaft must be removed from service prior to reaching the life
limit.
Accomplish these requirements per Commercial Engine Bulletins CEB 72-2003 for
250-C28 engines and CEB 72-3003 for 250-C30 series engines.
Note: For the purpose of this AD, a cycle is defined as an engine start, or an attempted
engine start, or the turning over of the engine using the starter. The start counter
which accumulates the cycle counts is only activated when the ignition circuit is
energized. A cycle must be added if the engine is turned over using the starter with
the ignition circuit off.
(FAA AD 79-16-06 refers)
Compliance: For 250-C28 series engines:
At 9000 CSN or within the next 50 cycles whichever is the later, unless previously
accomplished, and thereafter at intervals not to exceed 9000 cycles.
For 250-C30 series engines:
At 2000 CSN or within the next 50 cycles whichever is the later, unless previously
accomplished, and thereafter at intervals not to exceed 2000 cycles.
Effective Date: 26 June 2008
DCA/AL250/53 4th Stage Turbine Nozzles – Life Limit
Applicability: Model 250-C30, -C30P and C30S engines and turbine assemblies fitted with 4th stage
turbine nozzle assembly P/N 6898694,
Except model 250-C30 and 250-C30S engines with engine S/N, turbine S/N CAE
890690, 890691, CAT 95105, 95106, 890692, 890696 onward, 95108, 95109 onward,
and model 250-C30P engines, with engine S/N, turbine S/N CAE 895086, 895087
onward, CAT 95110, 95111, 95112 onward.
Requirement: To prevent cracks in 4th stage turbine wheel nozzles P/N 6898694 possibility resulting
in uncontained engine failure or loss of engine power or engine shutdown, accomplish
the following:
Inspect nozzles P/N 6898694, reduce the life limits based on inspection results and
replace affected nozzles in accordance with the schedule, instructions and inspection
criteria specified in Detroit Diesel Allison Commercial Engine Alert Bulletin CEB-A-72-
3056, revision 3 or later approved revision.
(FAA AD 81-13-12R1 refers)
Compliance: As prescribed in CEB-A-72-3056, unless already accomplished.
Effective Date: 26 June 2008
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 22 of 26 CAA of NZ
DCA/AL250/54 Turbine & Compressor Assemblies – Inspection
Applicability: Model 250-C30 engines, S/N CAE 900001 through to 9000026, and
Model 250-C30 and -C30S engines, S/N CAE 890001 through to 890840,
890843 through 890847, 890849 through to 890858, 890860, 890861, 890863, and
Model 250-C30R engines, S/N CAE 895068, 895077, 895078, 895082, 895084,
895085, 895096, and
Model 250-C30P engines, S/N CAE 895001 through to 895177, and
Fitted with turbine S/N CAT 900001 through to 90683, 95001 through to 95336, 95338
through to 95347, 95349, 95350, 95352 through to 95365, 95368, 95370, 95372
through to 95374, 95376 through to 95394, 95396, 95398 through to 95407
Except model 250-C30 series engines embodied with the following Allison
Commercial Engine Bulletins (CEB's):
Commercial Engine Bulletin No:
Subject:
CEB-A-72-3134, revision 2 dated 15 Sep
1985 or CEB-A-72-3135, revision 1 dated
15 Sept 1985 or later approved revision.
Engine, Turbine Assembly, Turbine-to-
Compressor Coupling Shaft-Replace.
CEB-72-3100, revision 1 dated 15 Sep
1985 or later approved revision.
Engine, Compressor Assembly, Spur
Adapter Gearshaft - modified by adding
Three Slots in Bore & Plugging Oil Feed
Hole.
CEB-72-3059, revision 4 dated 15 Sep
1985 or later approved revision.
Engine, Compressor and Gearbox
Assemblies - modify to Roller Number 2
1/2 Bearing Configuration.
CEB-72-3096, revision 1 dated 15 Sep
1985, or later approved revision
Engine, Turbine-Exhaust Collector
Modifications.
Requirement: To prevent cracks in the turbine-to-compressor coupling P/N 23008080, or carbon
build up on the turbine shafts and couplings that can cause shaft rub, or shaft
misalignment possibly resulting in a disconnect failure, engine overspeed and
uncontained engine failure, accomplish the following:
1. For model 250-C30 and -C30S engines fitted to Sikorsky S-76A aircraft:
1.1 Remove coupling P/N 23008080 and replace with P/N 23032345 in
accordance with Allison CEB-A-72-3134, revision 2, or later approved revision, or
as alternative temporary compliance, replace coupling P/N 23008080 with a
serviceable P/N 6896895 or P/N 6889071 per Allison CEB-A-72-3134.
1.2 Inspect, clean the turbine shafting/couplings and replace o-ring P/N AS
3085-018 (two for P/N 23032345 and one for P/N 6896895 or P/N 6889071) on
the aft end of the spur adapter gearshaft in accordance with CEB-A-72-3108,
revision 3 or later approved revision.
1.3 Modify the spur adapter gearshaft assembly P/N 23005276 per Allison
CEB 72-3100, revision 1 or later approved revision.
Modify the engine compressor and gearbox assemblies to include the roller
bearing configuration at the 2 1/2 bearing location per Allison CEB 72-3059,
revision 4 or later approved revision.
Replace turbine-to-compressor-couplings P/N 6896895 or P/N 6889071 with P/N
23032345 and install two o-rings P/N AS 3085-018 on the aft end of the spur
adapter gearshaft per Allison CEB-A-72-3134.
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 23 of 26 CAA of NZ
1.4 Modify the turbine-exhaust-collector per Allison CEB 72-3096, revision 1
or later approved revision.
2. For model 250-C30, -C30P, -C30R and -C30S engines fitted to another aircraft
other than a Sikorsky S-76A aircraft:
2.1 Inspect and clean the turbine shafting/couplings, and replace the o-rings
P/N AS 3085-018 (two for P/N 23032345 and one for P/N 6896895 or P/N
6889071) on the aft end of the spur adapter gearshaft per CEB-A-72-3143,
revision 2 or later approved revision.
2.2 Replace the turbine-to-compressor coupling P/N 23008080 with P/N
23032345 and fit two o-rings P/N AS 3085-018 on the aft end of the spur adapter
gearshaft per Allison CEB-A-72- 3135, revision 1 or later approved revision.
2.3 Modify the spur adapter gearshaft assembly P/N 23005276 per Allison
CEB 72-3100.
Modify the engine compressor and gearbox assemblies to include the roller
bearing configuration at the 2 1/2 bearing location per Allison CEB 72-3059,
revision 4 or later approved revision.
Replace turbine-to-compressor-couplings P/N 6896895 or P/N 6889071 with P/N
23032345 and install two o-rings P/N AS 3085-018 on the aft end of the spur
adapter gearshaft per Allison CEB-A-72-3135, revision 1 or later approved
revision.
2.4 Modify the turbine-exhaust-collector per Allison CEB 72-3096, revision 1
or later approved revision.
(FAA AD 84-24-54R2 refers)
Compliance: 1.1 Replace couplings P/N 23008080 before further flight, or accomplish alternative
temporary compliance per requirement 1 and replace coupling with P/N 23032345 at
the next turbine repair/overhaul shop visit, or within the next 12 months, whichever
occurs sooner.
1.2 & 2.1 Within the next 50 hours TIS, unless already accomplished within the
last 250 hours TIS, and thereafter at intervals not to exceed 300 hours TIS since the
last inspection.
1.3 & 2.3 At the next engine repair/overhaul shop visit, when both the compressor
and gearbox are disassembled to permit access, or within the next 12 months,
whichever occurs sooner.
1.4 & 2.4 At the next turbine repair/overhaul shop visit, or within the next 12
months, whichever occurs sooner
2.2 Within the next 100 hours TIS, or at next turbine repair/overhaul shop visit, or
within the next 2 months, whichever occurs sooner.
Effective Date: 26 June 2008
DCA/AL250/55 Outer Combustion Case Assembly – Inspection
Applicability: Model 250-C28 and -C30 series engines with an outer combustion case assembly P/N
6899237 or 23009569.
Requirement: To prevent cracks at the butt or seam weld on the outer combustion case P/N
6899237 and 23009569 progressing to a point where the case could rupture and
cause a sudden loss of engine power, accomplish the following:
1. For model 250-C28B, -C28C, -C30, -C30P, -C30R and -C30S engines:
1.1 With the aid of a bright light and a mirror, inspect all of the outer
combustion case welds which are located as follows:
a.) The horizontal butt welds on the outer surface and the welds
between the air discharge tube attachment flanges and gas producer
attachment flange on the forward side.
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 24 of 26 CAA of NZ
b.) Both forward and aft circumferential seam welds between the outer
case and inner liner.
c.) The welds attaching the bosses of fuel nozzle, both combustion case
drain valves and both igniter plugs.
If any cracks are found, the outer combustion case must be replaced
before further flight.
Note 1: Pay particular attention to welds in areas defined in sub-paragraphs a.)
where these horizontal welds meet the circumferential welds defined in
sub-paragraph b.)
Note 2: Requirement 1.1 of this AD may be accomplished by adding the
inspection requirement to the tech log. The visual inspection may be
performed and certified under the provision in Part 43 Appendix A.1 (7)
by the holder of a current pilot licence, if that person is rated on the
aircraft, appropriately trained and authorised (Part 43, Subpart B refers),
and the maintenance is recorded and certified as required by Part 43.
1.2 In addition to requirement 1.1 of this AD, inspect the areas of horizontal
butt weld between the air discharge tube attachment flanges and gas
producer attachment flange on the forward side of the outer combustion
case as follows:
a.) NDT inspect the designated areas using dye penetrant, or
b.) Apply a soap solution to the designated areas and with the aid of a
suitable power source turn the engine over to at least 20 percent N1, and
inspect for bubbles to reveal cracks.
If any cracks are found, the outer combustion case must be replaced
before further flight.
2. For model 250-C30 and -C30S engines fitted to Sikorsky Model S-76A
helicopters:
Replace or modify the outer combustion case assembly P/N 6899237 and
23009569 with/to P/N 23030910 and 23030911, respectively, per Allison CEB-A-
72-2113/3115 revision 2, or earlier/later approved revision.
3. For model 250-C28B, -C28C, -C30, -C30P, -C30R and -C30S engines fitted any
other aircraft other than a Sikorsky S-76A helicopter:
Replace or modify the outer combustion case assembly P/N 6899237 and
23009569 with/to P/Ns 23030910 and 23030911, respectively, per Allison CEB-
A-72-2113/3115.
(FAA AD 85-25-07R1 refers)
Compliance: 1.1 Before further flight and thereafter at every daily inspections until requirements 2
or 3 as applicable is accomplished.
1.2 Within the next 5 hours TIS, unless already accomplished within the last 20
hours TIS, and thereafter at intervals not to exceed 25 hours TIS from the last
inspection, until requirements 2 or 3, as applicable, is accomplished.
2. Within the next 150 hours TIS or within the next 6 months, whichever occurs
sooner.
3. At the next turbine repair or overhaul, or within the next 9 months, whichever
occurs sooner.
Effective Date: 26 June 2008
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 25 of 26 CAA of NZ
DCA/AL250/56 Compressor Mount Assembly – Inspection
Applicability: Model 250-C28B engines, S/N CAC 70011 through to 70793, 70795, and
Model 250-C28C engines, S/N CAC 28001 through to 28021, and
Model 250-C30, -C30P, -C30S engines, S/N CAC 90001 through to 90822, and
Fitted with compressor mount assembly P/N 6896021, 6898966 or 6898611.
Except model 250-C28 and -C30 series engines embodied with Allison Commercial
Engine Bulletin CEB 72-2085/3085, revision 1, or later approved revision.
Requirement: To prevent failure of the compressor mount that can cause misalignment and
subsequent failure of compressor to turbine shafting spline joints which may lead to
an inflight loss of power or disconnect of the gas producer turbine rotor with a
subsequent inflight shutdown/overspeed uncontained turbine wheel failure,
accomplish the following:
1. Inspect compressor mount assembly per the instructions of Allison CEB-A-72-
2080/3081, dated 15 September 1982 or later approved revision.
If only one crack is found in the compressor mount assembly and the crack has not
progressed beyond 3/8 inch of the edge of the mount sheet metal, the mount
assembly can remain in service provided that the inspections per requirement 1 of this
AD is accomplished at intervals not to exceed 25 hours TIS.
If one crack is found and the crack has progressed beyond 3/8 inch of the edge of the
mount sheet metal, or if more than one crack is found of any length, the compressor
mount assembly must be replaced before further flight.
2. Replace compressor mount assemblies P/N 6896021, 6898966 and 6898611
with P/N 23007217 per the instructions in Allison CEB 72-2085/3085, revision 1, dated
30 April 1985 or later approved revision.
(FAA AD 85-25-08 refers)
Compliance: 1. Within the next 100 hours TIS, unless already accomplished within the last 200
hours TIS, and thereafter at intervals not to exceed 300 hours TIS.
2. At the next compressor assembly overhaul or repair, or within the next 9 months,
whichever occurs sooner.
Effective Date: 26 June 2008
DCA/AL250/57 Cancelled – FAA AD 2015-02-22 refers
Effective Date: 09 March 2015
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Rolls-Royce 250 Series Turbine Engines
Issued 22 February 2018 Page 26 of 26 CAA of NZ
From 1 October 2012 the Civil Aviation Authority of New Zealand (CAA) will no longer rewrite the
text of State of Design ADs. Applicable State of Design ADs will be listed below and you can
obtain them directly from the National Airworthiness Authority (NAA) web sites. Links to the NAA
web sites are available on the CAA web site at
http://www.caa.govt.nz/airworthiness-directives/states-of-design/
If additional NZ ADs need to be issued when an unsafe condition is found to exist in an aircraft or
aeronautical product in NZ, they will be added to the list below.
* 2015-02-22 Cancelled – FAA AD 2017-18-14 refers
Effective Date: 13 October 2017
DCA/AL250/58 No. 5 Engine Bearing with P/N M250-10106 – Replacement
Applicability: All model 250 series engines fitted with a No. 5 bearing with P/N M250-10106.
Requirement: To prevent failure of the engine No. 5 bearing, which could result in loss of engine
power, replace the No. 5 bearing with a new part.
Accomplish the bearing replacement per the engine manufacturer instructions.
Note 1: Report any defects found to the CAA by completing a CA005 Defect Report form.
Provide photographs and as much engineering detail as possible, and also retain the
defective parts for analysis. The form can be obtained from
http://www.caa.govt.nz/Forms/CA005D_Form.pdf The completed form can be
emailed to the CAA at CA005@caa.govt.nz
Compliance: At 300 hours TTIS on bearing P/N M250-10106, or within the next 50 hours TIS,
whichever occurs later, and thereafter at intervals not to exceed 300 hours TIS.
Note 2: The installation of a No. 5 bearing with an alternate approved P/N is a terminating
action to the AD requirements.
Effective Date: 13 April 2016
* 2017-18-14 3rd and 4th Stage Turbine Wheels – Inspection
Applicability: Rolls-Royce Corporation (RRC) 250-C20, -C20B, -C20F, -C20J, -C20R, - C20R/1, -
C20R/2, -C20R/4, -C20W, -C300/A1 and -C300/B1 turboshaft engines fitted with
either a 3rd-stage turbine wheel P/N 23065818, or a 4th-stage turbine wheel P/N
23055944 or RR30000240.
Effective: 13 October 2017