# Allison 250-C20R/1 - Type: Engine model (FAA registry) - Registry code: 03091 - Manufacturer (registry): ALLISON - Model: 250-C20R/1 - Engine type: Turbo-shaft - Power: 450 hp - Data sheet: [TCDS E4CE](https://openairdocs.org/tcds/E4CE) (OpenAirDocs) - Holder: Rolls-Royce Corporation - Installed in: 3 registered aircraft - Page: https://openairdocs.org/engine/allison-250-c20r-1 Model codes come from the FAA registry's reference file. ## ADs that may apply (OpenAirDocs) Matched to this engine model by model name and maker. Each AD's applicability may narrow it by serial number, part number or equipment. - [AD 2022-10-06](https://openairdocs.org/ad/2022-10-06): Turbine Section · Rolls-Royce 250-C20, 250-C20B, 250-C20C (T63-A-720) and 9 more. Effective Jun 28, 2022 - [AD 2018-13-01](https://openairdocs.org/ad/2018-13-01): Turbine Governor · Rolls-Royce 250-C10 (T63-A-5), 250-C18, 250-C18A and 24 more. Effective Aug 16, 2018 - [AD 2006-16-04](https://openairdocs.org/ad/2006-16-04): Inspection of the fuel nozzle screen · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 43 more. Effective Sep 7, 2006 - [AD 2006-13-06](https://openairdocs.org/ad/2006-13-06): Gas producer rotor assembly tie bolts · Rolls-Royce 250-B17, 250-B17B, 250-B17C and 16 more. Effective Jul 26, 2006 - [AD 2001-24-12](https://openairdocs.org/ad/2001-24-12): Helical Torquemeter Gearshaft Assembly · Rolls-Royce 250-B17, 250-B17C, 250-B17D and 13 more. Effective Dec 19, 2001 - [AD 98-24-28](https://openairdocs.org/ad/98-24-28): Main Fuel Control Bellows · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 36 more. Effective Jan 7, 1999 - [AD 96-19-01](https://openairdocs.org/ad/96-19-01): Superior Air Parts Manufacture Approval (PMA) Bearings · Rolls-Royce 250-B15G, 250-B17F, 250-B17F/1 and 17 more. Effective Sep 26, 1996 - [AD 88-17-01](https://openairdocs.org/ad/88-17-01): Fuel Controls · Rolls-Royce 250-B17, 250-B17B, 250-B17C and 26 more. Effective Mar 1, 1989 - [AD 82-24-05](https://openairdocs.org/ad/82-24-05): Control Assembly and Power Turbine Governor Assembly · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 43 more. Effective Nov 26, 1982 - [AD 77-15-12](https://openairdocs.org/ad/77-15-12): Power Turbine Coupling Nut · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 23 more. Effective Sep 23, 1977 Historical (superseded or no longer in force): - [AD 2017-18-14](https://openairdocs.org/ad/2017-18-14) (historical): Turbine Section · Rolls-Royce 250-C20, 250-C20B, 250-C20F and 8 more. Effective Oct 13, 2017 - [AD 2015-02-22](https://openairdocs.org/ad/2015-02-22) (historical): Repetitive visual inspections · Rolls-Royce 250-B17, 250-B17B, 250-B17C and 15 more. Effective Mar 9, 2015 - [AD 2004-24-09](https://openairdocs.org/ad/2004-24-09) (historical): Fuel nozzle · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 40 more. Effective Jan 5, 2005 - [AD 2001-20-51](https://openairdocs.org/ad/2001-20-51) (historical): Helical Torquemeter Gearshaft Assembly · 250-B17, 250-B17C, 250-B17D and 12 more ## Registered aircraft (3) - [N109ZT](https://openairdocs.org/aircraft/N109ZT): [Valiair Lc Trustee](https://openairdocs.org/faa-owner/VALIAIR%20LC%20TRUSTEE), [Casper, WY](https://openairdocs.org/faa-place/WY/Casper), built 1991, S/N 7639 - [N737PG](https://openairdocs.org/aircraft/N737PG): [Global Aircraft Trust Inc Trustee](https://openairdocs.org/faa-owner/GLOBAL%20AIRCRAFT%20TRUST%20INC%20TRUSTEE), [Cheyenne, WY](https://openairdocs.org/faa-place/WY/Cheyenne), built 1991, S/N 7659 - [N876VJ](https://openairdocs.org/aircraft/N876VJ): [Plane Fun Inc Tr Trustee](https://openairdocs.org/faa-owner/PLANE%20FUN%20INC%20TR%20TRUSTEE), [Snellville, GA](https://openairdocs.org/faa-place/GA/Snellville), built 1990, S/N 7634, Registration expired, pending cancellation ## NTSB investigations None matched to aircraft with this engine model. ## FAA accident and incident reports None matched to aircraft with this engine model. ## Service difficulty reports (13) As reported by operators and repair stations, by the model named in the report. - [SDR E7L2010F00000](https://openairdocs.org/sdr/E7L2010F00000), Jun 24, 2010: ENGINE. FLAMED OUT. ACFT HAD NR 2 ENGINE FLAME OUT. INSPECTED ACFT AND FOUND NO DISCREPANCIES. BLEED FUEL SYS. PERFORMED ENG POWER CK AND 20 MINUTE HOVER TEST FLIGHT WITH SATISFACT - [SDR 2009F00026](https://openairdocs.org/sdr/2009F00026), Apr 7, 2009: COMPRESSOR WHEEL. DAMAGED. PILOT REPORTED NR 1 ENG LOW WARNING LIGHT AND NR 1 ENG LOW AURAL ACTIVATED WITH CORRESPONDING DECREASE IN ENG SOUND. NR 1 ENG N1 WAS AT 28 PERCENT AND TOT WAS R - [SDR CA060214006](https://openairdocs.org/sdr/CA060214006), Feb 10, 2006: WASHER. MISSING. (CAN) AS ENG NR 2 WAS INCREASED, EXCEEDANCE ON INSTR PANEL, M/R READING HIGH ON TRIPLE TACH, NO INDICATION OF N2 SPEED ON TACH INDICATOR. FOUND N2 GOV GEAR FREE - [SDR AHE02062](https://openairdocs.org/sdr/AHE02062), Sep 4, 2002: CONNECTOR. DISCONNECTED. NR 1 ENGINE LOW WARNING ILLUMINATED IN FLIGHT. NG DROPPED AND FLICKERED BEFORE BECOMING ZERO. ENGINE RETARDED TO GROUND IDLE, ALL OTHER INDICATIONS NORMAL. AIRC - [SDR AU991049](https://openairdocs.org/sdr/AU991049), Oct 18, 1999: DIAPHRAGM. FAILED. (AUS) GAS PRODUCER TURBINE SECOND STAGE NOZZLE DIAPHRAGM FAILED AND RUBBING ON THE FIST AND SECOND STAGE TURBINE WHEELS. - [SDR CA990915038](https://openairdocs.org/sdr/CA990915038), Aug 27, 1999: IMPELLER. CRACKED. (CAN) ENGINE OIL COOLER/BLOWER ASSY DISASSEMBLED AT CUSTOMER'S REQUEST. IMPELLER WAS FOUND CRACKED (1/2) DURING FPI INSPECTION. MANUAL SPECIFIES THAT FPI IS CAR - [SDR AU990913](https://openairdocs.org/sdr/AU990913), Aug 11, 1999: ACTUATOR. CRACKED. (AUS) HYDRAULIC SERVO ACTUATOR LOCATED ON THE LEFT SIDE OF THE GEARBOX CRACKED ON THE UPPER BODY. LOSS OF NR 2 HYDRAULIC SYSTEM FLUID. - [SDR 99ZZZX2341](https://openairdocs.org/sdr/99ZZZX2341), May 27, 1999: NOZZLE. CRACKED. DIAPHRAGM CRACKED JUST UNDER INNER RIM, JUST OVER 2 INCHES LONG, AND LEFT VANE FILLET CRACKED AND BURNED. - [SDR 99ZZZX2342](https://openairdocs.org/sdr/99ZZZX2342), May 27, 1999: NOZZLE. CRACKED. INNER AND OUTER BAND CRACKS, SADDLE CRACKS, MANY VANE TRAILING EDGE CRACKS, MULTIPLE IN SAME VANE, SOME OVER .3750 INCH LONG. - [SDR 99ZZZX2343](https://openairdocs.org/sdr/99ZZZX2343), May 27, 1999: SHAFT. CORRODED. POWER TURBINE OUTER SHAFT HAS SEVERE DEEP CORROSION AT DIMPLES AND CURVIC COUPLING. CORROSION AT DIMPLES 360 DEGREES AROUND AND OVER HALF AS DEEP AS THE DIMPLE. - [SDR 99ZZZX2344](https://openairdocs.org/sdr/99ZZZX2344), May 27, 1999: SHAFT. CORRODED. POWER TURBINE OUTER SHAFT HAS SEVERE DEEP CORROSION AT DIMPLES AND CURVIC COUPLING. CORROSION AT DIMPLES 360 DEGREES AROUND AND OVER HALF AS DEEP AS THE DIMPLE. - [SDR 99ZZZX2349](https://openairdocs.org/sdr/99ZZZX2349), May 27, 1999: WHEEL. CRACKED. TURBINE WHEEL RIM CRACKED THROUGH KNIVES. - [SDR 99ZZZX2358](https://openairdocs.org/sdr/99ZZZX2358), Feb 1, 1999: BEARING. FAILED. PILOT FOUND GOVERNOR SWAGING ABOVE LIMITS FOR SAFE FLIGHT. ENIGNE SURGING 20 PSI TORQUE AND 5 PERCENT N2. UPON REMOVAL OF GOVERNOR, FOUND DRIVE SHAFT LOCKED-UP. ## STCs that may be installed (OpenAirDocs) (6) Approved for this engine model: the STC's model list names it on its data sheet, or a series that includes it. In force first, then newest. The registry doesn't record which STCs an aircraft has. - [STC SE5511NM](https://openairdocs.org/stc/SE5511NM): Installation of compressor discharge pressue (PC) valve. Bell Helicopter Textron Inc - [STC SE00014EN](https://openairdocs.org/stc/SE00014EN): Installation of the Pratt & Whitney Engine Services, Inc. CrossCheck Engine Monitor Kit P/N HUMS-K-071-1, Rev. A on the specified PT6A engine models and kit P/N HUMS-K-071-2 on the specified A250 engine models. Pratt & Whitney Engine Services Inc - [STC SE00027EN](https://openairdocs.org/stc/SE00027EN): Installation of Pratt & Whitney Engine Services Inc. Intellistart plus electronic control unit (ECU), P/N DPU-K-010 on the specified 250 engine models. Pratt & Whitney Engine Services Inc - [STC SE492GL](https://openairdocs.org/stc/SE492GL): Incorporation of a fuel flow transducer. Shadin Avionics - [STC ST00037AT](https://openairdocs.org/stc/ST00037AT): Unison igniter plugs, P/N 9044400-1. Unison Industries - [STC SQ00338AT](https://openairdocs.org/stc/SQ00338AT): Unison igniter leads, P/N9048222-101, 102, 103, 104, 105, 106. Unison Industries --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.