# STC SE2352NM - Type: Supplemental type certificate - Status: Current, Reissued - Holder: Fifty-Ten-Yankee LLC, United States - Description: Modification of turbine engine. - Applied: April 29, 1981 - Status date: June 25, 2020 - Product: Engine - Certification basis: Part 13, Part 21, Part 33 - Data sheets: [TCDS E4CE](https://openairdocs.org/tcds/E4CE) - Certificate PDF: https://openairdocs.org/files/sha256/db/6a/db6adc4c0a50dc1e1fdd98df96550bd4da20159e784373eb01653c11f341ad4e - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/33A2B89BE13B4253862585DE003B8476.0001 - DRS record last changed: December 5, 2025 - Page: https://openairdocs.org/stc/SE2352NM ## ADs that name it (1) - [AD 93-25-05](https://openairdocs.org/ad/93-25-05): Driveshaft Flex Coupling Bolts, Bushings, and Nuts · Rolls-Royce 250-C20S with STC SE2352NM. Effective Feb 22, 1994. Named in the applicability ## Approved models (1) - Rolls-Royce Corporation 250-C20S ([TCDS E4CE](https://openairdocs.org/tcds/E4CE)) ## What the certificate says Read from the PDF's text layer, without the form's printed wording; the layout is lost and the order can differ. The PDF is the record. Number SE2352NM This certificate, issued to Fifty-Ten-Yankee, LLC 7600 Terminal Street SW Olympia, WA 98501 Part 13 of the Civil Air Regulations. Original ProductType Certificate Number: E4CE Make: Rolls-Royce Corporation Model: 250-C20S Description of the Type Design Change: Modification of Rolls-Royce Model 250-C20S turbine engine in accordance with Federal Aviation Administration (FAA) approved Fifty-Ten-Yankee, LLC Master Drawing List Number 780-100, Revision AS, dated March 28, 2020, or later FAA approved revisions. Limitations and Conditions: Approval of this change in type design applies to the basic Rolls-Royce Model 250-C20S engines which are otherwise unmodified. This approval should not be extended to other engines of this model that incorporate any other previously approved modifications unless it is determined that he interrelationship between this change and any other modifications will introduce no adverse effect on the airworthiness of these engines. A copy of this STC must be included with the permanent records of the modified engine. If the holder agrees to permit another person to use this certificate to alter the product, the holder shall give the other person written evidence of that permission. Date of application: April 29, 1981 Date reissued December 2, 2004; October 7, 2019; May 14, 2020; June 25, 2020 Date of issuance: May 2, 1984 Date amended December 17, 1982; February 22, 1985; April 23, 1986; May 11, 1992; December 2, 2004; March 22, 2005 FAA FORM 8110-2 (5/14) PAGE 1 OF 7 PAGES By direction of the Administrator (Signature) For Manager, Seattle ACO Branch (Title) Transfer the ownership of Supplemental Type Certificate Number to (Name of Transferee) (Address of Transferee) (Number and Street) (City, State, and ZIP Code) from (Name of Grantor) (Print or Type) (Address of Grantor) (Number and Street) (City, State, and ZIP Code) Signature of Grantor (In Ink): U.S. GPO: 1987-763-289 Number SE2352NM Fifty-Ten-Yankee, LLC Issued: May 2, 1984 Reissued: December 2, 2004; October 7, 2019; May 14, 2020; June 25, 2020 Amended: December 17, 1982; February 22, 1985; April 23, 1986; May 11, 1992; December 2, 2004; March 22, 2005 The Limitations and Conditions shown on Type Certificate Data Sheet Number E4CE for the Rolls -Royce Model 250-C20S engine remain applicable, except: Model: TURBINE PAC 780-1000-1 Type: Free Turbine Turboprop Axial Centrifugal Compressor Two-stage Gas Producer Two-stage Power Turbine Single Combustion Chamber Propeller Drive Ratio: - - - 3.323:1 Ratings: (See NOTE 3): Maximum Continuous: Shaft Horsepower - - - 398 hp Propeller Drive Speed - - - 1,180 rpm Torque Pressure - - - 96.4 psi Gas Producer Speed - - - 52,220 rpm Turbine Rotor Speed - - - 6,016 rpm Measured Gas Temperature - - - 1,434°F (779°C) Takeoff (5 minutes): Shaft Horsepower - - - 418 hp Propeller Drive Speed - - - 1,810 rpm Torque Pressure - - - 101.4 psi Gas Producer Speed - - - 53,000 rpm Turbine Rotor Speed - - - 6,016 rpm Measured Gas Temperature - - - 1,490°F (810°C) Principal Dimensions: Length overall, inches - - - 48.04 Width, inches - - - 29.70 Height, inches - - - 29.72 **FAA FORM 8110-2 (5/14) PAGE 3 OF 7 PAGES** United States of America Department of Transportation - Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number SE2352NM Fifty-Ten-Yankee, LLC Issued: May 2, 1984 Reissued: December 2, 2004; October 7, 2019; May 14, 2020; June 25, 2020 Amended: December 17, 1982; February 22, 1985; April 23, 1986; May 11, 1992; December 2, 2004; March 22, 2005 Center of Gravity (CG): CG location, aft of propeller flange face, inches - - - 22.10 CG location, below propeller axis, inches - - - 8.70 CG location, right of propeller axis, inches - - - 0.10 Weight: Basic turbine pac dry, lbs. - - - 317.3 Propeller Drive: Flanged, 4.250 inch bolt circle right holes, 0.594+ .005 inch diameter Fuel: Refer to Type Certification Data Sheet Number E4CE for fuels approved for the Allison 250-C20S engines. Oil: MIL-L-7808G or MIL-L-23699B and subsequent revisions thereto. Control System: Bendix Gas Producer Fuel Control - - - DP-P2 Bendix Power Turbine Governor - - - AL-AA1 (Turbine Overspeed Protection Only) Soloy Propeller Governor - - - 780-3356-3 Soloy Propeller Overspeed Governor - - - 780-3360-1 Certification Basis: Part 13 of the Civil Air Regulations (CAR’s), effective June 15, 1956, as amended by 13-1, 13-2, and 13-3, and exemption No. 219 from CAR 13.211, regulatory Docket 1337, dated August 6, 1962, and amended May 12, 1990, plus Section 33.4 of FAR Part 33, effective October 14, 1980. STC Application: STC application, dated April 29, 1981, amended December 17, 1982. **FAA FORM 8110-2 (5/14) PAGE 4 OF 7 PAGES** United States of America Department of Transportation - Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number SE2352NM Fifty-Ten-Yankee, LLC Issued: May 2, 1984 Reissued: December 2, 2004; October 7, 2019; May 14, 2020; June 25, 2020 Amended: December 17, 1982; February 22, 1985; April 23, 1986; May 11, 1992; December 2, 2004; March 22, 2005 Note 1: Maximum permissible temperatures: Measured gas temperatures: Takeoff power 1,490°F (810°C) Maximum continuous 1,434°F (779°C) Maximum transient (not to exceed six seconds) 1,490°F (810°C) 1,550°F (843°C) Starting 1,490°F (810°C) 1,700°F (927°C) Oil inlet temperatures: Maximum 225°F (93°C) Minimum MIL-L-7808G type oil - 65°F (-54°C) MIL-L-23699B type oil - 40°F (-40°C) Note 2: Fuel inlet and oil pressure limits: See Type Certification Data Sheet E4CE for Rolls-Royce 250-C20S engine. Note 3: Soloy Turbine PAC Rating and Conditions are as shown herein. Turbine PAC ratings, unless otherwise specified, are based on static sea level standard conditions with compressor inlet air (dry) 59°F, 29.92 in. hg., compressor inlet bell attached to provide suitable air approach conditions, no external accessory loads and no airbleed, and measured rated gas temperature as indicated by the average of the four gas temperature thermocouples. Note 4: The following accessory drive or mounting provisions are available: Driven by Gas *Direction Speed Ratio Max. Torque (lb. in.) Max. Overhung Producer Turbine of Rotation to Turbine Continuous Static Moment (in. lb.) Spare C 0.0728 35 75 30 Tachometer CC 0.0824 7 50 4 Starter-Generator C 0.2361 ** 550 94 **FAA FORM 8110-2 (5/14) PAGE 5 OF 7 PAGES** United States of America Department of Transportation - Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number SE2352NM Fifty-Ten-Yankee, LLC Issued: May 2, 1984 Reissued: December 2, 2004; October 7, 2019; May 14, 2020; June 25, 2020 Amended: December 17, 1982; February 22, 1985; April 23, 1986; May 11, 1992; December 2, 2004; March 22, 2005 Note 4: (Continued) Driven by Gas *Direction Speed Ratio Max. Torque (lb. in.) Max. Overhung Turbine Power of Rotation to Turbine Continuous Static Moment (in. lb.) Power Takeoff-rear C 0.1807 ***4,608 8000 700 Tachometer CC 0.1262 7 50 4 Driven by Power Speed Ratio Turbine off the *Direction to Prop Max. Torque (lb. in.) Max. Overhung Reduction Gearbox of Rotation * * * * Continuous Static Moment (in. lb.) Propeller Governor CC 1.4577 125 825 25 Propeller Overspeed Governor CC 1.821 100 800 25 Oil Pump CC 1.821 100 800 25 * C - Clockwise viewing drive pad CC - Counterclockwise ** The maximum generator load is 150 amperes (9.3 hp) *** The sum of the torque extracted in any combination from the front and rear power output drives shall not exceed the torque values specified in Note 7. **** Speed ratio to propeller based on propeller shaft speed of 1,810 RPM (100% N 2) Note 5: External air bleed may not exceed 4.5 percent. Note 6: Water injection operation is not approved. Note 7: The maximum allowable torque as measured by the torque meter for below st andard inlet air temperature and/or Ram conditions is 384 lb.–ft. for takeoff and 349 lb.–ft. for maximum continuous operations. Note 8: Maximum shaft speeds for momentary transients (up to 15 seconds) and for sustained operation: Transient Sustained Propeller Shaft 110% 105% Power Turbine 110% 105% Gas Producer 106% 105% 100% propeller speed is defined as 1,810 RPM 100% power turbine speed is defined as 6,016 RPM 100% gas producer is defined as 50,970 RPM (See Continuation Sheet Page 7 of 7 Pages) FAA FORM 8110-2 (5/14) PAGE 6 OF 7 PAGES Number SE2352NM Fifty-Ten-Yankee, LLC Issued: May 2, 1984 Reissued: December 2, 2004; October 7, 2019; May 14, 2020; June 25, 2020 Amended: December 17, 1982; February 22, 1985; April 23, 1986; May 11, 1992; December 2, 2004; March 22, 2005 Note 9: The turbine Pac Model 780-1000-1 is eligible for tractor applications only utilizing three-bladed propellers. Note 10: The turbine PAC Model 780-1000-1 has not been shown to meet FAA requirements for operation in icing conditions Note 11: Life limits established for the Turbine Pac Model 780-1000-1 engine are published in the Soloy Turbine Pac Maintenance and Overhaul Manual. Note 12: Life limits established for the Rolls-Royce Model 250-C20S engine are published in the Rolls-Royce Gas Turbine Operation and Maintenance Manual. Note 13: Installation requirements for the Turbine Pac Model 780-1000-1 are included in the Soloy Turbine Pac Installation Design Manual. - END - **FAA FORM 8110-2 (5/14) PAGE 7 OF 7 PAGES** ## Every issue (2) - June 25, 2020: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/db/6a/db6adc4c0a50dc1e1fdd98df96550bd4da20159e784373eb01653c11f341ad4e) - March 22, 2005: Amended, Historical. [certificate](https://openairdocs.org/files/sha256/3e/d6/3ed62fcb7314df19ccacaec36d804565197975938ceb64599fe813385aa04c55) --- 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.