# TCDS E-285: Lycoming Engines

- Type: Type certificate data sheet
- Status: Current
- Holder: Lycoming Engines
- Revision: 3
- Revised: November 4, 2010
- Product: Engine
- Data sheet PDF: https://openairdocs.org/files/sha256/8f/99/8f9906864aa2ac66e051987680dacba65fd11f90b62d504a7e91a5b3f622590a
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/BBD44B1D3C05B36F8625780E005CD11A.0001
- Page: https://openairdocs.org/tcds/E-285

## Models (3)

As the data sheet lists them.

- SO-580-A1B
- SO-580-A1A
- VSO-580-A1A

## What the data sheet says

From the PDF's text layer, line by line; tables lose their columns. The PDF is the record.

```text
Page No. 1 2 
Rev. No. 3 2 
 
FEDERAL AVIATION AGENCY 
 
E-285 
Revision 3 
LYCOMING Engines 
 SO-580-A1A 
 SO-580-A1B 
 VSO-580-A1A 
November 04, 2010 
 
AIRCRAFT ENGINE SPECIFICATION 
 
Engines of models described herein conforming with this specification and approved data on file with the Federal Aviation 
Agency, meet the minimum standards for use in certificated aircraft in accordance with pertinent aircraft specifications and 
applicable portions of the Civil Air Regulations provided they are installed, operated, and maintained as prescribed by the 
approved manufacturer’s manuals and other approved instructions. 
 
Type Certificate Holder Lycoming Engines 
 An Operating Division of AVCO Corporation 
 Williamsport, Pennsylvania 17701 
 
Type Certificate Holder Record Avco Lycoming Division, Avco Corp. transferred TC E-285 to Lycoming Engines, An 
Operating Division of AVCO Corporation on November 04, 2010 
 
Model  Lycoming    SO-580-A1A, -A1B; VSO-580-A1A  
 
Type  8HOA - Direct Drive 
Rating 
 Max. continuous, hp, rpm, in. Hg., at: 
  Rated press. alt. (ft.)     350-3000-36.2-6000 
  Sea level press. alt. (ft.)     350-3000-37.5-S.L. 
 Takeoff (5 min.), hp, rpm, in. Hg., at: 
  Rated press. alt. (ft.)     400-3300-40.8-4200 
  Sea level press. alt. (ft.)     400-3300-41.5-S.L. 
Fuel (Min. grade aviation gasoline)    100/130 
Lubricating Oil      MIL-L-6082  
         Latest Edition of Lycoming Service Instruction No. 1014 
Bore and stroke, in.      4.875 x 3.875 
Displacement, Cu. In.     578 
Supercharging ratio      7.91:1 
Compression ratio      7.30:1 
Weight (dry) lbs.      See NOTE 4 
C. G. location (dry)      See NOTE 4 
Propeller shaft      Flanged type power takeoff 
Carburetion      PAC+ PS9BDE 
Ignition Dual      See NOTE 4 
Timing, B T C       2 5  
Spark plugs      See NOTE 7 
Oil Sump - capacity     Dry Sump 
NOTES       1,2,3,4,5,6,7 
 
“_ _”  indicates “same as preceding model” 
+ PAC formerly Bendix 
 
Certification basis  Type Certificate No. 285 
 
Production basis  Production Certificate No. 3

E-285 2 
NOTE 1.  Maximum permissible temperatures: 
Cylinder Head   
(Well type) Cylinder Base  Oil Inlet  
475F 325 F 225 F 
 
NOTE 2. 
 Min.  Max..  
Fuel Pressure Limits 9 psi 15 psi 
Oil Pressure Limits (Normal Operation) 65 psi 85 psi 
  (Idling) 25 psi  
 
NOTE 3.  The following accessory provisions are provided: 
 
  Speed X Maximum Torque  
 Direction of Rotation Cranksha ft (in.-lb.) Maximum Overhang 
Accessory Facing Engine Pad  RPM  Cont.  Static  Moment (in.-lb.)  
Starter C 1.000:1 - 12000 300 
Generator C 2.600:1 500 2200 400 
Fuel Pump CC .803:1 25 150 25 
Vac. Pump C 1.219:1 200 800 25 
Hyd. Pump C 1.083:1 300 1650 75 
Tachometer CC .50:1 7 50 - 
 
NOTE 4. 
 SO-580-A1A  SO-580-A1B  VSO-580-A1A  
Engine Dry Weight (lbs) 596 578 592 
 
Center of Gravity Position    
Off Propeller Shaft C.L., in. .67 Above & .52 Above & .31 Below & 
 .10 Right .10 Right .10 Right 
    
From Front Face of crankcase, in. 20.7 20.4 21.65 
 
Ignition - Dual (4 Mags.) (2) S4LN-50 (2) S4LN-20 (2) S4LN-20 
 (2) S4LN-51 (2) S4LN-21 (2) S4LN-21 
 
NOTE 5.  These engines are approved for helicopter  application and operation.  The SO-580-A1A and 
   A1B engines are designed for installation in  a horizontal position or up to 35 nose up attitude. 
   The VSO-580-A1A is intended for vertical installation. 
 
NOTE 6.  The SO-580-A1A and A1B are furnished with a flange power takeoff at the front end of the 
   crank shaft.  An oil seal or closure suitabl e to the requirements of the helicopter transmission 
   system must be provided by the helicopter  manufacturer.  Doman Helicopters Inc. Kit No. 15001 
   is one approved arrangement. 
 
NOTE 7.  The following spark plugs are approved on these engines: 
 
   AC  S-86R, SR-83P, HSR-83P 
   Autolite  SH-2M, SH-20, SH-20A 
   RG  RB485S 
   Champion R25S, RED37N, REM37N 
     RHD37N, RHM37N 
 
 
 
...END...
```

## ADs (5, in force first)

- [AD 2026-04-11](https://openairdocs.org/ad/2026-04-11): Engine (Reciprocating) · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 605 more. Effective Apr 8, 2026
- [AD 2012-03-07](https://openairdocs.org/ad/2012-03-07): Carburetor · Lycoming Engines GO-435, GO-435-C2 (O-435-17), GO-435-C2A and 389 more. Effective Mar 27, 2012
- [AD 2004-10-14](https://openairdocs.org/ad/2004-10-14): Crankshaft gear · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 642 more. Effective Jun 25, 2004
- [AD 66-06-03](https://openairdocs.org/ad/66-06-03): Connecting Rod Assemblies · Lycoming Engines GO-435-C2 (O-435-17), GO-435-C2A, GO-435-C2A2 and 317 more. Effective Jan 16, 1969
- [AD 2024-21-02](https://openairdocs.org/ad/2024-21-02) (historical): Engine (Reciprocating) · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 548 more. Effective Dec 5, 2024

## Registered aircraft by registry model (OpenAirDocs)

- [Lycoming SO-580-A1A](https://openairdocs.org/engine/lycoming-so-580-a1a): 0 aircraft (registry code 42225)
- [Lycoming SO-580-A1B](https://openairdocs.org/engine/lycoming-so-580-a1b): 0 aircraft (registry code 42226)
- [Lycoming VSO-580-A1A](https://openairdocs.org/engine/lycoming-vso-580-a1a): 0 aircraft (registry code 42227)

## STCs approved under this data sheet (7)

- [STC SE01966WI](https://openairdocs.org/stc/SE01966WI): Use of GAMI G100UL High Octane Unleaded Avgas in spark ignition piston aircraft engines. General Aviation Modifications Inc.
- [STC SE1779NM](https://openairdocs.org/stc/SE1779NM): Installation of Precise Flight, Inc. Standby Vacuum System SVS III. Precise Flight Inc
- [STC SE09492SC](https://openairdocs.org/stc/SE09492SC): Installation and usage of Exxon 20W50 multigrade aircraft engine oil conforming to Exxon Oil formulation WS-3013.. Exxon Company USA
- [STC SE8023SW](https://openairdocs.org/stc/SE8023SW): Installation and usage of AEROSHELL. Shell Development Co
- [STC SE452NE](https://openairdocs.org/stc/SE452NE): Installation and usage of 'Mobil AV 1' aviation oil.. Mobil Research & Development Corp
- [STC SE128NE](https://openairdocs.org/stc/SE128NE): Use of AMS/OIL 15W 50 synthetic piston aircraft oil in Avco engines.. AMS/OIL
- [STC SE44WE](https://openairdocs.org/stc/SE44WE): Use of Kling Aviation Oil, Specifications KL-100, KL-200 and KL-300 in Continental and Lycoming engines.. Kling Oil Company

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