# TCDS E-279: Lycoming Engines

- Type: Type certificate data sheet
- Status: Current
- Holder: Lycoming Engines
- Revision: 10
- Revised: November 4, 2010
- Product: Engine
- Registered aircraft: 215, by the registry models matched to it (OpenAirDocs)
- Data sheet PDF: https://openairdocs.org/files/sha256/50/2e/502e6f784d0c43acf97504db585f6c71a22910cdb401bf7c8786841802be6b79
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/AD3F762C953C59408625780E005C84A1.0001
- Page: https://openairdocs.org/tcds/E-279

## Models (7)

As the data sheet lists them.

- VO-435-A1A (O-435-21)
- VO-435-A1F
- VO-435-A1C (O-435-23; -23A; -23B; -23C)
- VO-435-A1E
- VO-435-A1D (O-435-6A)
- VO-435-B1A
- VO-435-A1B (O-435-6)

## What the data sheet says

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

```text
DEPARTMENT OF TRANSPORTATION 
FEDERAL AVIATION ADMINISTRATION 
E-279 
Revision 10 
Lycoming Engines 
(O-435-21) VO-435-A1A 
(O-435-6) VO-435-A1B 
(O-435-23; -23A, -23B, 23C) VO-435-A1C 
(O-435-6A) VO-435-A1D 
VO-435-A1E, -A1F 
VO-435-B1A 
 
November 04, 2010 
 
TYPE CERTIFICATE DATA SHEET NO. E-279 
 
Engines of models described herein conforming with this data sheet (which is a part of type certificate No. 279) and other approved 
data on file with the Federal Aviation Administration meet the minimum standards for use in certificated aircraft in accordance with 
pertinent aircraft data sheets and applicable portions of the Civil Air Regulations/Federal Aviation 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, Av co Corp. Williamsport PA transferred TC E-279 to Lycoming 
Engines, An Operating Division of AVCO Corporation on November 04, 2010 
 
Model         Lycoming VO-435 -A1A  -A1B, -A1C, -A1D -A1E -A1F -B1A 
Type 6H0A Vertical Mounting    
  Direct Drive  
     
Rating      
  Maximum continuous, hp., r.p.m,       
    full throttle, at:      
    Sea level pressure altitude  
      (ft.) 
250-3200-S.L. - - - - - - 265-3200-S.L. 
  Takeoff (5 min.), hp., r.p.m.,      
    full throttle, at:      
    Sea level pressure altitude 260-3400-S.L. - - - - - - 265-3200-S.L. 
Fuel (Minimum grade aviation  
  gasoline) 
80/87 - - - - - - 100/130 
Bore and stroke, in. 4.875 x 3.875 - - - - - - - - 
Displacement, cu. in. 434 - - - - - - - - 
Compression ratio 7.3:1 - - - - - - 8.7:1 
Weight (dry), lb. See NOTE 6 - - - - - - - - 
C.G. location (dry & in  
  horizontal position) 
     
  From front face of crankcase,  
    in. 
15.50 15.30 14.95 - - - - 15.39 
  Off propeller shaft C.L., in. 0.15 above 
& 0.25 left 
0.14 
above 
& 0.24 
left  
(-A1B 
& 
-A1D) 
0.07 
above 
& 0.26 
left  
(-A1C) 
- - - - 0.37 below & 
0.18 left 
Propeller shaft Flange type 
power takeoff 
- - - - - - - -

Model         Lycoming VO-435 -A1A  -A1B, -A1C, -A1D -A1E -A1F -B1A 
Carburetion * MA4-5 or 
MA4-5AA 
- - MA4-5AA - - - - 
Ignition dual S6RN-20, -21 
magnetos 
S6RN-21, 
S6LN-20 
S6LN-204, 
S6RN-200 
- - S6LN-1208, 
S6RN-1209 
Timing, °BTC 25 - - - - - - - - 
Spark plugs See NOTE 5 - - - - - - - - 
Oil sump capacity, qt. Dry sump - - - - - - 10 
Usable oil, qt. (15° nose up or  
  down) 
    6 
 
NOTES 
 
1,2,3,4,5,6,7,9 
 
- - 
 
1,2,3,4,5,6,9 
 
1,2,3,4,5,6, 
8,9 
 
- - 
"- -" indicates "same as preceding model" 
"" indicates "does not apply" 
* See latest edition of Lycoming SI 1523 for alternate approved Carburetors 
 
Certification basis:  
 
Regulations and Amendments 
 
Model 
 
Date of Application 
Date Type Certificate  
No. 279 Issued/Revised 
CAR 13 Effective March 5, 1952    
As Amended By 13-1 VO-435 Ma rch 10, 1954 October 11, 1954 
 VO-435-A1A (VO-435 Redesi gnated) October 29, 1954 
13-2 VO-435-A1B May 13, 1955 June 10, 1955 
 VO-435-A1C July 14, 1955 July 18, 1955 
CAR 13 Effective June 15, 1956 VO-435- A1D August 9, 1956 September 27, 1956 
As Amended By 13-1, 13-2 VO-435-A1 E September 18, 1959 October 15, 1959 
13-3 VO-435-A1F January 25, 1961 March 6, 1961 
 VO-435-B1A August 10, 1965 December 15, 1965 
Production basis: Production Certificate No. 3 
 
NOTE 1. Maximum permissible temperatures: 
Cylinder Head 
(Well Type) 
 
Cylinder Base 
 
Oil Inlet 
 (See Note 8)  
500°F 325°F -A1A, -A1B 225°F 
 350°F -A1C, -A1D, -A1E 235°F, -A1F, -B1A 
 
NOTE 2.    Minimum  Maximum  
 Fuel Pressure Limits  0.5 p.s.i.  8 p.s.i. 
 Oil Pressure Limits (Normal Operation) 65 p.s.i. 85 p.s.i. 
   (Idling 25 p.s.i) 
 
NOTE 3. The following accessory provisions are incorporated: 
  -A1B   Direction   Maximum 
  -A1D   of Speed X Maximum Torque Overhang 
  -A1E   Rotation Crankshaft in. -lb. Moment 
Accessory -A1A -A1F -A1C -B1A Faci ng Pad r.p.m. Cont. Static in. - lb. 
          
Starter-Electric  X X X X C 1.000:1  12000 300 
Starter-Manual X X X  C 2.600:1  2200  
Alternator    X CC 2.250:1 60 400 175 
*Generator X X X  C 2.600:1 500 2200 400 
**Fuel Pump X X X  CC .803:1 25 450 25 
Vacuum Pump    X C 1.105:1 200 800 25 
Vacuum Pump X X X  C 1.219:1 200 800 25 
Hydraulic Pump    X C 1.105:1 400 1650 175 
Hydraulic Pump X  X  C 1.083:1 400 1650 175 
Tachometer X X X  CC .500:1 7 50  
Tachometer    X CC .500:1 7 50 5 
* Inoperative as generator drive when fitted with hand crank jaw. 
** Accessory housing machined for drive but drive not supplied as standard on -A1A, -A1B, -A1D, -A1E; -B1A has no provisions 
for fuel pump drive.

C-Clockwise, CC-Counter Clockwise, X-Standard 
 
NOTE 4. The VO-435 series engines are specially a pproved for helicopter applicants and operation. 
 
NOTE 5. Spark plugs approved for use on these engines are listed in the latest revision of Lycoming Service Instruction No. 1042. 
 
NOTE 6. The above models incorporate additional characteristics as follows: 
 
 VO-435 Models  Weight (lb.)  Characteristics  
 
 VO-435-A1A 396  Basic Model.  Six cylinder air c ooled, horizontally opposed, vertical direct drive 
dry sump engine with side mounted AN type accessory drives. 
 
 VO-435-A1B 391  Same as VO-435-A1A except for a modified accessory section. 
 
 VO-435-A1C 399  Same as VO-435-A1B for crank case and oil sump modification to provide 
increased strength and incorporate an oil pump housing which is machined for a 
hydraulic pump drive. 
 
 VO-435-A1D 390  Same as VO-435-A1B except for cra nkcase and oil sump modifications to provide 
increased strength. 
 
 VO-435-A1E 392  Same as VO-435-A1D except for S6RN-200 and S6LN-204 magnetos. 
 
 VO-435-A1F 399  Same as VO-435-A1E except has inte rnal piston cooling oil jets and heavy duty 
cylinders.  Convertible to TVO-435-A1A. 
 
 VO-435-B1A 419  Differs from VO-435-A1F by incorporation of a redesigned accessory drive 
section with wet oil sump and a higher compression ratio of 8.7:1. 
 
NOTE 7. The following military and civil engine models are equivalent: 
  VO-435-A1A - O-435-21 
  VO-435-A1B - O-435-6 
  VO-435-A1C - O-435-23, -23A, -23B, -23C 
  VO-435-A1D - O-435-6A 
 
  When installed in certificated aircraft, the corresponding civil model designation and type certificate number should be 
added to the engine data plate. 
 
NOTE 8. Cylinder base temperature limits are not applicable to e ngine models which incorporate internal piston cooling oil jets. 
 
NOTE 9. Starters, generators and alternat ors approved for use on these engines are listed in the latest revision of Lycoming 
Service Instruction No. 1154. 
 
- END -
```

## ADs (10, 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 2022-16-03](https://openairdocs.org/ad/2022-16-03): Engine (RECIPROCATING) · Continental Aerospace Technologies GTSIO-520-C, GTSIO-520-D, GTSIO-520-F and 236 more. Effective Aug 15, 2022
- [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 90-04-06 R1](https://openairdocs.org/ad/90-04-06-R1): Propeller Governor External Oil Line · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 427 more. Effective May 28, 1991
- [AD 80-04-04 R1](https://openairdocs.org/ad/80-04-04-R1): Crankshaft Flange Bolts · Lycoming Engines IVO-540-A1A, TIVO-540-A2A, TVO-435-A1A and 38 more. Effective Aug 18, 1980
- [AD 69-24-03](https://openairdocs.org/ad/69-24-03): Carburetors · Continental Motors A-65-1, A-65-12, A-65-12F and 321 more. Effective Nov 29, 1969
- [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 68-08-08](https://openairdocs.org/ad/68-08-08): Hydraulic Valve · Lycoming Engines IGSO-480-A1A6, IGSO-480-A1B6, IGSO-480-A1C6 and 44 more. Effective May 19, 1968
- [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 VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series): 191 aircraft (registry code 41525)
- [Lycoming VO-435-A1F](https://openairdocs.org/engine/lycoming-vo-435-a1f): 15 aircraft (registry code 42200)
- [Lycoming VO-435-B1A](https://openairdocs.org/engine/lycoming-vo-435-b1a): 6 aircraft (registry code 42201)
- [Lycoming VO-435-A1D](https://openairdocs.org/engine/lycoming-vo-435-a1d): 3 aircraft (registry code 42198)
- [Lycoming VO-435-A1A](https://openairdocs.org/engine/lycoming-vo-435-a1a): 0 aircraft (registry code 42195)
- [Lycoming VO-435-A1B](https://openairdocs.org/engine/lycoming-vo-435-a1b): 0 aircraft (registry code 42196)
- [Lycoming VO-435-A1C](https://openairdocs.org/engine/lycoming-vo-435-a1c): 0 aircraft (registry code 42197)
- [Lycoming VO-435-A1E](https://openairdocs.org/engine/lycoming-vo-435-a1e): 0 aircraft (registry code 42199)

## STCs approved under this data sheet (25)

- [STC SE2932SW](https://openairdocs.org/stc/SE2932SW): Install carburetor air temperature indicator. Approved for Aircooled Motors (Franklin Engine Co.) equipped with float carburetors. Model eligibility included here may not be inclusive.. Alcor LLC
- [STC SE01954SE](https://openairdocs.org/stc/SE01954SE): Installation of engine crankcase seal.. Ly-Con Rebuilding Company
- [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 SE8628SW](https://openairdocs.org/stc/SE8628SW): Installation of oil nozzles for lubrication of cam and filters.. Cygnet Aerospace Corp
- [STC SE4408SW](https://openairdocs.org/stc/SE4408SW): Miscellaneous engine cylinder replacement parts.. Continental Motors, Inc.
- [STC SE7504SW](https://openairdocs.org/stc/SE7504SW): Installation of any or all parts listed on Airmotive Engineering Drawing List No. 852-1, Rev. 1, dated 10/4/88, or later FAA approved revision.. Continental Motors, Inc.
- [STC SE7665SW](https://openairdocs.org/stc/SE7665SW): Installation of parts listed on Airmotive List No. 8810-3, Rev 6.. Continental Motors, Inc.
- [STC SE8776SW](https://openairdocs.org/stc/SE8776SW): Installation of coated cylinders and piston rings.. Continental Motors, Inc.
- [STC SE2902NM](https://openairdocs.org/stc/SE2902NM): Lycoming valve cover gasket. Real Gaskets Tennessee
- [STC SE144GL](https://openairdocs.org/stc/SE144GL): Modify engine to increase compression ratio to 8.7:1.. Scott's Bell 47 Inc
- [STC SE2500SW](https://openairdocs.org/stc/SE2500SW): Modification to higher compression ratio.. Scott's Bell 47 Inc
- [STC SE2733SW](https://openairdocs.org/stc/SE2733SW): Modification to higher compression ratio.. Scott's Bell 47 Inc
- [STC SE1-201](https://openairdocs.org/stc/SE1-201): Installation of the Richter Aero Equipment Type B-4 or B-5 Temperature Probe. (O-360 SERIES (excl. A1C, C2B, C2D)). MidContinent Instru Co 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 SE00350SE](https://openairdocs.org/stc/SE00350SE): Installation of sump mounted chip detector.. Aviation Development Corporation
- [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 SE5879SW](https://openairdocs.org/stc/SE5879SW): Use of Phillips X/C II 20W-50 and25W-60 oil (OSS 55875) in all Avco reciprocating aircraft engines from 65 to 450 BHP.. Phillips Petroleum Co
- [STC SE5924SW](https://openairdocs.org/stc/SE5924SW): Installation of stainless steel replacement exhaust studs on AVCO engines.. Perrigo & Steele Aircraft Engr Company
- [STC SE80NE](https://openairdocs.org/stc/SE80NE): Installation and usage of Bel-Ray synthetic aviation oil, Bel-Ray Aero 1, (nonsupercharged), horizontally opposed direct drive, aircraft engines of 350 hp. or less.. Bel-Ray Company, Inc
- [STC SE1445SO](https://openairdocs.org/stc/SE1445SO): Use of Aero-blend oil additive in Teledyne (non turbocharged) aircraft engines.. ProTec
- [STC SE128NE](https://openairdocs.org/stc/SE128NE): Use of AMS/OIL 15W 50 synthetic piston aircraft oil in Avco engines.. AMS/OIL
- [STC SE959EA](https://openairdocs.org/stc/SE959EA): Modification to higher compression ration.. Agrotors, Inc
- [STC SE2-856](https://openairdocs.org/stc/SE2-856): American Bosch Induction vibrator VJR24B56X.. Bell Helicopter Textron
- [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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