# TCDS ATC 81: Textron Lycoming AVCO Corporation

- Type: Type certificate data sheet
- Status: Current
- Holder: Textron Lycoming AVCO Corporation
- Revision: 0
- Product: Engine
- Data sheet PDF: https://openairdocs.org/files/sha256/a1/9f/a19fd32f9bff1d58f22226779e2b363b2caf53c7a4f0aad4517aea0061dc067c
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/CF98B4180B8314428525670E004DE90F.0001
- Page: https://openairdocs.org/tcds/ATC%2081

## Models (3)

As the data sheet lists them.

- R-680-BA
- R-680-B2
- R-680-2

## What the data sheet says

This is OCR from the scanned FAA data sheet. OCR can misread letters and numbers.

```text
MODEIS: Avco LYcoming R-680-B2, -BA, -2
7.C. NUMBER: AIC 81
Model  R-680-B2, -BA, -2
lyre  9 RA
Rating:
Maximum continuous,
DE•  Ipm,  at S.L.
fress.  alt.  240-2000-S-I.
Iake-off, hr, rpm.
at full  throttle  240-2000
fuel (minimum octane
aviation gasoline)  80
Fore and stroke, in.  4_625 x 4_500
[ispiacement, cu. in.  680-4
Compression ratio  6-5;1
weight  (dry) ,  lbs.  473
Fropeller shaft,
SAE NO.  20
CarDuretion  stromberg NA-R7A carburetor with 2.0625 in. venturi
Ignition,  dual  Scintilla SC-A or SC-A2 magneto
Certification basis  Approved Type Certificate No. 81 (Expired 3/14/39)
The R-680-B2 model engine may be converted to the R-680-B5 by properly providing for use af a controllable
ritch propeller and by including the -B5 designation and ratings on the name plate.
```

## ADs (5, in force first)

- [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 95-26-02](https://openairdocs.org/ad/95-26-02): Aviation Gasoline · Lycoming Engines IO-320-B1A, IO-320-B1B, IO-320-B1C and 182 more. Effective Jan 24, 1996
- [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 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

## Registered aircraft by registry model (OpenAirDocs)

- [Lycoming R-680-2](https://openairdocs.org/engine/lycoming-r-680-2): 0 aircraft (registry code 42368)
- [Lycoming R-680-B2](https://openairdocs.org/engine/lycoming-r-680-b2): 0 aircraft (registry code 42366)
- [Lycoming R-680-BA](https://openairdocs.org/engine/lycoming-r-680-ba): 0 aircraft (registry code 42367)

## STCs approved under this data sheet (2)

- [STC SE04651CH](https://openairdocs.org/stc/SE04651CH): To allow use of l00R grade aviation fuel meeting Swift Fuel, LLC specification SPEC-l00R-22. Swift Fuels LLC
- [STC SE2413CE](https://openairdocs.org/stc/SE2413CE): Add the following approved fuel: unleaded automotive gas, 87 minimum antiknock index and leaded automotive gas, 88 minimum antiknock index, (RON+MON)/2.. Petersen Aviation Inc

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