# TCDS ATC 20: Commonwealth Aircraft Inc.

- Type: Type certificate data sheet
- Status: Current
- Holder: Commonwealth Aircraft Inc.
- Revision: 0
- Product: Engine
- Data sheet PDF: https://openairdocs.org/files/sha256/8d/2e/8d2ede3444a3e1f5b65e74d206257aae487a15f2162653e9e7e2bdd85bcb552c
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/6480BDA3CE1401078525670B0066A86B.0001
- Page: https://openairdocs.org/tcds/ATC%2020

## Models (1)

As the data sheet lists them.

- LeBlond 90 7D

## What the data sheet says

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

```text
MODEIS: Commonwealth LeBlond 90 70
1.C. NUMBER: ATC 20
Model  LeBlond 90 7D
TRA
Iype
Rating:
Maximum continuous,
at SI.
press.  alt.  90-1975-S.1-
lake-off,
rEm. at full  throttle  90-1975
Fuel (minimum octane
Bore and stroke, in.  aviation gasoline)  4.125 × 3.750  70
Lisplacement, cu. in.  350-7
Compression ratio  5-35:1
Crankshaft  Weight (dry), lts.  gearing  Direct drive  291
Carburetion  Ignition,  Certification Lasis  dual  Approved Type Certificate No. 20  Stronterg NA-R3 carburetor  Scintilla MN7-D magnetos
NOIE 1-  AFfroval expired 12133 in certificated aircraft.  No engines of this model manufactured after this date or with serial numkers
7D-633 eligible for use
```

## ADs

None name its models.

## STCs approved under this data sheet (1)

- [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

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