Aerospace Engines A to Z
Aerospace Engines A to Z

Updated: 13-Feb-2020

"Etablissements Collet" in Gex, successfully built a fixed, three-cylinder, two-stroke radial engine.

-It had a displacement of 760 cc and gave 26/28 CV (28 CV maximum power and 26 CV power at cruise speed). This engine was named "Aviasport".

Collet - 3-cylinder radial engine
"Collet"

-It weighed 40 Kg. The ignition was by simple spark plug and a 'France' magneto. The compression ratio was 7 to 1. It had a 'Pilgrim' lubricating pump at adjustable flow.

Collet, side view
“Collet, side view” (Inverted photo)

-It was geared, so while the engine was rotating at 3,400 rpm, the propeller did it at 1,500 rpm.

From Appendix 10: The three-cylinder engine in the double photograph below belongs to the 28 hp Collet and not the 68 hp as titles the footer.

The Collet engine
"The Collet engine"

Engines of COLLET

Model: 3 cyl. radial, 26/28 HP

Arquitecture: 2-stroke3-cylinder Radial
Cooling:
Total Displacement: 760 cc
Bore / Stroke:
Power: 28 CV @ 3400 rpm
Weight: 40 Kg

Other details:

This engine was named "Aviasport".

Collet 3-cylinder radial engine

"Collet 3-cylinder radial engine"

The author of this edition of Aeroengines AtoZ, through Aeroteca, collaborated on Version 2 of this video, which is presented here.

To understand the operation of the connecting rods, the 1929 Continental R 670 single-cylinder engine was chosen.

A demonstration of Version 3, improved at the author's suggestion, is also available on YouTube at a later date. This version shows bronze valve guides, improved valve spring movement, and the split crankshaft counterweights and front bearing balls also move.

The design is from Juan Soler, Sant Cugat, Barcelona

Below we show a flash of version 3

Counting also with the coloboration of JMC of Enginys Mecanics in Mataro, Barcelona