Aerospace Engines A to Z
Aerospace Engines A to Z

Updated: 26-Apr-2026

One engine of this brand is a four-cylinder fan-shaped engine. There was also a three-cylinder, 25 HP fan-shaped (half-radial) version.

-It was installed on the Weiss monoplane with a tractor propeller. It would be replaced by a similar Anzani engine of the same power.

-A photograph of this air-cooled, four-cylinder fan-shaped engine has been located, with unit displacements of 90x120 mm.

Warren-Simpson and Co. Engine
“Warren-Simpson and Co. Engine”

-It produced 25 HP at 1,200 rpm and was presented at the 1910 Paris Motor Show.

From Appendix 9: Photograph of a fan-shaped engine of this brand, in the KJew Museum in France.

Warren Simpson with 4 cylinders
“Warren Simpson 4 cyl.” (AEHS)

-It's unusual for this type of engine to have 4 cylinders (even instead of odd). Two are noticeably advanced and the other two are further back, perhaps on a different crankshaft journal.

Engines of WARREN - SIMPSON

Model: 3 cyl. radial, 25 HP

Arquitecture:
Cooling:
Total Displacement:
Bore / Stroke: x
Power:
Weight:

Other details:
Model: 4 cyl. fan-shape

Arquitecture:
Cooling:
Total Displacement:
Bore / Stroke: x
Power:
Weight:

Other details:

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