Aerospace Engines A to Z
Aerospace Engines A to Z

Updated: 22-May-2019

HOFFMANN - ROTOR

(Germany)


HOFFMANN - ROTOR engine specifications

Hoffman Rotor made a 7-cylinder rotary radial that gave 60 hp. It was installed on the Sommer monoplane, made by Deutsche Sommer Flugzeugwerke.

Foto del Sommer con su motor Hoffmann
“Picture of the Sommer with its Hoffmann engine” (PeT)

From Appendix 10: We have located an engine of this brand on the Deutsche Sommer monoplane aircraft. Of 60 CV and the year 1911.

The Deutsche Sommer with the rotary engine
“The Deutsche Sommer with the rotary engine”

-The Hoffmann-Rotor is a 7-cylinder rotary engine.

-In the text appears the same photo in negative for not having authorization. Now we have it from another source.

Enlargement to discover the Hoffmann-Rotor rotary engine
"Enlargement to discover the rotary engine"

From Appendix 12: Through a German publication, now we have a picture of the engine on the airplane that appears in the main text. This 7-cylinder engine was designed by George Hoffmann and gave 60 CV.

George Hoffmann y su motor
“George Hoffmann and his engine” (PiP-Flu)

Engines of HOFFMANN - ROTOR

Model: 7 cyl. rotary radial 60 CV

Arquitecture: 7-cylinder Rotary
Cooling:
Total Displacement:
Bore / Stroke:
Power: 60 CV
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