Siemens propeller?

[capistro]

Hello dear friends. My boss got a two blade propeller from a friend. It is an wooden propeller with metal lining, six bolts and has the following markings:
80FS (or 80IS)
SIEMENS
D230
ST160
NI9802

Diameter is around 230 and ST is pitch. NI could be Neu Isenburg in Germany (that is were the gift came from) but I do not know.

It would make my day to be able to track any information about it.
Thanks / Michael

[Bob Gardner]

Grüße.

Willkommen zu unserem Forum.

I have been asked this question before and I have not yet come to a satisfactory answer. It is a prop for an 80ps Siemens engine. Theoretically this engine existed before WW1, c1912. But the high serial number of 9802 or 19802 suggests that it is post war.

The post war Siemens engine was a completely different engine from the pre-war one. I think it was a five cylinder radial and rotary design and hence called the Siemens Sternmotor (star) and rated at 110ps.

Mit freundlichen Grüßen,

Bob

[Bob Gardner]

More information.

Firstly, I sold a very similar prop to yours some years back with identical data but with the serial number 19790.

Secondly, the Deutsches Technikmuseum im Berlin has an early Siemens prop for a 100ps Siemens engine with St of 1600mm, same as yours, made by Behrend & Rüggebrecht who started making props around 1913 and do not seem to have made them later than 1916. This prop has the serial number of 12115. It is therefore possible that this 100ps engine is a develoment of your 80ps engine and that both props were made by Behrend & Rüggebrecht. They didn't make large numbers of props, so perhaps 19 indicates a prop type and 790 is the serial number and similarly 12115 on the DTMB prop is 12 115.

At the moment I think that your prop, the one I sold and the one at DTMB are all pre-WW1 props.

I do hope someone else comes up with something, so that I can tidy up my data!

MFG,

Bob

[capistro]

THANK YOU!

I really apprechiate this information. This prop is currently in the US and was a gift from an friend in Germany to him. I will give him the information.

Take care and fly safe.

/Michael

[Bob Gardner]

I'm glad that I was able to help. It looks like your boss has also asked us the same question. See the next post above yours.

Bob

[capistro]

That's correct and funny. Two souls - one thought. But I was a little bit quicker...

[Bob Gardner]

Isn't it better to be slower than your boss?

Bob