Helice Normale propeller

[lion65]

Hello all forum members

Rare Helice Normale propeller from an Jero Farman HF.16 or HF.20 from the early Belgian Air Force about 1912-1914. Length 245 cm. These Farmans were built by the firm Bollekens in the area of Antwerp. Engine 80hp Gnome rotary. The propeller has a typical shape that holds the middle between a Ratmanoff and Chauviere design.
More information and photos on request.

Greetings from Holland,
Gert

[pmdec]

Hi Gert,

Interesting propeller... I hardly read the markings (perhaps KEY 30 7718 ) on your picture IMG_0507. Could you post a clear close-up of them? Are those markings on the intrados or the extrados (= are they visible on picture IMG_0505 or on IMG_0504)?
One more question about markings: they are often repeated at the root of one blade on Normale propellers. Is it the case?

And finally a "general" question: why do you think it is from a Farman?

Regards,
PM

[Dave]

Did you mean to post this in the "Selling" category?

If you, could you list the price, please?

[lion65]

Hello Dave,

the markings are: KCF 30 3718. (See enclosed better picture). I then had the luck two of these propellers to buy from an grandson of a old pilot of the Belgian Air Force. His grandfather flew the Farman Hf.16 and Hf.20. I've seen pictures of the plane with propeller. Sadly i have no copy, its is long ago. Enclosed another picture of an Belgian farman. The marking 'Helice Normale is visible at picture IMG_0504, i think it is 'extrados'. (pusher propeller). Only at one side.
It looks the propeller is shortened, but it isn't, this is the original length and shape.
Because i have two of them i want sell one. My asking price is 1750,- euro,
about 2330 American Dollar.

Greetings Gert

[pmdec]

Hi Gert,

Normale propellers and Ratmanoff are the same (Normale is the trademark of Ratmanoff props designed by Drzewiecki).
You are right, the prop is not shorten: serial KCF appears in a January 1914 Ratmanoff data sheet as being 2450 millimeters long (you sent me pictures of this KCF-30 prop in August 2010, but I had not the data sheet then).
Perhaps 2 of the 4 corners had been a little rounded (Ratmanoff props had quite square tips), but it is not annoying for a century old propeller. This serial (KCF) was made for 80HP Gnome engines rotating at 1200rpm. So, the Farman origin could be true, even if Ratmanoff data don't give a clue for that.

For my database, could you give the markings of your other one?

Your price seems very correct and I would be interested, but we already have one Ratmanoff of this era in very fine original condition.

Regards,
PM

[lion65]

Hi PM,
First the best wishes for 2013!
My other propeller is marked: KCF 34 - 3724. It has the original Helice Normale decals. The shape of the two propellers are exactly the same. I think they are not extra rounded. The lenght is a little longer 246 cm. Tomorrow i wil post some detail photo's.
Gretings Gert