Barn find propeller

[Oceandriver]

I have recently become the caretaker of this old (modern?) prop and would like to find out as much about it as you clever people can tell me!
The overall length of the propeller is 200cms. It is sheathed on the leading edges in copper or bronze metal.
From the markings, and my own research, I've been led to think it is a French model, but not necessarily constructed in France. The 18 cv, relates to cheveaux or horsepower which is not much in flying terms. The "AZ" may be Anzani engine. The use of the word Hydro suggests water, perhaps an early hydrofoil, and the word Galvin could link it to a Clement Galvin who was involved in a "floatplane" development that was tested in 1919, but never went into production.
Series number and model number are clearly visible. Is the number a date? 30th April 1911?
It is in the condition I got it in, and I have done nothing other than expose markings by wiping dust and spider poo away with a dry cloth!
Any clues on this or any indication of potential value would be great as I'd like to sell it on.

[Dbahnson]

I think it goes in the "Early" category, so I've moved it there. Note that it's a left hand thread which is suggestive but not positively indicative of a pusher application. I'm hopeful that PMdec will chime in with his expertise on French props, which I agree this one probably is.

You are very wise to not try to refinish it in any way.

[pmdec]

Hi,

I think it is a French Levasseur propeller but to be sure you have to show a picture of the whole prop.
If it is a Levasseur, this prop was made around 1925 and could be for a Galvin* hydroglider. Some more infos after viewing a pic of the whole prop AND a pic of the fourth side of the hub (side opposite to the one you show with the measuring tape).

Best regards,
PM

* Attached pic: Dumond-Galvin founder share from 1925
Attached file: A PDF about Galvin brothers (in French)

[Oceandriver]

Thank you for your prompt responses. It is clearly an interesting object!
Attached are a couple of pictures of the 4th hub side as you asked for.

[Mtskull]

There is a fascinating page on the subject of “hydroglisseurs” here, which includes reference to Dumond-Galvin:
http://www.cmc-retronautisme.fr/hist...oglisseurs.htm

One thought: 18HP doesn’t sound like a lot of power to be turning a 2 metre propeller. One explanation may be that in this nautical, rather than aviation context, “CV” refers to the fiscal horsepower of the engine rather than its actual power output.

[Oceandriver]

French connection

Thank you again. This is fascinating. I live close to the south coast in UK, and not far from landmark aviation areas of Brooklands, Goodwood and Tangmere etc. Could the propeller have been used for craft development in this area?
I've added a couple of photos focusing on the blade tips. Let me know if anyone needs others.

[Oceandriver]

Hi,

I think it is a French Levasseur propeller but to be sure you have to show a picture of the whole prop.
If it is a Levasseur, this prop was made around 1925 and could be for a Galvin* hydroglider. Some more infos after viewing a pic of the whole prop AND a pic of the fourth side of the hub (side opposite to the one you show with the measuring tape).

Best regards,
PM

* Attached pic: Dumond-Galvin founder share from 1925
Attached file: A PDF about Galvin brothers (in French)

Fortunately I lived in France between 1983 and 2000 and have a good grip on the language!
Thank you for this information. I am sending more photos here of full length end to end and side views. The resolution reducing app I'm using is cropping the tips off the photos, but another discussion on this thread has photos of the tip ends. One tip is slightly damaged on the ply laminate.
Interested to read more as you reveal it!

[Dbahnson]

I think we still need a photo of the entire propeller, from tip to tip. If you can't get further away just tilt the camera diagonally to get a wider view.

I believe the 8 hole hub is not consistent with one of the lower horsepower Anzani engines. I have two Anzani 25 HP props which have a 6 bolt hole hub.

[Oceandriver]

Try this one. Open it up and move it around!

[pmdec]

Hi,

Ok, the last pic shows the entire prop and there is no doubt now that it is a Levasseur pusher (Levasseur from shape and markings geometry, pusher from the side of the hub where the central hole is flared).
As there is no airworthy stamp, it is probably not for anything flying. When Levasseur prop doesn't show airworthy stamp, it doesn't neither show a date around the central hole, but the prop number (30411) give a guess: around 1925 (Levasseur number 29870 is from December 10th 1924 and Levasseur number 32267 is from July 24th 1927).

Engine power is always marked as true power, never "administrative", so it is, effectivly, very low. A pic on the PDF I posted shows a glider with a Levasseur prop fitted on an Anzani engine, but the label tells "80" CV. And as Dave wrote, the hub is quite large for such a small power. Could it be a mismarking (18 for 80) ? As the prop was not "certified" (no airworthy stamp), it is possible. But you can also made a research about a 18 HP glider made by Galvin or Dumond-Galvin around 1925: it seems they made a number of prototypes...

Anyway, it is a very interseting piece of history: don't make any "restoration"!

Best regards,
PM

[Oceandriver]

Thank you very much. I had no idea when I started researching this that the subject could be so mysterious! It's taken me 5 years to get around to finding out about it!

Back to my original question. Is this item of any value? Is it simply worth an ebay auction, or should it go through a specialised auction?

I certainly agree it has some historical pedigree.

However, I have no particular desire to keep it and would put it up for offers. Would it be good to buff it up with beeswax polish first or just leave it?

[Dbahnson]

Thank you very much. I had no idea when I started researching this that the subject could be so mysterious! It's taken me 5 years to get around to finding out about it!

Back to my original question. Is this item of any value? Is it simply worth an ebay auction, or should it go through a specialised auction?

I certainly agree it has some historical pedigree.

However, I have no particular desire to keep it and would put it up for offers. Would it be good to buff it up with beeswax polish first or just leave it?

Just leave it! If you're selling it the new owner might elect to do something gentle or might very much prefer it to stay the way it is. I have a friend who has started collecting early props. Can I put you in touch with him?

[Oceandriver]

Hi,

Ok, the last pic shows the entire prop and there is no doubt now that it is a Levasseur pusher (Levasseur from shape and markings geometry, pusher from the side of the hub where the central hole is flared).
As there is no airworthy stamp, it is probably not for anything flying. When Levasseur prop doesn't show airworthy stamp, it doesn't neither show a date around the central hole, but the prop number (30411) give a guess: around 1925 (Levasseur number 29870 is from December 10th 1924 and Levasseur number 32267 is from July 24th 1927).

Engine power is always marked as true power, never "administrative", so it is, effectivly, very low. A pic on the PDF I posted shows a glider with a Levasseur prop fitted on an Anzani engine, but the label tells "80" CV. And as Dave wrote, the hub is quite large for such a small power. Could it be a mismarking (18 for 80) ? As the prop was not "certified" (no airworthy stamp), it is possible. But you can also made a research about a 18 HP glider made by Galvin or Dumond-Galvin around 1925: it seems they made a number of prototypes...

Anyway, it is a very interseting piece of history: don't make any "restoration"!

Best regards,
PM

Thank you very much for your detailed input on this propeller. I am inclined to agree with you that perhaps the cv marking has been made in error. As suggested by Dave, would a propeller fitted to an 18hp Anzani engine ever have required 8 fixing bolts. Can we therefore write-off the idea that it was destined for a glider application? One would assume that keeping weight down would be imperative for this application, and why add bolts where they're not needed!
Would an aircraft propeller clearly marked for "Hydro" use, and even named with the Galvin brand have required a certificate of airworthiness stamp if it was never destined to fly?
I love the photos of the hydro-glisseur on your pdf. This looks exactly like the one I have, right down to the copper shielding on the blades.
Once I have gathered as much provenance and background as I can on this, it will be for sale, and as with my earlier reply, any advice you have about selling an item like this would be appreciated.

[Oceandriver]

Hi,

Ok, the last pic shows the entire prop and there is no doubt now that it is a Levasseur pusher (Levasseur from shape and markings geometry, pusher from the side of the hub where the central hole is flared).
As there is no airworthy stamp, it is probably not for anything flying. When Levasseur prop doesn't show airworthy stamp, it doesn't neither show a date around the central hole, but the prop number (30411) give a guess: around 1925 (Levasseur number 29870 is from December 10th 1924 and Levasseur number 32267 is from July 24th 1927).

Engine power is always marked as true power, never "administrative", so it is, effectivly, very low. A pic on the PDF I posted shows a glider with a Levasseur prop fitted on an Anzani engine, but the label tells "80" CV. And as Dave wrote, the hub is quite large for such a small power. Could it be a mismarking (18 for 80) ? As the prop was not "certified" (no airworthy stamp), it is possible. But you can also made a research about a 18 HP glider made by Galvin or Dumond-Galvin around 1925: it seems they made a number of prototypes...

Anyway, it is a very interseting piece of history: don't make any "restoration"!

Best regards,
PM

Just leave it! If you're selling it the new owner might elect to do something gentle or might very much prefer it to stay the way it is. I have a friend who has started collecting early props. Can I put you in touch with him?

Of course Dave, feel free to pass on my email etc. I think you have that from my original contact with you. Cheers, Chris.

[Mtskull]

Can we therefore write-off the idea that it was destined for a glider application?

I think you will find that the use of the term “glider” in this context is down to a mistranslation of the word “glisseur” and that this is definitely an early airboat propeller.