French Serie 540

[BrokenWing]

I have photographed the next wooden 2 blade propeller and made the pictures public in another flickr album

look here for the full set of pictures if you would (thanks) : https://flic.kr/s/aHsmxocGB1

I initially had not noticed the numbers on the side as they are extremely faint and (as you'll see) very tricky to photograph.

I have drawn them out "SERIE 540" "NUMERO 16234" and then a strange maker's mark ...I hope this helps their identification and is furthermore of interest to the forum.

The propeller measures 254cm (pretty much 100inches bang on) has 8 holes, a hub diameter of 7 an half inches or 19cm and it has a depth of 5 and a half inches or 14cm.

The number appears to not be on your current database!!

Any help on identifying the makers and aircraft would be wonderful - many thanks in anticipation.

[Dbahnson]

It's French, and I'm not at home where I can look up that "Serie" number, which identifies an engine and aircraft usage. It's almost certainly WW1 era, not "modern" category.

Unfortunately, it too has been hacked up for a hub instrument of some kind.

[BrokenWing]

Thanks for getting back so quickly...

I'll be very interested if you can unearth more info on the piece when you are able - cheers

(and yes I think the original thread was posted in the WW1 era part of the forum, but was moved after you identified that first one to be a modern prop - sorry I didn't notice until after following up with this more recent post)

brilliant site - very impressed with the knowledge you guys have!

[Bob Gardner]

Well, I too am away from my databases. We must await Dave or Pierre-Michel looking up your serie numbers. SFA is the French airworthiness stamp. The shape of the blade is very familiar and I believe it was used on British and French aircraft which used the Hispano-Suiza engine, such as the British SE5A.

With kind regards,

Bob

[Bob Gardner]

Postscript,

Don't worry too much about the damage to the hub. It is a common affliction where props had clocks fitted to them in the 1920s and is typical of the age. It is part of the history of the many of these props. If you wish, you could employ a cabinet maker to cut a smooth finish to the damage and to then insert a wooden plug, complete with drilled bolt holes. But it is a good looking prop from a famous WW1 aircraft, in typical condition of the age. Enjoy!

With kind regards,

Bob

[pmdec]

Hi,

Infortunatly, the Levasseur serial 540 is ot in the "French papers" where there are the correspondance between serial number and destinated plane...
It is a "late" serial (designed after the end of 1917). This serial is in "American papers" but without any destination indicated. The only way to know for wich aircraft it was made is to read the markings on the opposite side where there are serial and prop number. Could you take a clear one?
Another "trouble" is the length you measured is very different from what is written in American papers: 254 cm vs 272.

Regards,
PM

[pmdec]

Hi,

Infortunatly, the Levasseur serial 540 is not in the "French papers" where there are the correspondance between serial number and destinated aircraft...
It is a "late" serial (designed after the end of 1917). This serial 540 is in "American papers" but without any destination indicated. The only way to know for wich aircraft it was made is to read the markings on the opposite side where there are serial and prop number. Could you take and post a very clear picture of this side?
Another "trouble" is the length you measured is very different from what is written in "American papers": 254 cm vs 272.

Regards,
PM

[Bob Gardner]

Bonjour mon Ami Françoise,

Why are you giving us this bifocal version, or double copies. Is this what life is like after Brexit?

Avec cordialement,

Bob

[pmdec]

Bonjour mon Ami Françoise,

Why are you giving us this bifocal version, or double copies. Is this what life is like after Brexit?

Avec cordialement,

Bob

Hi Bob,

Are you sure Brexit will happen some day?

Bifocal? I always "speak" about WW1 French propellers database using this two essential database: The French one (compiled bythe SFA) and the American one, found inside Gorrell's. And yes, there are some other infos but very sparse and dispersed. The props which are in American and not in French papers were made in 18, because the French nomenclature date from the end of 1917.

Regards,
PM

PS : Have you a French keyboard? Or did you type Alt + 135 each time to write Français (Françoise is a surname...)?

[Bob Gardner]

Pierre-Michel, mon ami; My brain has been pre-occupied by the shape of this prop which strikes a considerable chord in what is left of my 75 year old brain, and I have much suspected that my original thought that it is of French design for a Hisso is wrong.

I have therefore searched the internet and the books of some fellow called Bob Gardner, whose books I recommend, and have found that it is of French design for a 110hp Le Rhone engine, but also made in Great Britain for the Nieuport Scout by the Lang Propeller Co with the drg number LP3420. Now I can rest easy.

With kind regards,

Bob

[pmdec]

Hi,

It is absolutly certain, from the SFA square stamp and the letter "L" and the digit "1" on its left side that the prop was made in France by Levasseur. But there is more:
- The prop shape is absolutly typical of Levasseur props.
- The lettre U on the right side of the SFA stamp is the very sign of an inspector working in Levasseur workshop.
- Levasseur and Régy props are the only French ones of the WW1 era which may have a three digits serial number between 310 and 800.
I don't know for which engine and aircraft it was designed because I have not this details in my databases, but from the shape of the (remains of the) hub, it was a pusher, perhaps for a seaplane (but possibly also for a Voisin or for a Farman or ?). If BrokenWing has not also a broken arm, he will made a clear pic of the markings which will tell us for which aircraft and engine it was made

Regards,
PM

[Bob Gardner]

I'm sure you are correct, Pierre-Michel.

As I mentioned, having suggested originally that the prop might be for a Hisso engine, I began to have doubts, and I knew I had a photo of a similar prop somewhere. I found the photo in one of my books, in the chapter on Lang Propellers where there is a photograph that is of French design for a 110hp Le Rhone engine, but made in Great Britain for the Nieuport Scout by the Lang Propeller Co with the drg number LP3420. Now I can rest easy.

My observation is only that the British Lang propeller made for a 110hp Le Rhone with drg number LP3420 for a Nieuport Scout is very similar to the shape of the prop in the photo. I believe that Nieuport Scouts bought for the British Admiralty came with two spare propellers. I have long thought that these were copied by Lang who was the prop maker for the Royal Navy.

I have been horrified all day by the recurring news film of the fire in Notre Dame and am much relieved that the outer shell of the Cathedral remains intact. I used to visit Notre Dame after attending NATO conferences twice a year at Quai D'Orsay circa 1984-85.

with kind regards,

Bob

[pmdec]

Hi Bob,

Thank you for your kind words about Notre-Dame!

The BrokenWing prop is a left handed pusher: look at his pics "06" and "07". The side of the hub we are seing is the intrados side. The center hole is not tappered, so it can't be placed against the engine. Thus, it is the other side of the hub which was against the engine and then it is has to be a pusher prop. But I stand to be corrected!

Best regards,
PM

[Dbahnson]

I'm not quite positive that it's a pusher, although it's certainly likely. But the SPAD 13 used a 200 hp Hisso engine that was geared, so the rotation was reversed in a tractor configuration.



I agree that one would expect the "engine side" of the propeller to be rounded for easier mounting on the crankshaft, but was that always the case?

[pmdec]

Hi,

If the data from Gorrell's are right, the Levasseur serial 540 was 272 cm long and has a 155 cm pitch. This pitch is way too low for a geared engine. BUT, from BrokenWing measures, the length is only 254 cm and the blade tips don't seem reshaped. So... Reading (or guessing!) the markings could be the only way to know...

About the "rounded" central hole: it is not there to improve the implementation of the prop but to fit the shape of the metallic hub. Some props have both central hole ends rounded, but the only props without any side rounded I have seen are the front prop from two-pieces four-bladed or not finished props (but then, there is no airworthy stamp).
BUT I can't be sure there is not somewhere a prop of the WW1 era without rounded central hole: I would be pleased to see one!

Levasseur made a prop for the geared HS of SPAD 13: the serial 586. Length 255 cm, pitch 230 cm, blade width 182 mm, central hole 80 mm (rounded on intrados side), hub thickness 175 mm. I can post pictures.

Regards,
PM