Need help identifying propeller...photo atached

[sparrowhawk]

I have a wooden propeller I need help identifying. It is 71.5" long, 9" tall and the center is 4.5" thick. I cannot find any labels or markings. It reportedly came from a Wright Bros. 4 Cyl plane that crashed in 1910. I've consulted with a couple of aviation history buffs who are skeptical of this claim and think the propeller is probably from the 1920s, but couldn't really explain why.

Does anyone have information about this type of propeller that would give me a clue about its age, what type of plane it came from?

Thank you in advance!

[Dave]

I am skeptical about virtually ALL of those claims, and this is certainly no exception.

The hub and construction is not typical of the early Wright flyers, but I'm not sure when they began to change them to more "modern" designs. I think it will be difficult to establish and age and/or usage of yours, particularly without any manufacturer's markings or other identifying attributes. It may not even be designed for an aircraft usage, as there were many other types of propeller applications.

Most of the early aircraft propellers had to have fairly large diameters (lengths) due to the low RPM of motors of that era. Propellers of the size of yours became relatively common in the mid century when engine RPMs were commonly higher.

The drilling of the hub is certainly "unusual" and looks very haphazard.

[sparrowhawk]

Thanks for your prompt reply, Dave. This propeller was included in a collection of early aviation items that are slated to go on exhibit at a museum in December this year. This propeller originally came from a midwestern college, where it was displayed in a building for years. It was removed from the college building in the 1930s and donated to the museum and it has been in storage ever since.

I actually found a photo of the 1910 plane crash it is supposed to come from and noticed that the propellers on it are completely different and quite a bit larger. I also had wondered about the hub holes because they seemed very sloppy. I thought I had better investigate...

I was hoping to find some kind of info about this propeller that would help me include it in our story of early aviation history, but I don't want to put it on exhibit if it is not an authentic item. We get so many wild stories with the objects that come into our collections. So many of them turn out to be pretty far from the truth! You would not believe how many copies of the "Declaration of Independence" that people bring in to us, thinking that they have the real deal!

[Bob Gardner]

Good Morning Sparrowhawk,

An intersting puzzle. I have a little knowledge about European props but not much about early American props. From a European point of view your prop has an old 'paddle' shape which dates it, I think, to around 1910 or 12. It is laminated which also indicates that it is later than 1909 when Lucien Chauviere in France invented the technique. The pattern of holes in the hub is typical of early aviation where a prop was removed from one type of aero engine and used on another. There is an evident repair to the right hand blade.

I believe early American props were often carved from solid oak. This and the European look of your prop suggest that your prop might have been imported into the States. But a six foot diameter is very small, unless it was made for a USAS penguin, a full size but flightless aircraft with short wings, and a small propeller, which was used for pilot ground training; viz; starting the engine, and manouvering the aircraft on the ground.

The USAS had a training base at Issoudon in France with about 12 separate airfields, each dealing with a stage of flying training. Two or three (I think) would have had penguins, called school machines by the French, and these were probably procured in France. This is a possible scenario for your prop.

Perhaps Pierre-Michel Decombeix could advise us if your prop might have a French origin.

With kind regards,

Bob

[pmdec]

Hi,

Sorry, Bob, but I can't give any reasoned response to this one with this picture only. My first impression is the same as Dave. But if it is true (and proved) this piece came from an exhibition closed around 1930, it could be more interesting to dig some more.

I can't find any regular pattern for the hub holes, except, perhaps, one with 4 holes (see the cropped and lightened sparrowhawk picture). But even this one is not totally satisfactory : the blue and green lines are not perpendicular (but it may be from picture shooting angle). And what about other holes? And central one?

I do not see laminations, and the shapes of the two broken and repaired parts on the right tip seems to me an indication that the propeller is one piece and not laminated. Is it?

Perhaps, with close up pictures of the four sides of the hub, it would be possible to be more conclusive.

Regards,
PM

[Bob Gardner]

Bonjour Pierre-Michel,

Yes, I concede that my scenario was speculative, but it does provide an answer to the facts we've got. I do think the prop is laminated. Enlarge the photo and look at the top half of the left blade; are there not two laminations there and one lower down on the blade?

How's the book on French props going? Part 3 and part 4 of my book on British props are at the printers and part five is nearly finished. Then I shall start on German props, for which I have gathered all the info that I can, and am much looking forward to starting.

Avec le Respect,

Bob