Unknown Manufacturer

[Freibeuter]

Hi there,

I‘m trying to identify a wooden propeller from an aircraft that crashed about a 100 years ago in my grandparent‘s backyard.

To its dimensions
Length: 188 cm
Center bore diameter: 55 mm
Bolt hole circle: 115 mm
Diameter of hub: 144 mm
Number of bolt holes: 6
Bolt hole diameter: 10 to 11 mm
Hub thickness: 78 mm
The wood should be walnut.
And the plane crashed in the west of Germany.

Unfortunately there are absolutely no markings or any other signs on it.

Any support is welcome.
Thanks ever so much
Jan

[pmdec]

Hi,

Could you post pics of each side of the hub (> 4 pics)? On the 2 pics of the "flat" sides, please take each photo so the blade roots are visible (about 10 cm of the blade roots would be fine).

Regards,
PM

[Freibeuter]

Of course I can

There you go

[pmdec]

Hi,

Thank you for the perfect pics!

The "stories" which come with props are generally suspect, to the least... "Intact" propellers coming from a crashed plane are pretty rare, because when a plane crashes, generally, the prop is destroyed. In this case, IMHO, the witness marks on the first pic show that the prop has been mounted on a plane. And from the aspect of some of the bolt holes (ovalized and ripped), there was some "trouble", confirmed by tore lamination on the third pic.
So, the story could be true!
From the measures you gave and from the shape of the prop, it could be German. Probably before WW1, because during the war only military props were made and they were all stamped. More: Presence of wood knots would have "forbid" airworthyness.
So, I think it is a German prewar production. I hope Bob Gardner will give some more infos... but without marking, only the shape could lead to a manufacturer. Bob is the only one who can have an idea!

Regards,
PM

[Freibeuter]

The story is indeed based only on the memories of my father.
I had a chance to talk with him yesterday evening. So what he told me is that there was an aluminium fuselage in their backyard that he used to play with as a kid in the 1950s. And they had that propeller told to be from the WW1 era. He always related that prop to the fuselage, but yesterday he didn‘t feel too sure if it was ever installed there.
He told me there may be another origin, as one of his uncles was experimenting with flying machines.

Still I‘m keen to add any additional information to it, be it the manufacturer, the type of engine or whatever.

So thank you to anybody that contributes to this conversation.

Kind regards
Jan

[Dbahnson]

There weren't a lot of engines (at least during WW1) with hubs having only six bolt holes, so to PM's statement it may very well have preceded the war is likely spot on, but gathering enough evidence to know much more about it is a difficult task.


The connection to an aluminum fuselage, however, is almost certainly fiction.

[Freibeuter]

I must admit, when my father was referring to an Aluminium fuselage, there were some alarms ringing in my head.

When starting this post, I wasn‘t too sure if this propeller was more an early or a later one: The number of bolts and the diameter made me put it into the modern section, although the wood is darker, the leading edge is exposed / unprotected and the shape is not really symmetrical.

Still any hint regarding manufacturer or engine or so would be highly appreciated.

Kind regards
Jan

[Dbahnson]

The design is more typical of early propellers. If you look at the blade from the end along its length you may see evidence of hand planing the surface, which usually indicates an older prop (but could also be a simple reproduction. As PM points out, however, yours has the witness marks on the hub that show it has been mounted on a machined hub.

[Freibeuter]

Does anybody have contact with Bob Gardner?
I had sent him a PM, but he didn‘t answer.