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121155
08-01-2015, 09:42 PM
Hi, new member here, i picked this up in a shop a couple weeks ago and cannot find much info on it. It is of 2 piece construction and is very light in weight. There are 4 bolt holes of which were missing, the lag bolts are actually holdimg the prop on my wall. Any information to help narrow down its origin would be great

Measures 74 inches tip to tip and has a 2 1/4 bore

Thanks in advance

Oliver

Dbahnson
08-01-2015, 10:17 PM
There's just no way it can be identified by that information alone. On the other hand, 4 holes suggests non-aviation usage, or possibly an ultralight or some other non-certified aircraft, even industrial use of some kind.

A photo is a good start, but right now it could be almost anything. Not sure I understand "4 bolt holes of which is missing". :confused:

121155
08-01-2015, 10:29 PM
Pictures attached, let me know if any other pics would help with id

121155
08-01-2015, 10:33 PM
More pics, guess i can only upload ome at a time on iped

121155
08-01-2015, 10:34 PM
Sorry i meant the original bolts are missing

Dbahnson
08-02-2015, 07:57 AM
Sorry i meant the original bolts are missing

You can tell from the circular coloration of the wood near the bolt holes that there was a metal plate behind the nuts, and there was probably one on the back of the assembly as well, meaning that the two blades were held together with a hub which attached it to a shaft of some kind. That's a typical arrangement for a wooden propeller, so it's what you'd expect to see.

I certainly don't "recognize" it as one I've seen before, and if it was used on a certificated aircraft of any kind it would have stamped information on the hub or elsewhere, usually with a design or "drawing" number linking it to a blueprint.

So my best guess is that it is homemade, or possibly industrial use of some kind such as a fan. I'm not aware of any early (pre WW1) propellers using 4 blades and by the time they came into use there was a standard nomenclature and stamping used to identify them.

It looks to me from the hub close-up that only one of the two blades is notched. That would make an inherently weak design which would fail at any kind of high speed, further suggesting that it was non-aviation in use.