Curtiss Experimental Propeller

[Proplexed]

Hello to All,
I hope to find out some information about my Curtiss propeller I have owned for the past six years. What I do know: 96" Long, Hub Thickness is 6", 3" center bore diameter, 6-3/4" Bolt Circle, Eight 1/2" Holes. I will upload photos showing the Curtiss Aeroplane & Motor Co., Inc. decals. The Propeller has the following markings: DRAWING # EX 16997 - D - 80 - P - 48 - 2. CURTISS PROPELLER # 1801 LHMF - - OAK -
There also appears to be a circular stamping close to the hub, not sure what this is but it looks deliberate.
It also appears to be a "pusher" style propeller found on Curtiss flying boats of that period.
Questions: Does the EX drawing # mean it was Experimental? Garden City, NY was home to the Curtiss Engineering Corporation Building that was dedicated to aviation research and development. This building was opened in 1918, suggesting the propeller is almost 100 years old.
Also, does the paint and coloring suggest a military application?
I look forward to any response as to what Curtiss Aeroplane and what motor this Propeller may be linked.
Thanks,
Matt

[Dbahnson]

The "EX" often refers to experimental. I'll see if I can match any of those numbers, but it may be difficult to identify. I think your assumption about a pusher application is probably correct.

Very nice decal, and nice to see that the prop is still in original condition. Can you post a close up of the hub? It would be interesting to see if it had been mounted or if it was kept as a spare.

[Proplexed]

Thanks for the reply!
It has definitely seen use, I will post more pics of the hub and prop strikes.
It does seem to be completely original.
Thanks in advance for your research results.
Matt

[Dbahnson]

Yes, the hub clearly has the "witness marks" from the impression of the metal hub that occurs with expansion and contraction of the wood between the metal hub compression plates.

Even though we don't know what it was used for, this is an excellent example of a prop that needs to be preserved rather than "restored". It's possible that the "LHMF" refers to "left hand" something, although I don't know what.

See if you can match the hub dimensions to engines on this chart. It should eliminate some of the commonly used engines and may help narrow down the other possibilities.

[Proplexed]

Thanks Dave,
I have referenced the hub dimension chart and feel that this propeller may have been fitted to a Wright A.
Is it rare to see an experimental prop of this era? My thought is that most were destroyed, hence the difficulty I have had trying to find information. I have never seen this decal on another Curtiss propeller. I have done image searches and referenced many propeller and Curtiss web sites over six years.
Have you seen this decal before?
Regards,
Matt