I need help identifying a WWI prop

[Dave]

The "P.P." probably refers to "Paragon Propeller" and the number that follows should be the design number.

Is the hub notched?

Pictures should help, but there are LOTS of possibilities.

[Rjzac67]

I have a wooden propeller that I have been told is from WWI.
There are some markings on it. I will post pics of the prop. The markings are
6 65, F.C.R., 9 -6"x 5 0 0, P.P ___ R.H., TYPE 91-H

Any help would be much appreciated!