I assume this cool hand carved propeller once attached to what would have been quite a large model airplane, but while the plane may have crashed and burned, happily someone salvaged this. The propeller is held to the mount by a wire with a couple of spacers in between the two (see photos), allowing the propeller to turn, but holding it a bit loose. Really I think the best thing (unless repurposing intro some new construction) is to hang it by the wire from a nail or hook on the wall--a fabulous looking sculptural object and surely good luck for safe future travels. (In this scenario, the wire holds the propeller tight to the mounting piece, keeping it from spinning while up on the wall.) 

12 1/4" span; mount is 4 7/8" wide x 3 1/4". Made of very very soft wood. Some paint loss and scrapes, all to the good I think. The wire on the backside it strong and a bit of a challenge bend as desired; as currently configured, it's ready to loop over a nail or hook on the wall.