A Little Information On Props
A propeller is basically just a wing that is rotating. Like a wing, it has an airfoil. It's top surface is curved which makes the wind travel faster than the wind on the bottom and thus causes lower pressure on the top. This causes the wing, or in this case the propeller to move in the direction of the lower pressure thus pulling the airplane to which it is attached, forward.
You might wonder about the shape of a propeller. It appears to be a twisted piece of wood. It is shaped this way so that it's tips spin faster than it's hub or center. The twist in the blade is shallow at the tip and steep at the hub. This provides even thrust from one end of the blade to the other.
The blades can be set to cut through the air at a shallow angle, or at a steep angle. So in theory, a 41-pitch prop would move forward through the air 41 inches when the prop blade had spun one complete revolution. In the same way, a 50-pitch prop would move forward 50 inches for one spin.
A fan and a propeller are actually the same thing. Both are rotating wings that push the air in one direction and experience a reaction force in the opposite direction as a result. Each experiences a "lift" force, typically called "thrust," in the direction opposite the airflow. If you put a strong fan on a low-friction cart or a good skateboard, it will accelerate forward as it pushes the air backward. Similarly, if you prevent a propeller plane from moving, its spinning blades will act as powerful fans.
Right-handed props follow the "right handed rule", just like right-handed screw threads. A right-handed prop rotates clockwise when viewed from behind. Most American engines (and therefore their propellers) tend to turn in a right-handed direction when mounted in what is called a tractor installation. (i.e.: prop on the front of the engine). If you mount it as a pusher, you need to use a left-handed prop to make the propwash blow aft and the airplane fly forwards. Installing a prop backwards does not turn it into a pusher, it just makes it less efficient because the airfoils are now backwards and upside-down.
All that technical stuff aside, our beautiful prop with clock is just great to look at and will also provide you with the time. Mount it on the wall anywhere for a great conversation piece. You're going to feel like an ace if you don't already!
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