Have You Heard About Boomerangs?
A lot of people have heard about boomerangs, or “booms” as they are sometimes called, but very few people have thrown one or know how they work. Although the Australian Aborigines are generally credited with inventing the returning kind of boomerang more than 10,000 years ago, many cultures, including Egyptians, Hopi Indians, people in southern India, and people in Africa, Polynesia, and northern Europe, have used the non-returning kinds as hunting sticks and as weapons.

Here is a chance to make a boomerang of your own and test its flight path. Trace and cut out a four-wing boomerang from a file folder (like the picture below), hold it horizontally, and practice throwing it a few times. What does its flight path look like? It probably went pretty straight. Now hold the boomerang vertically, and give a spinning motion to the boomerang as you throw it straight forward. Now how does it fly? Did you try to catch it? It should come back to you. How far away did it travel? Finally, wrap or twist the boomerang’s wings slightly to see what effect a bit more curvature has on the flight. You may notice that the boomerang slows a bit. How is the boomerang working?

A simple explanation in how the boomerang works is to think-about three forces (based upon scientific principles) that are often related to how other objects move, such as an airplane, merry-go-round, and bicycle. First, similar to an airplane, the boomerang is experiencing “lift” created by the arms (airfoils) of the boomerang enabling it to 'fly'. Second, the boomerang is experiencing motion similar to a ‘merry-go-round’ where the relative spinning motion creates an unequal lift on each arm increasing its ability to change directions. Third, similar to a spinning bicycle wheel, the boomerang also has gyroscopic motion, helping the boomerang to turn back to you in a consistent path. Pretty fun huh? You can experience three fun forces in just one flip of the boomerang!

To learn more about boomerangs, and the forces that act upon them, access Panel 4 of our AIA Back of Posters Resources Page, or go directly to this excellent more detailed NASA lesson on Boomerangs: http://www.grc.nasa.gov/WWW/K-12/TRC/Aeronautics/Four_Wing _Boomerang.html