How Boomerangs Fly http://static.ddmcdn.com/gif/boomerang-biology.jpg If you were to throw a tree branch with the same speed and at the same angle as a boomerang, the stick would fall to the ground first.  But why is this so? The tree branch is one unit, one piece of material.  The boomerang is actually made up of two parts.  The two pieces are connected at one point, called the central point shown in the above picture.  This is where the boomerang rotates about and is stabilized as it fly's through the air.  Now the two pieces that are molded together are not just two straight components, but they are actually wings.  One side is  completely flat, while the other is rounded off.  Just like an airplane wing.  Weird enough, this is where the airplane wing design came from.  the Wright brothers noticed the dimensions of a boomerang and tried it on a plane (gotheeem!!  I have no idea where the design of an airplane wing came from).                                                                                              The picture above and to the left explains how the boomerang stays in the air longer than a tree branch.  When the boomerang is thrown, the top of the boomerang alternates and this makes the boomerang glide through the air longer.  the other pictures shows the two leading edges of a boomerang facing in the same direction.  If you think about it, a boomerang is just like a helicopter propeller that rotates without any fixed object to move about.  The force that moves the boomerang is applied directly at the central point of the boomerang.  So if you throw the boomerang horizontally, the force acting on the boomerang is perpendicular to the motion, so it should go up like a helicopter.  And if you throw it vertically, it will veer off to the left or right, correct?  Wrong!  It is perfectly reasonable to thing that this would happen, but the laws of physics will explain how a boomerang moves like it does.