content_image/592263.jpg content_image/592274.jpg
<img src='content_image/592263.jpg'>

## Aspect Ratio 

The aspect ratio is another factor that affects the lift and drag created by a wing. Aspect ratio is determined by dividing the wingspan (from wingtip to wingtip), by the average wing chord. 

Glider wings have a high aspect ratio, as shown in Figure 3-19 . High aspect ratio wings produce a comparably high amount of lift at low angles of attack with less induced drag. 

## Weight 

Weight is the third force that acts on a glider in flight. Weight opposes lift and acts vertically through the CG of the glider. Gravitational pull provides the force necessary to move a glider through the air since a portion of the weight vector of a glider is directed forward. 

## Thrust 

Thrust is the forward force that propels a self-launching glider through the air. Self-launching gliders have engine-driven propellers that provide this thrust. Unpowered gliders have an outside force, such as a towplane, winch, or automobile, to launch the glider. Airborne gliders obtain thrust from conversion of potential energy to kinetic energy. 

## Three Axes of Rotation 

The glider is maneuvered around three axes of rotation: yaw (vertical), lateral, and longitudinal. They rotate around one 

<img src='content_image/592274.jpg'>

