We know about gravity, the downward attraction force for bodies that have mass. We have learned about lift, thrust, and drag. Basically, these four types of aerodynamic forces are what fly a glider drone. In a short definition, the gravity is an upward force, the thrust is the forward force, the drag is the backward force, and the lift is an upward force.

To fly the glider, the thrust must be greater than the drag and the lift must be greater than the gravity. The easiest option is to cancel the opposite forces.

The take-off and climbs must take place to fly the glider.

All the forces should be balanced, otherwise the glider will fall apart. The wing can generate lift, as we have studied before. The air approaches the wing and then splits at the leading edge of the wing and meets again at the trailing edge; therefore, the air must go faster over the top of the wing as this distance is larger. For a working glider, I suggest the following measurements:

• Wing span: 50-60 cm
• Aspect ratio: 9-10
• Angle of attack: 3-4 degree