How does a paramotor work?
Paragliders generate lift, the upward force that keeps them in the air, through a combination of Bernoulli's principle and the wing's shape. When air flows over the curved upper surface of the wing, it travels faster than the air passing beneath the wing's flatter lower surface. According to Bernoulli's principle, the faster-moving air creates lower pressure, while the slower-moving air underneath creates higher pressure. This pressure difference generates lift, pulling the wing upward.
Wing Shape: The shape of the paraglider wing is crucial for generating lift and controlling flight. The wing typically has an elliptical shape when inflated, with a curved upper surface and a flatter lower surface. The curved upper surface increases the distance the air must travel, creating a pressure difference and generating lift. The flatter lower surface allows for better stability and control.
Control Lines: The pilot uses control lines to manipulate the shape of the wing and control its flight. By pulling or releasing the lines, the pilot changes the wing's angle of attack (the angle between the wing's chord line and the oncoming airflow). Altering the angle of attack changes the lift and drag forces acting on the wing, enabling the pilot to control the speed, climb, or descent of the paraglider.
Drag: Drag is the resistance encountered by the paraglider as it moves through the air. It is caused by several factors, including the shape of the wing, the friction between the air and the wing's surface, and the pilot's position. The paraglider is designed to have a relatively low drag to maximize its glide performance and efficiency.
Glide Ratio: The glide ratio is a measure of the distance a paraglider can travel horizontally compared to the vertical distance it descends. A higher glide ratio indicates better efficiency and longer glides. It is influenced by factors such as the wing's aerodynamic performance, pilot technique, and environmental conditions. Advanced paragliders can achieve glide ratios of around 8:1, meaning they can travel 8 units horizontally for every unit of descent.
Thermals and Lift: Paragliders can gain altitude by utilizing thermals, which are columns of rising warm air. When a paraglider encounters a thermal, it can circle within it, ascending with the rising air. Thermals are created by temperature differentials in the atmosphere and can provide significant lift for paragliders.
Weight Shifting: Weight shifting is an essential technique for controlling a paraglider's roll and yaw. By shifting their weight to one side or the other, the pilot induces a change in the wing's shape, creating a roll moment and initiating a turn. Weight shifting can also help the pilot maintain balance and stability during flight.
Power and the motor: Paraglider pilots rely on thermals, ridge lift, and natural elements to get altitude, and stay in the air. Paramotor pilots have the luxury of a motor to give them altitude. As the pilot applies power to the motor, it generates thrust, and changes the angle of attack by pushing the pilot forward.
These are some of the key mechanics and aerodynamics involved in how a paraglider works. Understanding these principles allows pilots to manipulate the wing and navigate through the air with control and efficiency.