How do birds fly?
Have you ever seen a bird take off and wondered how on earth they fly? Well that's why I made this explanation.
Firstly I will explain the four forces:
Lift is a force that helps to make the bird go up. Drag is a force that helps to slow the bird down . Thrust is a force that helps to make the bird go forwards. Weight is a force that helps to make the bird go down.
If you really want to know how birds fly, you need to listen to me. Birds use their strong muscles, hollow bones and wings to get off the ground. Now everyone knows that humans can't fly because our muscles aren't strong enough to overcome gravity and our bones are not hollow, but we can fly by making a plane.
Planes have a streamlined shape to reduce the drag slowing them down. To help them land the planes have flaps to help them produce drag and weight and reduce thrust and lift. The wings make lift by changing the direction and pressure of the air that pushes into them as the engines provide the thrust to shoot them through the sky. The drag and weight both help the plane go down. The wind that gets trapped under the wings creates lift. The rudders help the plane move left and right and the elevators change the pitch of the plane (up and down). The two stabilisers, the horizontal one and the vertical one, both make the plane stable.
My conclusion is that humans are not able to get enough thrust and lift to get off the ground and that we are too heavy. The gravity is always bringing us down.