What happens when you fly into the air? How did this happen?

It will be bumpy, especially for small planes. There are many reasons for airflow. For example, if the planes cross, the wake of the front plane will produce airflow, which will make the rear plane bump. There are also strong convective weather such as thunderstorms, which may also produce very strong airflow. The most serious thing is wind shear, which will cause the plane to descend rapidly, get out of control, and crash directly if the flying altitude is relatively low.