What is the primary function of ground spoilers during landing?

The primary function of ground spoilers during landing is to aid in deceleration. When the aircraft touches down, ground spoilers deploy automatically or can be activated by the pilots to disrupt the lift generated by the wings. By doing so, they effectively transfer the aircraft's weight to the wheels, increasing the load on the tires and enhancing the friction between the tires and the runway surface. This increased friction allows for more effective braking, thereby shortening the landing distance and improving the overall safety and control during landing.

While other functions may be related to the aircraft's performance, such as drag reduction or lift increase, they do not convey the fundamental purpose of ground spoilers during landing, which is explicitly aimed at increasing deceleration and improving braking efficiency.