What should be done if a towbar becomes disconnected during an aircraft movement?

Applying the brakes immediately is the most appropriate action if a towbar becomes disconnected during aircraft movement. This response is critical for ensuring safety by preventing any uncontrolled movement of the aircraft. When the towbar disconnects, the aircraft can lose directional control, posing a significant risk to personnel and equipment nearby. By stopping the aircraft promptly using the brakes, ground crew can assess the situation and take necessary steps to secure the aircraft, preventing potential accidents or damage.

In situations involving aircraft movement, safety protocols dictate that any abnormal condition should be addressed immediately to mitigate risks effectively. Therefore, halting movement allows for a safer approach to addressing the towbar disconnection issue without endangering anyone or anything on the ramp.