What condition is necessary for RTO to be applied?

For rejected takeoff (RTO) to be applied, one key condition is that the aircraft must be traveling at a significant speed, specifically above a certain threshold, which in this case is 60 knots. This speed is important because it represents a point at which the aircraft's performance characteristics, such as lift and aerodynamic control, change significantly. If the aircraft is below this speed, it is often still in a stage where it can stop safely without significant concern for runway distance or aircraft control.

Applying RTO at speeds above 60 knots indicates that the pilots are acting within the operational parameters of the aircraft's braking and control systems, emphasizing safety and effectiveness in scenario management. At this speed, the aircraft is also more likely to experience an adequate response from the braking system, ensuring a more controlled and effective stop if necessary.