What should be prioritized if two aircraft are on a collision course?

Prioritizing the separation of the arriving aircraft is critical when two aircraft are on a collision course because the primary goal in air traffic management is to ensure that aircraft maintain safe distances from one another to prevent mid-air collisions. In such emergency situations, immediate action is needed to create vertical or horizontal separation, which is essential to protect lives and maintain operational safety.

While the safety of passengers is certainly an overarching concern in all aviation operations, the safety protocols require that air traffic controllers first intervene to provide separation. This action aligns with established air traffic control procedures, which are designed to prioritize the physical separation of aircraft to mitigate the risk of an accident.

The speed of response from both pilots is also important, but it cannot be the priority in a controlled air traffic environment where the controller has the responsibility and authority to act first and coordinate efforts. Similarly, while handling other flights in the vicinity is a part of an air traffic controller's duties, it must not take precedence over resolving an imminent collision threat. Therefore, ensuring the immediate separation of the aircraft involved is the most effective and necessary course of action in this scenario.