What details about the aircraft should be relayed if longitudinal separation is less than 10 minutes?

When longitudinal separation between aircraft is less than 10 minutes, it is critical to relay information about the longitudinal separation used between those aircraft. This information is essential for air traffic controllers to ensure that they have a clear understanding of the separation status and can manage air traffic safely and efficiently.

Longitudinal separation is a key aspect of maintaining safety in the airspace system. By communicating the specific separation being used, controllers can monitor the distance and altitude of the aircraft, thus preventing potential conflicts. If the separation is reduced to less than 10 minutes, it becomes more challenging to guarantee safety, so sharing this information helps all parties involved, including other controllers and flight crews, be aware of the current situation and make necessary adjustments in their operations.

In this context, while details regarding weather systems, aircraft fuel calculations, or flight crew availability are also important for overall operational efficiency, they do not directly address the immediate concern of maintaining safe separation between aircraft operating in close proximity.