What must be established as a protocol before allowing visual separation to proceed?

To allow visual separation to proceed, it is crucial to first establish other approved separation. This means that before visual separation can be utilized, air traffic control must ensure that there are existing separation standards in place that meet safety requirements. This typically involves having an understanding of the relative positions and performance of the aircraft involved so that visual separation can safely take over from those existing separation standards.

Visual separation relies on the pilots maintaining visual separation from each other once cleared, which can only be confidently given when it is known that normal separation parameters are already established. This is essential for ensuring the safety of operations in controlled airspace, where the aircraft are expected to maintain proper distances from one another under both visual and instrument flight rules.

The other aspects, such as clear communication with pilots, valid VFR weather conditions, and radar tracking of both aircraft, are important for safety and situational awareness, but they do not serve the foundational role that establishing previously approved separation does.