What action should NOT be taken when an aircraft is responding to a TCAS Resolution Advisory?

• A. Coordinate with other controllers
• B. Issue control instructions that contradict their RA
• C. Provide traffic advisories
• D. Notify the pilot of potential hazards

Answer: (B)

When an aircraft is responding to a Traffic Alert and Collision Avoidance System (TCAS) Resolution Advisory (RA), it is crucial that the pilot is allowed to follow the guidance provided by the TCAS. The TCAS RA is specifically designed to prevent collisions by instructing pilots on the necessary maneuvers, such as climbing or descending, to maintain safe separation from other aircraft.

Issuing control instructions that contradict the RA would create confusion for the pilot and potentially undermine the effectiveness of the TCAS, which is a crucial safety system. This could lead to dangerous situations if the pilot is forced to choose between conflicting instructions from air traffic control and their own TCAS.

In contrast, coordinating with other controllers, providing traffic advisories, and notifying the pilot of potential hazards are all actions that support the pilot’s situation without interfering with the instructions given by the TCAS. These actions contribute to overall safety and awareness during critical phases of flight when an RA has been issued.