What type of tower display must not be used for providing radar services or traffic advisories?

The type of tower display that must not be used for providing radar services or traffic advisories is the uncertified display. Uncertified displays do not meet the requirements and standards set by aviation authorities for reliability and accuracy in radar services. These displays may lack essential features, such as proper calibration, timely updates, and sufficient redundancy measures, which are crucial for the safe management of air traffic.

In contrast, certified displays have undergone rigorous testing and validation, ensuring that they can accurately represent radar data and support safe decision-making in air traffic control. Their use in providing radar services is essential to maintain situational awareness and effective communication with pilots.

Thus, critical services like traffic advisories, which depend on precise and reliable data, should always be conducted using certified displays to ensure the safety and efficiency of air traffic operations.