What is the primary information that should be maintained on a flight progress strip?

The primary information that should be maintained on a flight progress strip is only the necessary current data. Flight progress strips are designed to provide controllers with up-to-date and relevant information regarding a specific flight, including its current status, such as departure and arrival airports, destination, altitude, and route. This focused information allows for efficient management of air traffic and ensures that controllers can quickly access the essential details needed to make informed decisions during their operations.

Historical data and complete technical specifications are not necessary on the progress strip, as they can clutter the information and could distract from managing live traffic. Additionally, details about previous flights do not contribute directly to the management of current traffic and can also be considered extraneous to the immediate needs of air traffic control. By maintaining only current data, controllers can effectively streamline their workflow and enhance situational awareness.