Which airspace control measure uses different times of day?

The choice of Timed as the correct measure in airspace control is based on the approach of managing airspace usage by delineating specific times for different operations, effectively optimizing the flow of air traffic based on the time of day. This measure allows for the scheduling of aircraft operations in a manner that minimizes conflicts and enhances safety and efficiency.

By implementing a timed control measure, airspace can be allocated for various uses at specific intervals, which is particularly beneficial in busy airspace where the demand for access may vary significantly between times, such as peak and off-peak hours. This helps in managing the air traffic environment more effectively, ensuring that aircraft are spaced out appropriately in both time and altitude during their operations.

This understanding emphasizes the importance of temporal organization in operations, particularly in environments where air traffic density fluctuates based on time-related factors. Therefore, the Timed airspace control measure not only aids in maintaining a structured flow of air traffic but also ensures that operational needs are met without compromise to safety or efficiency.