Aircraft departing the same runway or parallel runways must diverge by how many degrees immediately after takeoff when separated by less than 2500 feet?

• A. 10 degrees
• B. 15 degrees
• C. 20 degrees
• D. 30 degrees

Answer: (B)

The requirement for aircraft departing the same runway or parallel runways to diverge by a specific number of degrees immediately after takeoff when they are separated by less than 2500 feet is based on minimizing the risk of wake turbulence and ensuring safe vertical separation. A divergence of 15 degrees is considered the appropriate angle that helps ensure that the aircraft can safely avoid the wake turbulence generated by the leading aircraft.

This 15-degree divergence is a standardized measure that allows for a sufficient lateral separation between aircraft, which is particularly important in the initial phase of flight when they are in close proximity and responding to the high-speed dynamics of departure. It effectively provides a margin of safety while maintaining efficient air traffic operations.

Variations in this required divergence can pose significant risks, as closer proximity can lead to potential encounters with wake turbulence, which can significantly affect the performance and stability of trailing aircraft shortly after takeoff.