What technique is used to determine the point straight below the aircraft during jump run?

The technique of determining the point straight below the aircraft during jump run involves creating two reference lines from the horizon and utilizing those lines for alignment. By identifying markings or features on the horizon and extending lines from them, skydivers can establish a target area beneath the aircraft. This method is crucial because it helps parachutists accurately locate their drop zone, compensating for wind drift and other factors that may affect their descent and landing trajectory.

Calculating wind direction is important, but it’s not the primary method for pinpointing the exact spot below the aircraft at the moment of exit. Visualizing the landing area provides general awareness, but it doesn't help in determining the precise vertical point beneath the plane. Estimating distance from the aircraft to the ground may aid in planning the descent but is not used to directly identify the drop zone directly beneath the aircraft. Thus, the line creation technique stands out as the most effective method for achieving accurate targeting during jump run.