An airplane practicing turns around a point with a direct tailwind will be at its slowest speed when it is heading:

When an airplane is practicing turns around a point with a direct tailwind, its ground speed is influenced by the wind's direction. The airplane will be at its slowest speed when heading directly into the wind, as the headwind opposes the aircraft's forward motion, reducing its effective speed over the ground.

As the airplane performs a turn around a point, its airspeed remains relatively constant. However, the variation in ground speed caused by the wind is significant. When heading straight into the wind, the aircraft experiences a headwind that decreases the groundspeed to its lowest point. Conversely, when flying with a tailwind, the groundspeed is increased, leading to a faster speed over the ground.

The situation also contrasts with flying in a crosswind or ahead of the flight path, where the aircraft's speed is not maximally affected by the opposing force of the headwind. Therefore, in a turn around a point, the combination of maintaining a consistent airspeed and experiencing the opposing force of the wind results in the slowest ground speed when heading directly into the wind. This understanding is crucial for pilots as it influences their control and maneuverability during operations near obstacles or when performing turns around a point.