Which statement correctly describes how ballast affects wing loading, stall speed, cruise performance, and when ballast should be released?

Which statement correctly describes how ballast affects wing loading, stall speed, cruise performance, and when ballast should be released?

• A. Ballast decreases wing loading, lowers stall speed, and worsens cruise performance; release before ascent.
• B. Ballast is retained during climb and released before landing to reduce landing speed and improve handling.
• C. Ballast increases wing loading, raises stall speed but improves cruise speed and cross-country performance; ballast is typically retained during climb and released before landing to reduce landing speed and improve handling.
• D. Ballast has no effect on wing loading.

Answer: (D)

Ballast changes the weight of the glider without changing its wing area, so it directly increases wing loading (weight per unit wing area). When wing loading goes up, the stall speed also goes up because you need to reach a higher airspeed to generate enough lift to support the heavier aircraft. At the same time, a heavier glider flies faster in cruise because the speed for best glide shifts to a higher value and you can maintain higher forward speed between thermals, improving cross‑country ground speed even though you’ve sacrificed some climb efficiency and thermalling ability. The typical practice is to keep ballast in place during climb or cruise to take advantage of the higher cruise speed, and then dump ballast before landing to reduce landing speed and improve handling on approach and touchdown. This matches the described correct statement. The idea that ballast has no effect on wing loading is incorrect, and the option mentioning release timing without addressing the weight, stall, and cruise effects isn’t a complete description.

Ballast changes the weight of the glider without changing its wing area, so it directly increases wing loading (weight per unit wing area). When wing loading goes up, the stall speed also goes up because you need to reach a higher airspeed to generate enough lift to support the heavier aircraft. At the same time, a heavier glider flies faster in cruise because the speed for best glide shifts to a higher value and you can maintain higher forward speed between thermals, improving cross‑country ground speed even though you’ve sacrificed some climb efficiency and thermalling ability.

The typical practice is to keep ballast in place during climb or cruise to take advantage of the higher cruise speed, and then dump ballast before landing to reduce landing speed and improve handling on approach and touchdown. This matches the described correct statement.

The idea that ballast has no effect on wing loading is incorrect, and the option mentioning release timing without addressing the weight, stall, and cruise effects isn’t a complete description.