During a stable-weather day, where should a glider pilot expect to find lift for soaring?

• A. On the upwind side of hills or ridges with moderate winds present.
• B. In the valley behind hills.
• C. Over open water at low altitude.
• D. Directly under cumulus clouds in still air.

Answer: (A)

When the air is stable, the most reliable lift comes from how wind interacts with terrain. As wind flows up and over hills or along ridges, it is forced upward, creating a band of rising air on the windward slope and near the crest. This orographic lift provides a steady source of lift a glider can ride, especially when the winds are moderate. So the best place to expect lift is on the upwind side of hills or ridges where that wind-driven updraft is strongest.

The other scenarios are less dependable on a stable day. Behind hills in a valley can be variable and often non-ascending; lift over open water at low altitude isn’t a consistent source without a specific wind pattern; and being directly under cumulus clouds in still air wouldn’t produce reliable lift, since there needs to be some upward motion in the air to support climbing flight.