Dynamic soaring

Dynamic soaring is a flight technique that extracts energy from wind-speed differences across space to sustain or increase speed without powered propulsion.

Wind gradient: A change in wind speed or direction across distance, often with height. Dynamic soaring gains energy by crossing regions where wind speed differs.
Albatross: A seabird with exceptionally long, narrow wings, adapted for efficient flight over open oceans. Albatrosses use dynamic soaring to travel long distances over the sea with little flapping.
Thermal soaring: A flight technique that uses rising columns of warm air to gain altitude. Unlike thermal soaring, dynamic soaring draws energy from horizontal wind-speed differences.
Dynamic soaring cycle: A repeating flight path that crosses a wind gradient to gain energy and returns for another crossing. The cycle is the basic unit of repeated energy gain in dynamic soaring.
Wind shear: A change in wind velocity over a short distance in the atmosphere. Strong shear creates the velocity differences exploited during each soaring cycle.
Radio-controlled glider: A remotely piloted model aircraft that flies primarily by aerodynamic lift. Skilled pilots use wind gradients to make small gliders accelerate and sustain flight.
Slope soaring: A flight technique that uses air forced upward by terrain to maintain altitude. Slope soaring relies on terrain-driven rising air rather than repeated wind-gradient crossings.
Dynamic soaring over the ocean: Dynamic soaring by seabirds across the wind gradients above the sea surface. The ocean surface creates a boundary layer that albatrosses exploit during low-altitude crossings.
Apparent wind: The airflow experienced by a moving object, combining its motion with the surrounding wind. Crossing wind layers changes the airflow experienced by the glider and its airspeed.
Uncrewed aerial vehicle: An aircraft that operates without a human pilot aboard. Dynamic soaring has been studied as a way to extend endurance without fuel-powered thrust.

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