Soaring flight

Soaring flight is flight in which a bird gains or maintains altitude by exploiting rising air currents, often with little or no flapping.

Thermal: A rising column of warm air produced when the ground heats the air above it. Birds circle within thermals to gain altitude without sustained flapping.
Lift (force): The aerodynamic force perpendicular to airflow that helps support an aircraft or animal in flight. Soaring depends on lift balancing weight while rising air supplies extra energy.
Albatross: A seabird in the family Diomedeidae, known for long wings and extensive oceanic flight. Albatrosses are iconic practitioners of dynamic soaring over open water.
Flapping flight: Flight powered by repeated wing strokes that generate lift and thrust. Unlike soaring, it supplies propulsion directly but usually demands more muscular energy.
Orographic lift: The upward deflection of moving air by terrain such as a ridge or mountain. Wind forced over slopes supplies a steady updraft for ridge soaring.
Drag (physics): A force opposing an object's motion through a fluid such as air. Birds must limit drag to make the most of weak or intermittent updrafts.
Vulture: A scavenging bird that feeds mainly on carrion and often searches over broad areas. Many vultures use thermals to search large landscapes while spending little energy.
Powered flight: Flight maintained by an animal's own muscular or mechanical power. Soaring is a form of flight that can reduce reliance on continuous power.
Dynamic soaring: A flight technique that extracts energy from differences in wind speed or direction across adjacent air layers. Albatrosses use wind gradients above the ocean to sustain long flights.
Angle of attack: The angle between a wing's chord line and the oncoming airflow. Changing this angle adjusts lift and drag during circling and transitions between air masses.

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