Paraglider, hang glider, and glider — three different wings, but in the sky they behave the same. Pilots catch invisible warm air currents, rise on them, then glide to the next. Such flight is like a game of hopscotch: a jump upward, then a glide forward, and again a search for a place to jump.
Scientists analyzed thousands of real routes and found a common law. Looking at the distance traveled, it grows slower than in ordinary straight motion. The slowdown coefficient is almost the same for all types of aircraft — about 0.88. This means pilots do not fly in a straight line but constantly veer in search of an updraft. This regime is called 'sub-ballistic': the flight resembles neither a free throw of a stone nor random wandering.
This law unites human soaring flight with the movement of some animals and particles in complex media. Wherever there is an alternation of fast movements and stops for searching, a similar pattern emerges. The air above us is not just emptiness but a field with invisible 'elevators,' and pilots have learned to use them with remarkable precision.
The coefficient 0.88 means that over four hours of flight, a pilot will cover not four times the distance of one hour, but roughly three times. The search for currents 'eats' part of the path.