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The free kite

A kite must necessarily be attached to the ground through a rope. Latch a kite to the ground and let the wind make it rise is exactly like running with the rope in your hand and make the kite rise when there is no wind. The kite is like an airplane and the row is like its motor. Should the rope be released the kite falls or at least glides toward the ground.

If you want a glider to remain in the air thanks to the wind then you must find some special places where the air is rising. Such rising air can be due to zones on the ground overheated by the sun or to wind passing over a hill. These zones are always localized. If you want to stay in the air then you must remain above the zone or glide from one zone toward another zone.

The proposal of this text is to latch a kite not to the ground but to the mass of air below it, where the wind moves differently. That way it would be taken along by the wind just like a hot air balloon. It would stay in the air without touching the ground.

Sailors and meteorologists know that fact: at different heights the air moves differently. Two superposed layers of air move in different directions and with different speeds. Between a few meters above the ground and a few tens of meters the speed of the air is most often very different.

So if an efficient kite is used (say the shape of a glider) and it is latched to a big coarse lightweight mass below it (say a toy beach ball) through a rope of a few tens of meters, the coarse mass will be pulled by its lower layer of air away from the kite. That will make the kite rise and pull the coarse mass upwards. If they rise too much the difference between the air layers will decrease and they will stop rising.

Launched above the sea, where there is always wind and the surface presents no obstacles, such a kite should travel huge distances.

Should the wind slow down, the coarse mass will land and the water yet the kite will stay in the air awaiting the speed of the wind increases back. Probably a kite shape can be designed that can land on the water too. It would land if there is no more wind at all and take off back again afterwards.

In 2015, a comparable proposal was adopted for financing by the NASA:

Eric Brasseur  -  28 October 1998