Reef in a kite???

Are you asking about reducing sail area, or do you mean REEL in a kite?

Kiters reduce area by switching kite sizes just like a windsurfer. They cary an assortment of sizes, big for light wind, small for high wind.
They also have the ability to alter the power of the kite by adjusting it's angle in the sky as well as adjusting it's angle to the wind through the various lines that connect the kite to the control bar.

As far as reeling in the kite, they don't actually reel it in. The lines are a fixed length. So in most instances when the rider is ready to land the kite, they fly it down to ground level and then have a helper grab the kite and hold it on the ground.

The problem is that if the kite overwhelms or "lofts" the rider on the beach, it is very likely that he will lose control of it and it will inadvertantly power up before he can pull any of the emergency quick releases. This is a fundamental safety difference between kitesurfing and windsurfing.

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