mark1234 said...
The wind is largely parallel to the ground, as it falls back, irrespective of the bar position, it's angle of attack increases. When at the zenith, it's pretty much parallel to the airflow. When on it's tail on the ground, pretty much perpendicular.
This is spot on.
Try to remember the winds angle of attack to the kite changes depending on the kites position in the wind window. If the kite is on or near to the edge of the wind window you can have the bar sheeted in as the kite moves further into the wind window the kite is effectively sheeted in more without you moving the bar so to compensate the bar should be sheeted out.
As the kite moves through the air the apparent wind (vector sum = true wind + head wind) moves round the leading edge, this allows the bar to be sheeted in more. As soon as the kites speed through the air slows down again or stops the apparent wind will move away from the leading edge stalling the kite if you don’t sheet out.
For figure of ‘8’ing the kite the bar can be sheeted in at the top stroke but it must be sheeted out on the bottom stroke.
A lot of windsurfers getting into kitesurfing make this mistake of pulling the bar in to try and get more power where as this has the opposite effect stalling the kite. The correct technique is to push the bar away letting the wind flow across the kite re-establishing power.
Eventually all of this will happen naturally (auto pilot) without thinking about it, for now be a bit of a nurd and think about the physics of it for uninterrupted kitesurfing.
great for a Sunshade with beer on tap 
