Closed Cell effect
- One of the behavior that I observed exclusively to closed cell foils
(therefore the name closed cell effect) and that could be the cause of
this drift back.
In both regular foils and closed cell foils, it's the internal pressure
of the air that keep the foils in shape. Since there are many many
opening in regular foils, the internal pressure is almost instantly
changed when the external pressure changes; therefore the kite shape is
In the case of closed cell since there are little connection between the
pressure inside and outside, each time the external pressure changes
suddenly due to sudden gust or wind direction changes, the kite could
get slightly out of shape enough to decrease its L/D and drift back.
I've never been able to see the change in the kite shape (too subtle,
too far, also I am a bit near sighted), but I can definitely see the
drifting back and feel the effect with my handles (the kite is not as
fast and responsive as it normally would).
This effect happens more in gusty powered up conditions.
Dwight & Jacky wrote:
> > Could the drifting back be due to "closed cell" effect? Are your kites
> > the regular EXs or Wave EXs?
> > Hung.
> Wave EXS