Flex-Stop (no longer used)
When spreaders flex, kites mush rather than climb in response to control inputs. Also, if allowed to bend, spreaders are liable to snap. However, on small kites destined for certain static applications, a strong yet flexible fiberglass spreader can be useful for un-manned, tethered flying in a wide range of winds.
This was a small fin sewn into the center sleeve with a neoprene or rubber loop for securing the spreader strut. It was used on high nose angle designs to prevent the buckling of relatively long spreaders under load. After the change to carbon fiber spreaders it became redundant, but may still be found on older kites.
Several of the designs have a double-walled fin that partially inflates in normal flight. It pops open as shown, forming a sort of windsock when the kite's nose drops. This action stops dives.
Being double sided, this fin is also twice as heavy. This lowers the center-of-gravity, which increases stability and allows the use of a lighter center spine.
Also, when inflated, these fins don't force the center spine into a straight line like a normal fin. Instead, the ballooning action allows the center spine to curve, which gives a good handling, stable kite that doesn't loose height when line is let out.
The Shifter fin, formerly an option on Wildcards, was more than simply a chopped-off regular fin. It was designed with calculated, dedicated adjustment extremes logically set at conservative fore and aft limits of stability for the particular wing. Unfortunately many owners, when asked how they were getting along with it, answered that they left the ring set at the position had put it... Now, I only attached the rings with a view to keeping them tucked under the bridles when I rolled the kites up. There was no attempt at adjustment, precise or otherwise—I just didn't want the rings to fall off in the packaging. They were also quite time-consuming to make well.
As each kite is built, both halves are assembled on top of each other and kept as flat and evenly tensioned as possible. Splices are pinned down and glued individually. The two wing halves are cut as one, then marked for sewing on both sides (again, with the halves equally tensioned). By the time the sewing is finished, the two wing halves should be exactly symmetrical - it only takes a small discrepancy to cause a kite to pull to one side.Even with perfectly symmetrical wing halves, deltas need each and every pair of wing spars to match, or else they still might not fly right! Whenever there's enough breeze to flex the wing spars there'll be more wind force on one wing than on the other, tending to tip the kite over.
©1998-2020 Dan Leigh, 54 Osborne Road, Pontypool, Gwent, Wales, UK NP4 6LX