Topic 28056                            Aug. 22, 2019       Dave Santos
Limit Conditions of SS Powerkite Turning

kPower continues to test crosswind power arches with SS kites at Dripping Springs, Texas. Its now well confirmed that the NASA Power Wing turns fastest of any standard power kite type, even though conceived by Rogallo and Barish primarily for highest power-to-weight. Two new limit conditions are identified: Overly aggressive turns deform the NPW nose, if not stop operation; and if the crosswind cableway is not rigged wide enough, or is not square enough to the wind, the kite can lock-out at the edge, as the cableway run angles back to windward.

Overall, thousands of prior flight hours are paying off in predicable repeatable action by an almost maximally simple design. Sessions only tend to end with line-break or anchor failure that indicate the serious power. Cheap flimsy experimental rigs get replaced, piece-by-piece, better tuned, with superior materials. As all such tiny bugs are fixed*, the rigs become ready for the world, and third-party expert validation.


* A recent lesson is that a "kite-pro" tri-tether may be rigged as simply as two lark's heads on a stopper knot, IF the secondary load lark's is between the stopper and primary lark's, OR an extra stopper is provided to prevent lark's slippage. Slippage can cut the lark's loop. What keen sport to simplify a low-complexity AWES rig to the lowest possible number of simple components, including knots.

David Barish
Francis M. Rogallo