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Flight paths are affected by kite size and weight. A minimum turning radius of 4–5
wingspans was identified as a reasonable limit, and a participant commented that the kite
mass limits the ability to turn sharply.
I related a turning radius of 1.5 x wingspan with Vibe 120 cm wingspan, and perhaps a little more with Ozone 1.5 of 180 cm wingspan. I provided a value of “5 to 6 m” where 3 wingspans are 5.4 m, the turning radius remaining at 1.5 x wingspan, perhaps a little more. Both are on Low radius loop topic, where I tried to demonstrate that a maximum power could be achieved with small figures: one reason is that the flight path is more centered in the flight window.
I note that for Daisy the radius of the rotor is about 2.3 blade lengths.
In all these examples we are far from the recommended 4-5 wingspans where a large inner part is not harnessed.
I precise that Vibe and Ozone 1.5 have a L/D ratio of about 4 and a low aspect ratio (for Ozone 1.3 m², 180 cm span, so average 0.72 m cord; similar for Vibe), unlike the proposed flexible kite of 71.7 m wingspan and 514 m² of L/D ratio of 6 and far higher aspect ratio.
I don’t know exactly the behavior of flexible kites as they scale up, but if we keep the proportions and if the behavior is equivalent, the kite of 71.7 m wingspan could have 28.7 m cord, and about 2000 m² area, for L/D ratio of 4 (like Vibe, like Ozone). The turning radius would be 1.5 wingspan. The wind would be more completely harnessed in a smaller space, while the power would be roundly the same (3-4 x more area, 2-3 x less force by L/D ratio). And a fat wing flying slower may be less in demand, but that is not certain. Tests will verify it.
Another point: in page 20, Appendix A. Workshop Participants
Table A1. Participating Organizations in the Airborne Wind Energy Workshop , kPower is mentioned, so Dave Santos. We recognize the remarks he makes about the various limitations due to the mass of the AWES.