How much weight can a kite lift -- and flying angle and lift and stability

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I liked this table a lot.

Also the SSSL 3m2 that I have been flying is not on the list (not a good kite for KAP), but it flies at >67 degrees and pulls ~5-7 kg in 5 m/s wind. That would be 11-15 lbs in beufort 3 I guess. Flying so high puts it in a separate league for soft kites, and it is cheap and packs very small


Both so high pull and flying angle look to do an exceptional combination. This kite would almost be suitable for a non crosswind AWE yoyo system.

Its true. Though no depower at the moment. The kite collapses quite easily for full depower, but collapse is kind of random wrt handling

What would be the flying angle (from 67 degrees in static flight) during reel-out phase?

Assuming wind speed is 5 m/s, pull in static flight is 60 N, reel-out speed = 5/3 m/s if possible, the pull becoming 26.66 N as the apparent wind becomes 3.33 m/s.

Note: the optimal 1/3 reel-out speed can be difficult to achieve due to the high flying angle, but I can be wrong.

60 N pull leads to lift = 55.4 N and drag = 23.08 N, assuming L/D ratio = 2.4. During reel-out phase the resulting pull of 26.66 N leads to 24.61 N for the lift, assuming the drag value doesn’t change, leading to a L/D ratio of 1.06, roughly 1, so a flying angle of about 45 degrees, and the power of this 3 m² kite would be 26.66 x 3.33 x 4/9 = 39.4 W during reel-out phase, 13.9 W due to cosine-cubed law with 45° elevation (flying) angle.

26.66 N is the resulting pull as the reel-out speed is 1/3, so the apparent wind 2/3 of 5 m/s, lowering the force and power by 4/9.

The problem with producing upwards I touched upon in the Laddermill thread. My conclusion is that energy is produced mostly in downwind direction. The kite would need to loop downwind for real energy production

The intuitive reason is that once you release tether fron the spool/winch, a kite flyibg at zenith will immediately lose most of its power

I experimented a soft kite making small loops on Low radius loop, the force being about 6 times the kite area (power harvesting factor), that is a value close to the maximum value which would be achieved by using a kite of which its area is as large as the swept area by the loop.

The downwind component is the same by using both static (the present lifting kite or Laddermill) and crosswind (small loops or large lemniscates) kites.