PierreB:
My home experiences have highlighted the huge losses of crosswind kites. To be convinced of this, it is sufficient to take a look at the power curves in real time, for example the curves in Figures 15, 17 and 18 which zigzag.
Whether it’s in yo-yo mode, as specified on:
PierreB:
Now, 3 times is also the (low) ratio of the traction force that I measured between the crosswind kite and the parachute kite in the photo above. The traction force is used to determine the power in reeling mode, by multiplying it by the reel-out speed (2/3 of the wind speed to simplify), and then by 4/9 due to the loss of 1/3 of the wind speed by going downwind.
Or in flygen mode , as specified also here .
This topic is about the big losses in crosswind flight traction, due to variable kite velocities. The possible implications on the flygen and yo-yo modes have already been mentioned, with references to support.
On the other hand, it seems to me that rotary devices like Daisy with a good power coefficient (Cp) of around 0.15 , AlphAnemo and The Pyramid experience less or even no such variations due to the tether arrangements making them to work like rotors.