Does a soft crosswind kite really maintain its efficiency as the wind speed increases?

[PierreB]

An explanation from @rschmehl that seems plausible:

PhD defense Paul Thedens at TU Delft

Hi @PierreB, this is clearly my field of interest and you can be sure that we will provide continuous results on this topic. But simply speaking now, the higher the flight speed the higher the aerodynamic loading and thus also the deformation of the kite. How this increased deformation affects the resultant aerodynamic force depends on the design of the kite. It is difficult to make a generic statement because there are many superimposing deformation effects. E.g. spanwise bending (anhedral & sw…

I think the stakes can be high. Perhaps some (crosswind) flexible kites can be studied in order to lead to suitable deformation at high wind speed, keeping its efficiency at high wind speed.

The concern is different for my small Sharp rotors (see above) as they are rigid. But surely larger inflatable versions could undergo deformation by high load, which also explains why the power consumption of a Magnus-effect balloon is so high.