I wonder how they control direction of flight?

I think they don't. The clip was made of many short takes, and the bird
appeard to have no real directional control. On-off, a (fixed for
flight) tail setting, and the wind. When the bird is pointed right, you
flap. Otherwise you glide and wait.

Though that's an expensive way to handle RC. I lost a lot of model
rockets that way.

Jose
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