[wbhart]

I would be more inclined to believe it if it didn't fly out of frame before it had even been in the air as long as the "unsustained" flight. I simply can't imagine why they are so careful to obscure their sustained flight from scrutiny. I think it is healthy to have a measure of scepticism.

[decode]

It is indeed hard to see in the Nature video, but this one has the full flight: https://www.youtube.com/watch?v=a9yYu-ZM1S0