[superkuh]

I didn't happen. Look at the video they link. All the forward momentum and lift comes from the launch rail. It simply glides to the ground after that.

[emef]

They noted that the first successful test was at 50% and effectively a power glide. Further in the video you can see they do achieve a sustained flight that reaches the end of the gym and is more than just a glide.

[nsxwolf]

2:56 certainly looks like sustained powered flight to me.

[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