It’s strange that the demonstration video doesn’t demonstrate many of the features touted- steep angle of attack, slow nadir, autonomous operation; we can only presume that the particular line on the ground released near was the target.
Here’s a podcast with the CEO, Star Simpson...
A better answer would have been "I ran the engine at climb-out speeds and loading for 20 minutes, at 90f ambient air temperature, with a heat gun on the cowling reporting temperatures well below the tolerances declared by the resin manufacturer"-
-or, you know, something like that.
The builder says he molds the wave separately. It's also reported that some inflate a series of bladders. Here's a link out to a conversation: Introducing the Scirocco--All Molded, All Carbon Pitcheron - RC Groups