Interesting you say that, I look at a company like Arrival and think fantasy company, they don't show any of their manufacturing processes, instead doing robot dances. However, boom looks to be taking a modern but practical approach to their manufacturing and have a test plane almost ready to fly. Timelines are aggressive but if contend that wouldn't put it in fantasy land.
Test plan will fly with what engine?
Just months ago weren't they hoping to use someone else's engine? and now already they have this?
Rolls Royce dropped them in September, after a 2 years partnership thing.