I always question startups like this where multiple breakthroughs are required. In this case it's hypersonic aircraft AND rotating detonation engines. For a 20

I always question startups like this where multiple breakthroughs are required. In this case it's hypersonic aircraft AND rotating detonation engines. For a 20 percent fuel savings they should be able to prove the aircraft concept independently. Either that or a fully usable RDE is a product in itself. Making the company success dependent on both seems a mistake to me.