Great for a hybrid electric drone. Us the module to get to altitude then fuel is gone, and eject it for the weight savings. Completely disposable. Perfect for a military project with cubic dollars but a strict mission profile.
Climate change initiatives will kill all military excesses of emissions.
I do say a clever design to address some of the issues if the wankel style rotary engine. This is really no different except valving, and component locations, but still very clever. Not really efficient either, thermally.
Rotaries are too limiting. As soon as it is tooled, then somebody wants more power, and the design is tooling constrained to the dimensions. No stroke or bore tweaks like the piston recip. No valving changes, just so inflexible to application demands.
I designed a wankel style 18 hp from scratch, sourced the components and it ran very well (natural gas), but in the process found why they are so limited in a constantly evolving production environment.
“I often say that when you can measure what you are speaking about,
and express it in numbers, you know something about it; but when you
cannot measure it, when you cannot express it in numbers, your knowledge
is of a meager and unsatisfactory kind.”