Well, they have time then. All military VTOL programs (the ones I know of) in the development pipeline are conventional: either helicopters or jet engine powere

Well, they have time then. All military VTOL programs (the ones I know of) in the development pipeline are conventional: either helicopters or jet engine powered (I think the only one here is the F-35). Until the follow-up generation to those comes, this type of engine has around 20 to 30 years of development time left. That being said, this whole idea is too late to the eVTOL start-up craze. Three years ago the animations alone might have been worth 100 million or so.