The current speculation among the WW2 aficionados and experts, such as Dr. Joseph P. Farrell, is that the plane that was trotted out briefly for show last week is quite possibly advanced propulsion originating from Die Glocke, also known as The (Nazi) Bell. The Bell Project was headed by SS Gen. Hans Kammler and was considered top priority over all projects, even atomic weapons. It was thought that The Bell technology was the key to Zero Point which would eliminate Germany's dependence on foreign fuels forever, but it also held promise in that it could levitate, making the jump to the Tesla theory and miniaturization technology.
The links below are: A picture of The Bell, an RT video shot by drone showing the frame in which The Bell was placed for experiments; my friend who grew up in communist Poland says it's still there as of earlier this year and also Dr. Farrell's presentation of items brought back from Germany, which far surpassed our own versions. It's a fascinating study of just what certain govts might have been working on for the past 70+ years and worth the watch.