Dornier Haunebu II

Developed with utmost secrecy during WWII, the Haunebu II was powered by a revolutionary "Gravity Bell" motor, and was the cause of many of the mysterious "Foo-Fighter" sightings by Allied bomber crews. It's devastating weaponry was still being perfected when the war came to an end.

Further versions were planned, but only a single prototype of the Haunedu III Gun Ship was constructed, and it did not ever fly. The Haunebu IV "Colony Ship" was planned for the long range invasion plans (with a special study to investigate it's use for a proposed Lunar Colony), but never was developed beyond paper plans (or was it?)....