I have noticed that many UFO sighting reports, dating back to the 1940s-1950s, mention rotating components on the UFO, such as a rotating ring at the circumference. It would be interesting to look further into possible parallels with Podkletnov's claims about gravity effects of rotating superconductors.
I have posted some material which I consider relevant at:
http://www.hyper.net/ufo/physics.html
http://www.hyper.net/ufo/overview.html
I have posted some material which I consider relevant at:
http://www.hyper.net/ufo/physics.html
http://www.hyper.net/ufo/overview.html