Hi everybody.
Here are two links I thought you'd be interested in if you you really
want to know about some
Manmade rigid body flying saucers built way back. just Think what we
are capable of building today.
Hehehe.
http://users.chariot.net.au/~theburfs/URskyship.html

http://users.chariot.net.au/~theburfs/URthermo.html
Buoyancy is everything to these projects. Negative weight. Hint hint.
Sorry I just had to say it.
Enjoy and best of luck and happy Holidays.
Jerry.