Petar Bosnic Petrus describes the way that he thinks an anti gravitational machine could work. He uses terms which allow for a better understanding of the forces involved. Details and drawings are supplied of a theoretical machine. His machine is very similar to the one I am constructing. Both have magnetically floating or levitating rotors, which are electrically driven. His is about 1.2M diameter, around half the diameter of mine. He believes the rotational velocity required would be much higher than what I think to be the case, and we are in agreement that the machine would require 2 counter rotating rotors to negate unwanted craft spin.