But if we establish the working hypothesis that the UFOs are...

But if we establish the working hypothesis that the UFOs are machines, we also have to assume the following: a) They are not built by human beings.. b) They are flying by means of artificial fields of gravity.. c) They produce high-tension electric charges in order to push the air out of their paths, so it does not start glowing, and strong magnetic fields to influence the ionized air at higher altitudes.