I've never seen an UFO. However, since some TV programs broadcast that UFOs can go into the stopped state within a slit second from high-speed flying and vice versa, and, therefore, I wish to presume their flying principle assuming that the broadcasts are true. Please be aware that there is absolutely no credibility.
As a matter of fact, anyone can experience this way to fly on land. You can experience it but never do it for real. All you have to do is to drive a car at 100km/h on an expressway and crash the car into the center of expressway tollgate. This way, you can halt the car in split seconds. However, naturally, the passengers are killed instantly.
The above experiment proves that all spacemen aboard UFOs must be constantly crashing against the inner flanks of a UFO and such crashes are fatal because the force of such crashes is more than enough to bash up bodies. You need to be immortal to board a UFO.
This means that there must be a gizmo (or device) inside UFO that shuts down the effect of sudden changes in speed.
It may well be the so-called gravity control system.
Let's assume a UFO machine body is put to flight using some kind of propulsion system at an accelerated velocity of . For a moment, may become a hell of a figure and the inner part of the UFO must control gravity countervailing the acceleration .
Two controlling systems are working within UFO, the one for controlling propulsion and the other controlling gravity inside the UFO. However, if gravity could be controlled, it is pointless to have two kinds of control systems. It makes better sense to have the UFO itself fly by controlling gravity.
Let's say if it is possible to create a high-intensity gravitational force outside of the UFO, then the UFO will be pulled toward it, Moreover, because it is the same as free-fall descent it is weightless. By annihilating the gravitational force when UFO flies at high-speed then the UFO continues to fly and the inner part of this UFO is weightless.
But when gravitational source is there, then beside the UFO, air is also congregated. When this gravitational force is annihilated in split seconds, then congregated air is released and, probably, it may sound like an explosion.
However, it is contradictory because UFO flies without making any noise.
As it turns out, UFO's flying principle cannot be explained by today's physics.
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