UFO's are known for having the characteristics of high velocity, quick braking systems, being able to change directions and turn abruptly and at high speed, and the fact that there is no engine sound.  These characteristics of UFO's are not possible and cannot be down with the current and most advanced technology, found on planet earth.

The flying saucers are said to "fly by amplifying gravity waves".  The fuel used in these ships contain element 115, ununpentium, which enables the ships to fly at their high speeds and to warp accross the universe.  The ships push the air from underneath with electric charges and use strong magnetic feilds when flying at high altitudes.  The use of magnetic feilds would explain why observers of UFO's remember feeling as if they were being pushed down.

In 1996 NASA began a "Breakthrough Proplusion Physics" program to try and learn more about space travel and hopefully one day acomplish it.  However, for this to happen, ships that do not use rockets have to be invented to withstand the high speeds they will encounter and new forms of energy must be found for the ships to run on.

Although these ideas seem ridiculous and out of  range for our human minds, it may happen that one day humans will overcome this boundry and become "lost in space".  You never know.  These ideas may be reality, and are being tested, secretly by the government.  Maybe the UFO's people observe are just government vehicles being tested.......