Levity propulsion system  https://www.thenakedscientists.com/forum/index.php?topic=76586.0

Levity is 10^36 stronger than gravity. Use levity to generate lifting force is possible.

The ship is a ball shape capacitor, the outside shell is negative charged, carries extra electrons, the inside shell is positive charged, carries less electrons.

A transformer to adjust the voltage to control the lifting force.

Between the surface of the ship and the surface of the earth existing levity F=Ke x pq/R^2, where p is the total lines of sight electron charge on earth surface, q is the total lines of sight electron charge on the ship. Increase the number of electrons on the ship surface will increase levity.

Use the same principle, we can build floating city and flying board.

Levity originally was thought to be a physical force exactly like gravity but pulling in the opposite direction, like the helium in a balloon. As recently as the 19th century, scientists were still arguing about its existence. I proved it using Coulomb's law.