What’s stopping flux-pinning/quantum locking from being used in ‘no-fuel’ spacecraft engines?

If you are switching a super conductor on and off while moving in a circular motion (in a vacuum) can that produce a net force in a direction? (This is how a UFO could work?) When you attach a superconductor to a rotating disc you can make it so it only loses energy when the

Spacecraft from superconductors and the Meissner Effect

So I was wondering/daydreaming the other day if the Meissner Effect could be used somehow to lift a spacecraft on the planet earth. If you google magnetic levitation there is a wikipedia entry that has the formula for lift produced by a magnetic field. https://en.wikipedia.org/wiki/Magnetic_levitation Magnetic materials and systems are able to attract or press