In effect, the superconducting magnets behave like extremely powerful and lightweight permanent magnets. As the vehicle moves, its magnets induce currents in the guideway conductors, generating a magnetic repulsive force that levitates the vehicle. The levitation is automatic and inherent as long as the vehicle is moving, and is inherently and passively stable. If the gap between the vehicle and the guideway decreases, the levitation force on the vehicle increases, automatically pushing it away from the guideway.

The simple conducting sheet guideway has a large magnetic drag force because the induced currents in the guideway are comparable to those in the superconducting magnets on the vehicle. While the vehicle magnets are lossless, the induced currents in the normal conductors on the guideway are not, and produce power losses, which result in a magnetic drag force on the vehicle.

Realizing this, Powell and Danby focused on maglev designs that minimize the magnitude of the induced currents in the guideway relative to the superconducting currents in the vehicle magnets. This in turn minimizes the losses in the guideway and the resultant magnetic drag on the vehicle.

In their first maglev design, Danby and Powell proposed having a sequence of simple conductor loops in the guideway, instead of a conducting sheet. For a given magnetic levitation force, this configuration has considerably lower power losses and magnetic drag forces than the simple conducting sheet guideway.

Following their initial design, Powell and Danby then developed even higher performance maglev configurations, as described in the Learning to Levitate.