The third approach, levitation by the magnetic interaction between an alternating current (AC) coil and the induced currents in a conducting sheet, was proposed by Bachelet in 1912. This suspension, like the permanent magnet suspension, is inherently stable. If the gap between the AC coil and the conducting sheet decreases, the magnetic repulsive force increases, pushing the coil back up to its equilibrium height. If the gap increases, the magnetic force decreases, causing the coil to move downwards to its equilibrium point. The suspension is vertically stable. Side plates can be incorporated in the guideway to make the suspension laterally stable as well.

Although inherently stable, the power losses in the AC coil and guideway are too great for this approach to be practical.

In 1966, Powell and Danby, realizing that the above approaches were not practical, proposed a new concept based on the use of superconducting magnets on the vehicle. They reasoned that superconducting magnets, which can be made very powerful in terms of their magnetic field strength, lightweight, and essentially lossless (except for a small power input to the cryogenic refrigerator), could levitate vehicles that moved along a guideway of conventional room temperature conductors.