Abstract

A rapid transit system in which a vehicle, typically consisting of a train of detachably coupled cars, is suspended in a vacuum tunnel with at least two sloping reaches from a ferromagnetic monorail of high resistivity by magnetic attraction and propelled by gravity. Servo-controlled electromagnets allow the vehicle to be suspended from the rail without actually being in contact with it or any other part of the tunnel. Propulsion by gravity from one station to the next is accomplished by allowing the vehicle to coast frictionlessly down one sloping reach of the tunnel during which time it is automatically accelerated, leveling off at the horizontal reach at some cruising depth where it coasts along at an essentially constant maximum speed, and then moving up the next sloping reach toward the second station during which time it is automatically decelerated, and finally stopping at the station where the original elevation is reached. When moving from one station to another station at a lower elevation, the excess kinetic energy is recovered by regenerative braking and stored in flywheel alternator-motor energy storage units to be used later in electric motors that enable the vehicle to move from one station to another station at a higher elevation, eventually returning to the original elevation.