SkyTran is a patented Personal Rapid Transit system first proposed by inventor Douglas Malewicki in 1990, and under development by UniModal Transport Solutions Inc. The idea proposes to use light-weight, two-passenger vehicles suspended from elevated passive magnetic levitation tracks. Malewicki predicts SkyTran could operate at speeds of up to 100 miles per hour. No prototype of the SkyTran system has been built, though Inductrack, the proposed magnetic levitation system for SkyTran, has been tested by General Atomics with a full scale model.
Critics of SkyTran say there are no known independent engineering analyses of the project, that Malewicki has no experience building large-scale civil engineering projects, and that UniModal has yet to produce any test projects nor signed any contracts to build the system. Malewicki has blamed the project stalling on his distaste for the bureaucracy of government grant applications.
The proposed system would use Inductrack passive magnetic levitation system. Passive maglev requires no direct power to levitate vehicles - rather, the lift is caused by the movement of the vehicle over the coiled wire in the track. The system is intended to have few moving parts, the main ones being the pod itself, its parking-wheels and door, and fans in heating and air conditioning units. The promoters refer to the system as "solid state."
Malewicki proposes a 3D grid design that avoids intersections by allowing tracks to cross above or below each other. Tracks would be mounted on poles about 30 feet above the ground and would be made of modular steel components, attached to cemented foundations.
Once Malewicki and his partners began making proposals to transit systems, these proposals and their other efforts to publicize the idea began to be described in popular technology magazine and local and national news articles.
The 2008 energy shortages have stimulated interest in many Green vehicle proposals, including SkyTran. The cover of Popular Science Magazine June, 2008 special issue on "The Future of the Environment", featured a SkyTran vehicle prominently in an artist's conception of a future energy-efficient city. "Maglev SkyTran" is one of the transportation proposals in the "Green Mega-City" plan, and its online version included animations that present several SkyTran and Personal Rapid Transit ideas, such as passengers exiting and boarding at off-line elevated "portal" stops while high-speed traffic continues to speed by on its main line.