Elevated Sky Bus railway in India features composite coach bodies

Designed to accommodate 150 commuters and travel at speeds as high as 100 kmh, Sky Bus railway transit coaches built for India's Konkan Railway (Mumbai, India) by Kineco Pvt. Ltd. (Goa, India) are expected to ease public transportation in congested metro areas. Coaches will have 4m/13.1-ft-wide sliding passenger doors and travel in tandem above existing roadways, suspended beneath an overhead concrete-enclosed railway supported by vertical concrete columns. Inside the track enclosure, electrically powered "bogies" will travel on a patented "floating" track system.

Each 3.4m wide by 9.44m long by 3.05m high (11.2 ft by 40 ft by 10 ft) coach features cradle-type structural design, linked to its bogie by vertical suspenders that pass through the coach and attach at the bottom of a stainless steel "skeleton" of "D" frames, with the flat side of the "D" supporting the floor. The body is 80-mm/3.14-inch thick fiberglass sandwich panels, which are bonded to the steel frame using Plexus structural adhesives (ITW Plexus, Northants, U.K.). Panels are high-density 80 kg/m3 polyurethane foam core enclosed by skins laminated from Advantex glass mat and woven roving (Owens Corning, Mumbai, India) and Mechter 1620 fire-retardant isophthalic polyester resin from Mechemco Industries (Mumbai). While the prototype was hand layed up and vacuum infused, commercial coaches will be built with vacuum infused and pultruded parts. Interior surfaces are finished with decorative vinyl film while the coach exterior is coated with polyurethane paint from E.I. DuPont India Pvt. Ltd. (Haryana, India). Each coach will consume 500 kg/1,110 lb of composites and cost about $100,000, excluding security cameras, air-conditioning, and inflatable emergency escape chute.

The prototype coach was developed in only three months to meet the railway's October 2003 deadline, with assistance from Bombay-based Mozaic Design and the Indian Institute of Technology. Sky Bus begins dynamic trials this month on a 1.6-km/1-mile test-track near Goa. Work could begin on the first commercial route, a 15-km/9.3-mile, $90 million+ line between the two cities of Panaji and Mapusa, in early 2005.