Rapid Transit Series

The Rapid Transit Series, usually called the RTS, is a long-running family of American city buses that General Motors built under its GMC Truck and Coach Division in Pontiac, Michigan, from 1977. It was GMC's entry in the federal Advanced Design Bus programme, descended from the prototype it had built for the Department of Transportation's Transbus project, and it was meant as an interim step between the high-floor buses that came before and later low-floor designs. Its automobile-like curved body and window panels looked futuristic at the time. The bus came in 30, 35 and 40 foot lengths on a modular design that shared parts between them, and the longest could seat up to 47 passengers. Early buses used six or eight cylinder Detroit Diesel Series 71 two-stroke engines with Allison or ZF automatic transmissions, and later ones used Series 92 and Series 50 engines. General Motors sold the design in 1987 to Motor Coach Industries, from which it passed to Nova Bus and then to Millennium Transit Services, whose collapse after 2012 ended production.