Transbus Program
[4]: 3–8 General Motors (GM) began developing a replacement for its ubiquitous New Look bus in 1964, demonstrating a three-axle, turbine-powered[e] prototype named Rapid Transit eXperimental (RTX) in 1968.
[4]: 4–7 [5] That same year, the National Academy of Sciences (NAS) published a report providing recommendations for buses that would reduce costs and improve ridership.
[3]: 11 GM wrote a letter to United States Department of Transportation Secretary John Volpe in 1971, complaining that it had begun work on the RTX-derived Rapid Transit Series (RTS) to meet the goals of the 1968 NAS report,[1]: 4 but could not start serial production until UMTA changed its low-bid policy to allow federal subsidies for the RTS.
[1]: 4 The American Public Transit Association proposed for each manufacturer to produce 200 preproduction prototypes for evaluation in service, then hold a two-year production moratorium to gather feedback.
[1]: 113 Due to the Rehabilitation Act of 1973, which was passed in September 1973,[1]: 4 the goals of Transbus shifted to allow full accessibility for public transit vehicles, and the candidate designs were modified to incorporate a ramp or a lift.
[c] On May 13, 1975, one of the Flxible prototypes caught fire during testing in Arizona and was destroyed,[9] but no one was injured; at the time, it was carrying two technicians, instruments, and sandbags to simulate a full passenger load.
GM was undeterred and continued development of the RTS, and Herringer soon left UMTA to head the Bay Area Rapid Transit District.
The Transbus Procurement Requirement (TPR) specifications were first promulgated in 1976, but amended numerous times, occasionally in conflict with prior versions.
[1]: 5 AM General filed a lawsuit against the United States Department of Transportation in 1976 over the "exclusionary" specifications in the GM RTS contract awarded by the consortium,[1]: 4 asserting the new ADB specification requirement to qualify for federal subsidies essentially shut them out of the transit bus market altogether;[10] the lawsuit effectively halted all transit bus procurement nationwide.
[1]: 114 [4]: 3–10 [7] In 1978, the San Francisco Municipal Railway ruled out Transbus for its forthcoming procurement of accessible buses, noting the lowered floor and undercarriage would get caught on the city's hills.
[12] The Transbus specification requirement led three transit agencies[d] to request bids for a joint procurement of 530 buses in January 1979.
[16] Each of the three Transbus manufacturers began marketing transit buses in the 1970s, although each of these newer bus designs had a conventional (high) floor and multiple steps in the entryway.
