Budd–Michelin rubber-tired rail cars
| Industry | Railcar manufacturing |
|---|---|
| Founded | 1912 |
| Founder | Edward G. Budd |
| Headquarters | Philadelphia , United States |
| Products | Rubber-tired railcars, stainless steel railcars |
The Budd–Michelin rubber-tired railcars were manufactured by the Budd Company in the United States between 1931 and 1933, drawing inspiration from the French company Michelin's "Micheline" concept. Michelin had introduced its initial railcar in 1929 and, by 1932, operated a fleet of nine vehicles equipped with pioneering pneumatic tire technology. In 1931, a licensing agreement permitted Budd to incorporate Michelin's rubber tires onto its shot-welded, stainless-steel car bodies, facilitating Michelin's expansion into the American market.
Following the production of two prototype units featuring Budd's characteristic semi-streamlined, fluted stainless-steel exterior, Budd constructed four rubber-tired railcars for U.S. railroads: one for the Reading Company, two for the Pennsylvania Railroad, and the Silver Slipper for the Texas and Pacific Railway. These vehicles encountered multiple operational difficulties, including frequent derailments. The Silver Slipper was decommissioned by 1935, while the Pennsylvania Railroad’s pair remained in service until 1948.
Although commercially unsuccessful, the Silver Slipper is occasionally recognized as the "first genuine streamlined passenger train," albeit less prominently than competitors such as the Pioneer Zephyr and Union Pacific's M-10000. Rubber-tired railcars achieved greater acceptance in France and influenced the development of rubber-tyred subway trains utilized in Canada’s Montreal Metro, Mexico City, and several European transit systems.
Design
During the 1920s, the American Budd Company, which was then a relatively small supplier of automobile frames, established a close collaboration with Michelin, a leading French tire manufacturer. Michelin launched its first railcar in 1929 and by 1932 operated nine units fitted with pneumatic tires that enhanced ride smoothness and boosted traction by approximately 35%. The tire system incorporated an aluminum safety ring and flange designed to engage only if tire failure occurred; under normal conditions, only the rubber tire made contact with the rails.
Motivated by Michelin's advancements, Budd sought to integrate these rubber tires with its proprietary shot-welded, stainless-steel car bodies—a fabrication technique developed to overcome structural weaknesses observed in earlier streamlined models such as those produced by McKeen Motor Car Company, which Budd founder Edward G. Budd had previously helped design. Michelin aimed to penetrate the U.S. market through this joint venture. In September 1931, Budd obtained permission to manufacture and promote Michelin’s "Micheline" design within the United States.
Demonstrators
The initial Budd–Michelin project was completed in early 1932: a single-car demonstrator capable of seating 40 passengers, nicknamed the "Green Goose." It featured 12 wheels and was powered by an 85-horsepower Junker diesel engine. A second smaller demonstrator with seating for 30 passengers, called La Fayette, was dispatched to France for evaluation. Both prototypes displayed Budd Company's trademark semi-streamlined, fluted stainless-steel styling.
Production rail cars
Budd manufactured a total of four rubber-tired rail cars for American railroads: one unit for the Reading Company, two for the Pennsylvania Railroad, and the Silver Slipper for the Texas and Pacific Railway. The pneumatic tires were supplied by Goodyear under a Michelin licensing agreement. Beginning in November 1932, Reading operated its 47-passenger vehicle on the New Hope branch line; however, challenges such as a rough ride quality, derailments, limited top speed (approximately 45 mph), and a high cost of $75,000 discouraged additional purchases.
In 1933, Pennsylvania Railroad received two comparable rail cars configured as a motor car with a trailer. These units also experienced issues with their rubber tires, which were eventually replaced by conventional steel-wheeled trucks. Following these modifications, they became the longest-serving Budd–Michelin rubber-tired cars, remaining in service with Pennsylvania until 1943 before a brief stint on Virginia’s Washington and Old Dominion Railroad; both were dismantled by 1948.
Silver Slipper
Delivered in October 1933 to the Texas and Pacific Railway, the Silver Slipper was at that time Budd’s largest rail vehicle, weighing 52 short tons and stretching 140 feet in length. The two-car consist included a power car featuring a distinctive "knife-edge" front end, baggage and mail compartments, standard steel-wheeled trucks, and twin 240 hp American LaFrance gasoline engines coupled with Westinghouse electric generators. The trailing passenger car was equipped with sixteen rubber-tired wheels and accommodated 76 passengers in an air-conditioned interior that included a segregated "Jim Crow" section.
Texas and Pacific intended to deploy the Silver Slipper on the route between Fort Worth and Texarkana; however, it experienced derailment during testing phases. Although the trailing coach was retrofitted with new trucks, persistent mechanical problems plagued the power car. By 1935, the entire Silver Slipper train was scrapped.
Legacy
Historian John H. White characterizes the Silver Slipper as an expensive failure that brought embarrassment to the Budd Company and effectively ended its experiments with rubber-tired rail cars. Despite this setback, Budd quickly redirected efforts toward developing lightweight stainless-steel trains, culminating in the successful production of the Pioneer Zephyr.
Rubber-tired rail vehicles ultimately achieved greater acceptance in France, where Michelin constructed thirty units for the Eastern Railway of France in 1937. Since then, similar rubber-tired subway cars have been adopted by transit systems in Canada, Mexico, as well as various cities across Europe.
Rail historian Brian Solomon points out that the Silver Slipper is occasionally credited as the first genuine streamlined passenger train, despite lacking the widespread media coverage enjoyed by later models. Karl Zimmermann concurs that while the Zephyr and Union Pacific's M-10000 often vie for recognition as the inaugural streamliner, the Silver Slipper deserves acknowledgment within this pioneering category.