The Pioneer Zephyr is a diesel-powered railroad train formed of railroad cars permanently articulated together with Jacobs bogies, built by the Budd Company in 1934 for the Chicago, Burlington and Quincy Railroad (CB&Q), commonly known as the Burlington. The train featured extensive use of stainless steel, was originally named the Zephyr, and was meant as a promotional tool to advertise passenger rail service in the United States. The construction included innovations such as shotwelding (a specialized type of spot welding) to join the stainless steel, and articulation to reduce its weight.

On May 26, 1934 it set a speed record for travel between Denver, Colorado, and Chicago, Illinois, when it made a 1,015-mile (1,633 km) non-stop "Dawn-to-Dusk" dash in 13 hours 5 minutes at an average speed of 77 mph (124 km/h). For one section of the run it reached a speed of 112.5 mph (181 km/h), just short of the then US land speed record of 115 mph (185 km/h). The historic dash inspired two films and the train's nickname, "Silver Streak". (Read more...)