The central idea for this train originated with General Motors in 1944, (read about it here)and subsequent practical suggestions from railway officers and transportation experts were combined in a four-car Astra Dome train which included an Electro-Motive 2,000-hp. Diesel locomotive, one chair car, one sleeper, one dining car and one observation-lounge car. Electro-Motive engineers of the Pullman-Standard Car Manufacturing Company developed detail engineering designs with the help of GM stylists and built the cars.
The E.- M. 2,000-hp. Diesel locomotive was 71 ft. long and had a loaded weight of 318,000 lb. Each of the cars was 85 ft. long.
The chair car had a weight of 147,000 lb. and a seating capacity of 72, including the Astra Dome.
The dining car had a weight of 160,000 lb. and seating capacity of 52, including 18 in the Astra Dome and 10 in the private dining room. The total refrigeration space supplied in the car was 111 cu. ft., and had ice-making capacity of 225 lbs of ice cubes in 24 hr.
The sleeping car had a weight of 150,000 lb. and passenger capacity of 24 sitting and 20 sleeping, exclusive of 24 seats in the Astra Dome. This car was designed with two three-berth drawing rooms, eight duplex roomettes for single occupancy, and, under the dome, 3 compartments, each with 2 lengthwise lower berths.
The observation car had a weight of 141,000 lb. and seating capacity of 68. The car was designed with a rear main lounge, cocktail lounge, lower bar and Astra Dome.
The total length of the train, including the locomotive, was 411 ft.; car heights, rail to Astra Dome roofs, 15 ft. 6 in.; empty weight, 920,000 lb.; loaded weight, 977,000 lb.; exterior finish, steel and glass, blue and silver; interior finish, metals, wood plastics and fabrics in 37 colors; total passenger capacity, 216.
The exterior of the train was finished with a glistening blue-green on its sides and roof, punctuated by decorative moldings and sheathing below the windows which had a bright, silver finish.
Finally, after the war, General Motors ordered the four-car demonstrator set from Pullman. The all-dome train was delivered in May 1947 and toured the country as the GM "Train of Tomorrow". The consist went on exhibition tours totalling 65,000 miles. After the tour ended in 1950, the Union Pacific purchased the equipment for it's contribution to pool service in the Seattle-Portland run with NP & GN.