EMC 1800 hp B-B

Electro-Motive Corporation (later Electro-Motive Division, General Motors) produced five 1800 hp B-B experimental passenger train-hauling Diesel locomotives in 1935; two company-owned demonstrators, #511 and #512, the Baltimore and Ohio Railroad's #50, and two units for the Atchison, Topeka and Santa Fe Railway, Diesel Locomotive #1. In addition, two single power cars and two twin-unit power cars for the Chicago, Burlington and Quincy Railroad's Zephyr streamliners were built to fundamentally the same design, but clad in Budd Company streamlined stainless steel carbodies. These were #9904 Pegasus and #9905 Zephyrus for the Twin Zephyrs, and #9906A/B Silver King/Silver Queen and #9907A/B Silver Knight/Silver Princess for the Denver Zephyrs.

All were the mechanical ancestors to EMD's successful E-units, with identical pairs of 900 hp (670 kW) Winton 201-A Diesel engines, although they ran on AAR type B two-axle trucks instead of the A1A trucks of E-units. When delivered, the units were fitted with shrouding around their trucks, but this did not last long. Bearings on these trucks tended to run hot, leading the Santa Fe to replace them with three axle trucks. All had mechanical issues, as was to be expected of such revolutionary technology. The EMD demonstrators spent considerable time in aluminum paint, substituting for the various other units while modifications were made to them.^[1]

The boxy carbodies of all but the Zephyrs and the Santa Fe "One Spot Twins" were the work of GE's Erie, Pennsylvania works, EMD having not yet developed the ability to produce their own bodywork. The Zephyr units were bodied by Budd, while the Santa Fe pair were bodied by St. Louis Car. Like most boxcabs, all but the Zephyr units initially had control cabs at both ends, a feature that would only rarely be repeated in future North American locomotives, although it would become common elsewhere.

EMC demonstrators 511 and 512

The two EMC demonstrators, numbered 511 and 512, were built in May 1935 to demonstrate the future of passenger Diesel power to potential customers. The boxy bodywork was not what EMC intended to sell, but it was an easy way to demonstrate the power units and hauling capacity, which would not be changed in the future E-units.

They were demonstrated both together and singly; the latter for shorter trains for local and less busy services, the former to replace larger steam locomotives on heavier trains. These units were highly significant in pioneering multiple unit connections which could be quickly connected and disconnected in the field, allowing units to be "lashed up" into more powerful combinations (operated by a single crew) at will, and allowing malfunctioning units to be replaced with fresh units with ease.

EMC #512, painted silver, served as Unit C of ATSF locomotive #1, and helped pull the first regular run of the streamlined, Budd-built Super Chief on May 18, 1937, together with the road's own booster 1A, after the EMC E1 pair 2/2A built for the train burned out some of their traction motors on a record-breaking exhibition run days before.

In 1938, having outlived their usefulness, the two demonstrators were scrapped. Trucks and some other components were re-used for the two NW4 switchers built for the Missouri Pacific Railroad.

Baltimore & Ohio 50

Baltimore and Ohio Railroad #50 was fundamentally identical to demonstrators 511 and 512 when delivered. In this form, it hauled the first Diesel-powered Royal Blue until the introduction of the EA/EB units in 1937.^[2]Template:Source given

Following that, it had a semi-streamlined "shovel nose" applied to one end, and transferred to the B&O-owned Chicago and Alton Railroad to haul the Abraham Lincoln. When the Alton left B&O control in the merger that created the Gulf, Mobile and Ohio Railroad, #50 entered the GM&O roster as #1200. After World War II, the shovel-nose treatment was removed, restoring the unit to its prior boxcab appearance. The locomotive was placed into local freight service until it was retired, upon which it was donated to the Museum of Transportation, St. Louis, Missouri, where it remains.

Santa Fe 1

Atchison, Topeka and Santa Fe Railway #1 was a twin-unit set built by St. Louis Car Company in August 1935 to haul the Santa Fe's new train, the Super Chief, for its first year of operation, from May 12, 1936 until May 18 of the following year.^[3]

The Santa Fe had wanted the new, streamlined designs on the EMC drawing boards that would become the first E-units, but they would not be ready until 1937, so the railroad asked for two locomotives like the EMC demonstrators as proof of concept, letting the railroad gain some experience with Diesel operation before the E-units and the lightweight, streamlined train they would haul were ready. Because they were always run together, in a back-to-back configuration, Santa Fe employees nicknamed the two units the "One Spot Twins" and "Amos & Andy" (after the popular radio situation comedy). Both units shared a common road number, and the operating department considered them a single locomotive. The mechanical department referred to them as Unit A (lead unit) and Unit B (trailing unit). For a time, AT&SF leased EMC demonstrator #512, which became known as Unit C, while serving on the Super Chief.

The Santa Fe did ask for some cosmetic "dressing up" of the locomotives, since they would be hauling a prestige passenger train, and EMC obliged with a treatment by Sterling McDonald's GM styling department, which included large "eyebrow" air intakes at the front of the units and a striking paint scheme: Olive Green with Cobalt Blue and Sarasota Blue stripes separated by pinstripes of Crimson and Tuscan Red. This livery reduced the boxiness of the locomotives and gave them more of a look of speed. The units often ran hot, and the second unit in particular had trouble getting enough air to cool the radiators; likely the carbodies and the styling touches contributed to this problem. A number of vents were added to the roofs in their first year of existence. Both required larger steam generators, and a greater fuel and water supply. The rear cab of unit 1A (soon renumbered unit 1) and both cabs of unit 1B (renumbered unit 1A) were removed, and the space utilized for these improvements.

The Santa Fe was an ideal railroad to be a Dieselization pioneer; its long desert runs in the Southwest made the provision of water supplies for steam locomotives problematic. The 2226.6 mile run that these units were intended to run, covering mountain and desert, was completely unprecedented, and exposed weaknesses in the design. Their working up period extended for about a year before they were introduced into service, during which time modifications were continually made to them.

After the E1s replaced the proof-of-concept #1 in 1937, the Santa Fe began to further modify the two locomotive units.

Unit A remained in passenger service. It was rebuilt as a single-ended locomotive in 1938 with a "bulldog" front end—a very high, raised cab above a snub rounded nose. The locomotive emerged in the Warbonnet paint scheme similar to the E1s. It retained road number 1.^[4] The lead truck was replaced with a drop-equalizer truck of unusual 1B configuration; the lead axle was unpowered, while the two rear axles were powered. Some time later, the trailing truck was replaced in similar fashion. Three-axle trucks used roller bearings, and rode better at speed and were lighter on the track, with a lower axle loading. They also eliminated problems with hot axle bearings and overheated wheels.

When Unit A was rebuilt in 1938, Unit B received the same modifications, along with road number 10, since it was now regarded as a separate locomotive. In 1941 #10 has its cab removed, and became a booster unit numbered 1A. In 1948, AT&SF rebuilt #1A into freight transfer locomotive #2611 running on EMD Blomberg B trucks.^[5]

Both #1 and #2611 went to EMD as trade-ins on E-8m locomotives in 1953. Bth emerged as booster units, numbered 83A and 84A, respectively.

CB&Q 9904, 9905

9904 Pegasus, & 9905 Zephyrus were the original power for the second pair of Twin Zephyrs. Mechanically the same as the previous 1800 hp locomotives, they had stainless steel carbodies built by Budd. Their sloping front and streamlined styling continued the look of earlier Zephyr trainsets. Built to pull a specific carset, they were later pooled and continued in service until the mid 1950s.

CB&Q 9906, 9907

Silver King (9906A), Silver Queen (9906B), Silver Knight (9907A), and Silver Princess (9907B), were the original power for the Denver Zephyr. Each 1800 hp cab (A) unit, repeats of the 9904-9905, was semipermantly attached to a 1200 hp booster (B) unit, for a total of 3,000 hp. Like 9904-9905, they were intended to pull a specific carset, but would later be pooled, and stayed in service until the mid 50s.

Notes

References

• Brasher, Larry E. (2001). The One-Spot Twins. Midwest City, OK: Santa Fe Railway Historical & Modeling Society. ISBN 0-9713320-0-2. 
• Pinkepank, Jerry A. (1973). The Second Diesel Spotter's Guide. Milwaukee, WI: Kalmbach Publishing Co. ISBN 0-89024-026-4. 
• Reed, Robert C. (1975). The Streamline Era. San Marino, CA: Golden West Books. ISBN 0-87095-053-3. OCLC 1339849. 
• Repp, Stan (1980). Super Chief: Train of the Stars. San Marino, CA: Golden West Books. ISBN 0-87095-081-9. 

External links

• Media related to EMC 1800 hp B-B locomotives at Wikimedia Commons