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 Union Pacific'sGeneral Electric steam turbine locomotives, circa April 1939 | |||||||||||||||||||||||||||||||
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TheGeneral Electric steam turbine locomotives were twosteam turbine locomotives built byGeneral Electric (GE) forUnion Pacific (UP) in 1938. The two units werestreamlined, 90 feet 10 inches (27.69 m) in length, capable of producing 2,500 horsepower (1,900 kW), and reputedly able to attain speeds of 125 miles per hour (201 km/h). Stylistically, they resembled UP'sPullman-designedM-10003 through M-10006 power units and contemporaryElectro-Motive Corporation (EMC)diesel designs.
The two locomotives were delivered to UP in April 1939, and they completed test runs and participated in a variety of publicity events for the railroad, including the grand opening of theLos Angeles Union Passenger Terminal, the world premiere ofCecil B. DeMille's filmUnion Pacific, and an inspection byPresidentFranklin D. Roosevelt. While the locomotives displayed excellent acceleration and could maintain schedules better thanconventional steam locomotives, they were also unreliable and expensive to maintain. They never entered regular revenue service.
In June 1939, UP returned the locomotives to GE. By December 1941, the railroad had abandoned the project. In 1941, the GE steam turbine locomotives were tested by theNew York Central, and they were operated by theGreat Northern in 1943 during theWorld War II "power crunch" (a lack of sufficient locomotives to sustain regular operations) before being retired from service later that year. They were scrapped before the end of World War II.
Development of the General Electric (GE)steam turbine locomotives began in late 1936, when GE and the Union Pacific (UP) began collaborating on anoil-powered steam turbine-electric design that they termed a "steam-electric locomotive".[1][2] To produce an altogether new type of locomotive, GE hoped to adapt maturesteam turbine technology from maritime and stationary applications for railroad use. Early GE specifications detailed a streamlined shape,2+C-C+2 wheel arrangement, and production of 2,500 horsepower (1,900 kW) and 81,000 pounds-force (360,000 N) of startingtractive effort (the force generated by a locomotive'sprime mover in order to generate motion throughtractive force).[1]
GE had hoped to deliver a prototype steam turbine locomotive to UP in 1937, but none were completed until December 1938, and were delivered for testing in spring 1939.[2][3][4][5] In total, the two prototype locomotives had taken almost two years to complete.[2]
GE's new steam turbine locomotives featured streamlined bodies with an appearance somewhat similar to contemporaryEMC diesel streamliner designs. The GE locomotives had lightweight bodies consisting ofsteel frames covered withrivetedsheet metal, most of which was made ofaluminum.[3][5] They also had elevatedcabs, similar to those of UP'sPullman-designedM-10003 through M-10006, which afforded greater visibility.[2][3][5] The noses were significantly longer than those on the Pullman units, at 9 feet (2.7 m), which afforded safety for operating crews.[3][5] In total, each unit measured 90 feet 10 inches (27.69 m) in length, 10 feet (3.0 m) in width (at the cab), and15 feet3⁄4 inch (4.591 m) in height.[3]
The February 1939 issue ofGeneral Electric Review claimed that each of the steam turbine locomotives could attain speeds of 125 miles per hour (201 km/h) and that they had twice a conventional steam locomotive'sthermal efficiency. The two units built for UP were streamlined and capable of producing 2,500 horsepower (1,900 kW), and had been designed to operate together "elephant style", nose to tail. Fully loaded, each of the two locomotives weighed 548,000 pounds (249,000 kg). Each could produce 86,500 pounds-force (385,000 N) of starting tractive effort, and between 32,000 pounds-force (140,000 N) and 40,500 pounds-force (180,000 N) of continuous tractive effort, depending on the amount of cooling.[3]
Both of the locomotives hadBabcock & Wilcoxwater-tube boilers, as well as specialized Bailey Meter Company equipment designed to automatically fire and regulate the boiler.[2][6] Each boiler regularly operated at 920 °F (493 °C) and 1,500 pounds per square inch (10,000 kPa) to 1,600 pounds per square inch (11,000 kPa), a boiler pressure higher than that of any extant steam locomotive and much higher than contemporary conventional steam locomotives.[5][6][7] The GE locomotives stored enough oil to give them an operating range of 500 miles (800 km) to 700 miles (1,100 km).[6]
The turbines were designed to operate at 12,500rpm and were paired with agenerator set with a 10:1reduction gearing. A twin-armatureDC generator was used to power thetraction motors, while a three-phase, 220-voltAC generator powered auxiliary functions such as traction motor blowers and providinghead-end power. The latter, which provided lighting, heating, andair conditioning topassenger cars, was unusual in 1939 and would not become standard until the 1970s.[6]
Another notable feature wasdynamic brakes, where some (or most) braking is created by running the traction motors in reverse as generators, and then dissipating that electric power in resistors to produce heat. In this case, the heat was generated in the locomotive as opposed to the roof-top open-air coolers on most modern locomotives. The resistors were cooled by water from the steam loop, thus heating it. This allowed the braking energy to be recaptured into motive power, or as it is more typically known, offeredregenerative braking.[6]
The locomotives also used agear ratio of 65:31, as well asdriving wheels with a diameter of 44 inches (1,100 mm) and 36-inch (910 mm)-diameter guide and trailing wheels.[3] Each also had a 2+C-C+2 wheel arrangement, or 4-6-0-0-6-4T inWhyte notation. Although sold to UP together and promoted as a single 5,000-horsepower (3,700 kW) locomotive, the two units were capable of operation independently of each other.[5]
The locomotives were in operation for six months, among the shortest operational careers in recorded railroading.[7] After being completed in December 1938, they were first tested by GE at itsErie, Pennsylvania facility, then road tested onNew York Central tracks between January and March 1939.[2] They were then delivered to UP in April 1939 atOmaha, Nebraska, in time for the 70th anniversary of the completion of thefirst transcontinental railroad in May, and givenroad numbers 1 and 2.[2][5][8] According to UP historians William Kratville and Harold Ranks, the new locomotives were hoped to be the "replacement to steam" and the "successor of diesels".[2] After completing test runs, UP put the locomotives on public display with tour trains, a national tour, and an inspection byPresidentFranklin D. Roosevelt.[5][8] They were present at the grand opening of theLos Angeles Union Passenger Terminal and were on display in Omaha for the world premier ofCecil B. DeMille's filmUnion Pacific on April 28.[2]
During test runs, the locomotives displayed excellent acceleration and an ability to maintain schedules better than conventional steam engines, although they also had serious reliability problems and relatively high maintenance costs.[2][8] On one occasion, the two locomotives failed while hauling a train fromColorado to Omaha, necessitating a 2800-classPacific steam locomotive to pull them along with the rest of the train for the remainder of the journey.[2] The locomotives worked on several routes in a variety of different capacities, including both passenger and perishable freight service, although they never entered regularrevenue service; in June 1939, the railroad returned them to GE inChicago for what UP president W. M. Jeffers called "necessary modification and/or reconstruction".[2][5][8]
While UP retained interest in the concept of steam turbine locomotives for the next two years, in December 1941 it decided to end its agreement with GE.[8][9] Rail transport author Brian Solomon opines that this was due to the development of other types of locomotives, particularly the4-8-8-4 "Big Boy" steam locomotives,EMD E-units, andEMD FT freight diesels, as well as a potential personnel change in the railroad's motive power department in 1939.[8][10]
GE continued to work on its steam turbine locomotives after UP lost interest. In 1941, the New York Central tested them along its Water Level Route inNew York. During the "power crunch" on American railroads caused byWorld War II, in 1943 the steam turbine locomotives were operated by theGreat Northern betweenSpokane andWenatchee, Washington.[8] By that point, they had been repainted a dark gray,[11] and renumbered GE-1 and GE-2.[8][9] According to a number of sources, includingThe Streamliner, they provided satisfactory service for GN.[8] By late 1943, the locomotives were retired from service and returned to GE.[9] They were scrapped before the end of World War II.[5]
The GE steam turbine locomotives were both the first turbine locomotives to be built inNorth America as well as GE's only steam-powered locomotives.[2]
In the words of history professor and authorJeffrey W. Schramm, the locomotives "were the most ambitious and technologically advanced locomotives to have traveled American rails to that point."[7][12] UP historian Alfred Bruce described the design as "one of the most exceptional steam locomotives ever built".[5][8]
UP steam turbine locomotives #1 and #2 have been reproduced inmodel form by Overland Models.[13]
GE steam turbine locomotive.
