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Retour au sommaire :         Les turbines Union Pacific

A traduire !

In 1938 General Electric built a pair of steam-turbine-electric locomotives for use on the Union Pacific in an attempt to compete with General Motors passenger diesels. The wheel arrangement of these two locomotives was 2-C+C-2.

Prototype information:

Union Pacific's gas turbine locomotives continue to be among the unique features that make the UP fascinating to the railfan and modeler. At the same time, the period of the turbines' inception and implementation is also a period of management stagnation and even incompetence at the UP. Under the presidency of "Bull" Jeffers and the increasingly detached chairmanship of Averell Harriman, the UP had fallen behind in key areas like dieselization. However, management had even been accused of not building enough steam locomotives to handle World War II traffic. In a corporate political environment, motive power managers were able to cover themselves to some extent by suggesting that gas turbines might prove to be an even better replacement for steam than diesels -- if turbines worked out, their foresight in dragging their feet over dieselization would be justified. Jeffers's successors, the alcoholic George Ashby and his protege A.E.Stoddard, favored turbines apparently without fully understanding the technical issues involved, but regarded the program as an important sign of progress and modernization.

In fact, interest by the UP motive power department in turbines as a possible substitute for diesels had begun prior to 1938. In that year, General Electric delivered two 2500 horsepower steam turbine electric locomotives to UP, numbered 1 and 2. These were intended for high speed passenger service and had styling similar to contemporary diesel units. The units proved a failure on the UP and were returned to GE after less than a year. After World War II, GE resumed development work on a turbine, this time a gas turbine. A demonstrator was completed in 1949, and after test runs on Eastern railroads was sent to the UP, painted and lettered for UP and numbered 50. The demonstrator was generally similar to the first production series, but had a cab at each end.

In March 1951 the UP ordered the first ten production turbines, numbered 51 to 60. The units were rated at 4500 horsepower, the equivalent of a 3-unit set of F7s. It had been found that exhaust modifications performed on the demonstrator prevented double-ended operation, so 51-60 were single ended, with some rearrangement of interior components. Deliveries began in January 1952 and continued to August 1953.

A perceived advantage of turbine power for the UP was the ability to burn relatively cheap Bunker C oil, the same oil as used in oil-burning steam locomotives. However, increases in the cost of Bunker C eventually ended the UP's use of turbines.

In December 1952, UP ordered an additional 15 turbines, with a number of modifications from the first group. The body style somewhat anticipated locomotive designs of 30 years later, with a full-width cab and a narrow engine compartment behind it, accessible by side walkways and engine room doors. The unit's roof was full-width, so that the side walkways resembled verandas, and this led to the nickname of this series of turbines. These units were numbered 61-75, delivered between April and October 1954.

The 25 early production turbines went through a number of modifications. 50-56 were delivered with air intakes on the side, but were converted to rooftop air intakes in 1953. This resulted in a much more cluttered roofline and helps to date early photos of these units. Units 57 and up were delivered with rooftop air intakes. In addition to changes in rooftop details, there were changes to the air filter covers on the sides of the units. For example, early photos of 50-56 show Farr-air filter covers that seem to be close cousins of those on F7s and F9s. Photos of the early units after 1953 show these covers in various stages of removal, and units 57 and up appear to have been delivered with openings in the sides for air intakes, but many of these openings appear to have been blanked out during construction.

Unit 57 was converted to burn propane as an experiment when delivered. It received a propane tank car tender lettered for both the UP and the Richfield Oil Corporation, who were cooperating in the experiment. 57 ran in propane test runs between Las Vegas and Los Angeles from May, 1953 to January, 1954, when it was converted to burn Bunker C oil like the others.

The tender from 4-8-4 #806 was rebuilt for test operation with turbine 61 in October 1955. Following this, tenders for the other 4500 horsepower turbines were made in 1956 by splicing the water compartments from 4-12-2 tenders back to back on a single chassis. The presence of tenders on the 4500 horsepower turbines helps date photos as post-1956. The addition of tenders extended the service range of the 4500 horsepower turbines. Initially, they ran mostly between Ogden and Green River or Cheyenne. After receiving tenders, they ran all the way from Ogden to Council Bluffs.

In late 1955, the UP ordered the final group of gas turbines, the 8500 horsepower "super turbines" in series 1-30. These consisted of two semi-permanently coupled units with a tender. The front unit contained the cab, dynamic brake grids, and an auxiliary diesel; the second unit contained the turbine itself. The tenders, rebuilt by the UP from retired steam locomotive tenders, were added after delivery.

Units 1-30 were delivered between August 1958 and June 1961.

In 1958, most of the 4500 horsepower turbines were modified for multiple-unit operation with diesels. Beginning in 1959, many of the late GP9s were extensively modified, either by applying turbochargers to create "Omaha GP20s" or by applying large fuel tanks to allow them to burn the same Bunker C fuel oil as the gas turbines, or both. It appears that the 1-30 series was always able to multiple with diesels. Multiple unit operation with SD24s was common in 1962.

The 51-75 series 4500 horsepower turbines were withdrawn between April 1962 and June 1964. The reason was increased maintenance costs and mechanical failures. Their trucks and span bolsters were re-used on the GE U50 diesels. The 1-30 series 8500 horsepower super turbines were withdrawn between August 1968 and February 1970. The reason was mechanical failure and the increased price of Bunker C oil.

Equivalent diesel locomotives have lasted 15 to 20 years or more in UP service. An operating life of 10 years or less, as was the case with many UP turbines, was not an indication of success. In retrospect, the UP turbine program probably did not live up to expectations, from an investment or operating perspective. On the other hand, there have been worse mistakes in American railroad history, like the Pennsylvania Railroad/Penn Central Metroliner project, or the Amtrak SDP40F locomotives.

The UP turbines probably were the most successful of any railroad turbine application anywhere in the world, and it probably goes to the credit of a dedicated staff and management that was determined to make the locomotives work.

Certainly for railfans and modelers, the UP turbines have the glamour and appeal of lost causes, second only to steam locomotives.

Model Gas Turbines:

Assez Curieusement, les modeleurs dans l'échelle de N et le fer-blanc O ont eu plus fabriqué en série des modèles de turbine à gaz disponibles que des modeleurs HO. Le modèle de Con Cor N de la 61-75 série mérite la mention pour ceux qui veulent avoir un modèle d'une turbine à gaz, mais ne peuvent pas se permettre un modèle HO de cuivre. Les châssis ont été faits par Kato et le modèle est un plaisir de fonctionner. Le corps et le détail de rampe sont quelque peu durs. Un modèle très populaire de la 1-30 série est disponible dans le fer-blanc O de MTH.

Des importateurs de cuivre ont apporté dans des modèles de turbine HO de cuivre depuis les années 1950, commençant par M.B. Austin. Les modèles tant de la 51-75 que 1-30 série ont été apportés dans par des Modèles Alco et par la suite par Sur terre.

Une injection brute a modelé l'HO-échelle en plastique 51-60 turbine de série a été produite à la fin des années 1980, à une boîte cartonnée non marquée, employant Athearn des composants de commande et des camions. Les numéros(nombres) ont été apparemment très limités. John Bruce (EMAIL : John Bruce@worldrailfans.org), voudrait recevoir des nouvelles de quelqu'un qui sait(connaît) plus de ce modèle. 

Les photos