The USRA standard locomotives and

railroad car A railroad car, railcar ( American and Canadian English), railway wagon, railway carriage, railway truck, railwagon, railcarriage or railtruck (British English and UIC), also called a train car, train wagon, train carriage or train truck, is ...

s were designed by the

United States Railroad Administration The United States Railroad Administration (USRA) was the name of the nationalisation, nationalized railroad system of the United States between December 28, 1917, and March 1, 1920. It was the largest American experiment with nationalization, and ...

, the

nationalized Nationalization (nationalisation in British English) is the process of transforming privately-owned assets into public assets by bringing them under the public ownership of a national government or state. Nationalization usually refers to priv ...

rail system of the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

during

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...

. 1,856

steam locomotive A steam locomotive is a locomotive that provides the force to move itself and other vehicles by means of the expansion of steam. It is fuelled by burning combustible material (usually coal, oil or, rarely, wood) to heat water in the loco ...

s and over 100,000 railroad cars were built to these designs during the USRA's tenure. The locomotive designs in particular were the nearest the American

railroad Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a pre ...

s and locomotive builders ever got to standard locomotive types, and after the USRA was dissolved in 1920 many of the designs were duplicated in number, 3,251 copies being constructed overall. The last steam locomotive built for a

Class I railroad In the United States, railroad carriers are designated as Class I, II, or III, according to annual revenue criteria originally set by the Surface Transportation Board in 1992. With annual adjustments for inflation, the 2019 thresholds were US$5 ...

in the United States, an

0-8-0 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of no leading wheels, eight powered and coupled driving wheels on four axles and no trailing wheels. Locomotives of this type are also referre ...

built by the

Norfolk and Western Railway The Norfolk and Western Railway , commonly called the N&W, was a US class I railroad, formed by more than 200 railroad mergers between 1838 and 1982. It was headquartered in Roanoke, Virginia, for most of its existence. Its motto was "Precisi ...

in 1953, was a USRA design. A total of 97 railroads used USRA or USRA-derived locomotives.

Steam locomotive types

The USRA developed designs for

0-6-0 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles and no trailing wheels. This was the most common wheel arrangement ...

and

switcher A switcher, shunter, yard pilot, switch engine, yard goat, or shifter is a small railroad locomotive used for manoeuvring railroad cars inside a rail yard in a process known as ''switching'' (US) or ''shunting'' (UK). Switchers are not inte ...

2-6-6-2 Under the Whyte notation for the classification of steam locomotives by wheel arrangement, a is a locomotive with one pair of unpowered leading wheels, followed by two sets of three pairs of powered driving wheels and one pair of trailing wh ...

and

2-8-8-2 A 2-8-8-2, in the Whyte notation for describing steam locomotive wheel arrangements, is an articulated locomotive with a two-wheel leading truck, two sets of eight driving wheels, and a two-wheel trailing truck. The equivalent UIC classification ...

Mallet locomotive The Mallet locomotive is a type of articulated steam railway locomotive, invented by the Swiss engineer Anatole Mallet (1837–1919). The front of the locomotive articulated on a bogie. The compound steam system fed steam at boiler pressur ...

s, and both light and heavy versions of the

2-8-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of two leading wheels on one axle, usually in a leading truck, eight powered and coupled driving wheels on four axles and two trailing wheel ...

2-10-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of two leading wheels, ten powered and coupled driving wheels, and two trailing wheels. In the United States of America and elsewhere the is ...

4-6-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels on two axles, six powered and coupled driving wheels on three axles and two trailing wheels on one axle. The loco ...

, and

4-8-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels, eight powered and coupled driving wheels and two trailing wheels. This type of steam locomotive is commonly known ...

types. The light versions were designed with an

axle load An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, bearin ...

of 54,000 lb (24,500 kg) permitting usage on the vast majority of railroads, while the heavy versions were designed to a maximum axle load of 60,000 lb (27,200 kg) for lines with more heavily constructed track. The U.S.R.A. also distributed 2-10-0 Decapods of Russian design to railroads under its control.

USRA 0-6-0

255 of the USRA 0-6-0 design were built, as well as a great many copies.

USRA 0-8-0

175 of the

USRA 0-8-0 The USRA 0-8-0 was a USRA standard class of steam locomotive designed under the control of the United States Railroad Administration, the nationalized railroad system in the United States during World War I. This was the standard heavy switcher o ...

design were built, and it was copied extensively thereafter.

USRA Light 2-8-2 "Mikado"

625 of the USRA Light Mikado type were constructed, making it the most populous USRA type.

USRA Heavy 2-8-2 "Mikado"

233 of the USRA Heavy Mikados were built.

USRA Light 2-10-2 "Santa Fe"

94 USRA Light Santa Fe locomotives were constructed.

USRA Heavy 2-10-2 "Santa Fe"

175 USRA Heavy Santa Fe locomotives were built.

USRA Light 4-6-2 "Pacific"

81 USRA Light Pacifics were constructed.

USRA Heavy 4-6-2 "Pacific"

USRA Heavy Pacific The USRA Heavy Pacific was a USRA standard class of steam locomotive designed under the control of the United States Railroad Administration, the nationalized railroad system in the United States during World War I. This was the standard heavy pass ...

s were built.

USRA Light 4-8-2 "Mountain"

47 of the USRA Light Mountain type were built.

USRA Heavy 4-8-2 "Mountain"

USRA Heavy Mountain The USRA Heavy Mountain was a USRA standard class of steam locomotive designed under the control of the United States Railroad Administration, the nationalized railroad system in the United States during World War I. This was the standard light ...

s were constructed.

2-6-6-2

30 of the USRA 2-6-6-2 type were built.

2-8-8-2

106 of the

USRA 2-8-8-2 The USRA 2-8-8-2 was a USRA standard class of steam locomotive designed under the control of the United States Railroad Administration, the nationalized railroad system in the United States during World War I. These locomotives were of 2-8-8-2 whe ...

locomotives were constructed. The

, in particular, continued building this type after the USRA period, developing and modernising it over time, as its Class Y. A N&W Y6B was the last conventional freight-hauling steam locomotive built in the United States.

Freight cars

As part of the USRA, two common

boxcar A boxcar is the North American (AAR) term for a railroad car that is enclosed and generally used to carry freight. The boxcar, while not the simplest freight car design, is considered one of the most versatile since it can carry most ...

designs were developed: a single sheathed car and a double sheathed car. When the USRA boxcars were being designed there wasn't an industry consensus on which was better, so both were built. Freight car design was still in flux in the early part of the 20th century. As John White points out in ''The American Freight Car'', most cars were really composites, not completely

wood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of ligni ...

or steel, and even after steel cars had become the norm, wood had its uses and advantages. Still, steel

underframe An underframe is a framework of wood or metal carrying the main body structure of a railway vehicle, such as a locomotive, carriage or wagon. See also * Chassis * Headstock * Locomotive bed * Locomotive frame A locomotive frame is the str ...

s had come to replace wood underframes, but as

metallurgy Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the sci ...

improved, there were new designs developed that took advantage of the improved technology. USRA double sheathed boxcars had a fishbelly underframe while the USRA single sheathed cars did not. In general, double sheathed boxcars are like

girder bridge A girder bridge is a bridge that uses girders as the means of supporting its deck. The two most common types of modern steel girder bridges are plate and box. The term "girder" is often used interchangeably with "beam" in reference to bridge de ...

s, so all the support needs to come from the frame. Those cars need a stronger frame, hence the fishbelly underframe. Single sheathed cars are like

truss bridge A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements, usually forming triangular units. The connected elements (typically straight) may be stressed from tension, compression, or ...

s, with the metal side bracing acting as the main structural support for the "bridge." While some engineers did not trust the steel bracing to support a single sheathed car and ordered fishbelly frames for strength, others valued the savings in weight and ordered cars with simpler frames like the USRA SS design.

References

{{DEFAULTSORT:Usra Standard Rolling stock of the United States