The

Pennsylvania Railroad The Pennsylvania Railroad ( reporting mark PRR), legal name as the Pennsylvania Railroad Company, also known as the "Pennsy," was an American Class I railroad that was established in 1846 and headquartered in Philadelphia, Pennsylvania. At its ...

's class R1 comprised a single prototype

electric locomotive An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or on-board energy storage such as a Battery (electricity), battery or a supercapacitor. Locomotives with on-board fuelled prime mover (locomotive), ...

constructed in 1934 by the

Baldwin Locomotive Works The Baldwin Locomotive Works (BLW) was an American manufacturer of railway locomotives from 1825 to 1951. Originally located in Philadelphia, Pennsylvania, it moved to nearby Eddystone, Pennsylvania, Eddystone in the early 20th century. The com ...

Philadelphia Philadelphia ( ), colloquially referred to as Philly, is the List of municipalities in Pennsylvania, most populous city in the U.S. state of Pennsylvania and the List of United States cities by population, sixth-most populous city in the Unit ...

, Pennsylvania, US, with the electrical equipment by Westinghouse. It was built as a competitor to the GG1 design, but after trials the GG1 was selected for volume production on the basis of its superior tracking and riding qualities; the R1 prototype, however, remained in service. It was numbered 4800 originally, swapped numbers with the victorious GG1 prototype to #4899, but was moved in May 1940 to #4999 to make room for the expanding GG1 fleet. For many years, the R1's regular duties involved hauling the westbound

Broadway Limited The ''Broadway Limited'' was a passenger train operated by the Pennsylvania Railroad (PRR) between New York City and Chicago from 1912 to 1995. It was the Pennsylvania's premier train, competing directly with the New York Central Railroad's '' 2 ...

and returning eastward with a mail and express train. The long rigid wheelbase of the locomotive caused occasional derailments in

Sunnyside Yard Sunnyside Yard is a large coach yard, a railroad yard for passenger cars in the Sunnyside neighborhood of Queens in New York City. The yard is owned by Amtrak and is also used by New Jersey Transit. The Pennsylvania Railroad (PRR) complet ...

and elsewhere. The R1 design had four driven axles in a rigid

locomotive frame A locomotive frame is the structure that forms the backbone of the railway locomotive, giving it strength and supporting the superstructure elements such as a cab, boiler or bodywork. The vast majority of locomotives have had a frame structure ...

, like a steam locomotive. Each was driven by two

traction motor A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric vehicle, electric or hydrogen vehicles, or electric multiple unit trains. Traction (engineering), Traction motors are used in electrically powe ...

s driving the wheels through a quill drive and sprung cups. Each end of the double-ended locomotive has a four-wheel truck to guide the locomotive at speed, giving the R1 a

4-8-4 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels on two axles, eight powered and coupled driving wheels on four axles and four trailing wheels on two axles. The type wa ...

wheel arrangement In rail transport, a wheel arrangement or wheel configuration is a system of classifying the way in which wheels are distributed under a locomotive. Several notations exist to describe the wheel assemblies of a locomotive by type, position, and c ...

in the

Whyte notation The Whyte notation is a classification method for steam locomotives, and some internal combustion locomotives and electric locomotives, by wheel arrangement. It was devised by Frederick Methvan Whyte, and came into use in the early twenti ...

(

AAR The Aare () or Aar () is the main tributary of the High Rhine (its discharge even exceeds that of the latter at their confluence) and the longest river that both rises and ends entirely within Switzerland. Its total length from its source to i ...

: 2-D-2; UIC: 2'Do2'). Besides the R1, the PRR did not build or order any other 4-8-4 locomotives, however the T1 duplex was essentially a 4-8-4 with two sets of driving wheels as a 4-4-4-4. In many respects the design resembled the earlier, lighter P5, but with an extra driving axle and lower axle loads.

References

{{PRR locomotives Baldwin locomotives 4-8-4 locomotives R1 11 kV AC locomotives Experimental locomotives Westinghouse locomotives Individual locomotives of the United States Passenger locomotives Electric locomotives of the United States Unique locomotives Standard-gauge locomotives of the United States Scrapped locomotives Streamlined electric locomotives Railway locomotives introduced in 1934