The UIC classification of locomotive axle arrangements, sometimes known as the German classification or German system, describes the wheel arrangement of locomotives, multiple units and trams. It is used in much of the world, notable exceptions being the United Kingdom, which uses a slightly simplified form of UIC, and in North America, where the AAR wheel arrangement system is used to describe diesel and electric locomotives. In North America, the Whyte notation is only used for steam locomotives.
The Pennsylvania Railroad GG1 is a class of streamlined electric locomotives built for the Pennsylvania Railroad (PRR), in the northeastern United States. The class was known for its striking art deco shell, its ability to pull trains at up to 100 mph, and its long operating career of almost 50 years.
Locomotive classification on the Pennsylvania Railroad took several forms. Early on, steam locomotives were given single-letter classes. As the 26 letters were quickly assigned, that scheme was abandoned for a more complex system. This was used for all of the PRR's steam locomotives, and — with the exception of the final type bought — all electric locomotives also used this scheme.
The Pennsylvania Railroad (PRR) K4 4-6-2 "Pacific" was its premier passenger-hauling steam locomotive from 1914 through the end of steam on the PRR in 1957.
The M1 was a class of steam locomotive of the Pennsylvania Railroad (PRR). It was a class of heavy mixed-traffic locomotives of the 4-8-2 "Mountain" arrangement, which uses four pairs of driving wheels with a four-wheel guiding truck in front for stability at speed and a two-wheel trailing truck to support the large firebox needed for sustained power. Although built for both passenger and freight work, they spent most of their service lives hauling heavy high-speed freight trains. Many PRR men counted the M1 class locomotives as the best steam locomotives the railroad ever owned.
The Pennsylvania Railroad (PRR) class T1 duplex-drive 4-4-4-4 steam locomotives, introduced in 1942 with two prototypes and later in 1945-1946 with 50 production examples, were the last steam locomotives built for the PRR and arguably its most controversial. They were ambitious, technologically sophisticated, powerful, fast and distinctively streamlined by Raymond Loewy. However, they were also prone to wheelslip both when starting and at speed, in addition to being complicated to maintain and expensive to run. The PRR decided in 1948 to place diesel locomotives on all express passenger trains, leaving unanswered questions as to whether the T1's flaws were solvable, especially taking into account that the two prototypes did not have the problems inherent to the production units.
A 4-4-4-4 steam locomotive, in the Whyte notation for describing locomotive wheel arrangements, has a four-wheel leading truck, two sets of four driving wheels, and a four-wheel trailing truck. While it would be possible to make an articulated locomotive of this arrangement, the only 4-4-4-4s ever built were duplex locomotives—with two sets of cylinders driving two sets of driven wheels in one rigid frame, essentially a 4-8-4 with divided drive.
The PRR S1 class steam locomotive was a single experimental duplex locomotive of the Pennsylvania Railroad. It was designed to demonstrate the advantages of duplex drives espoused by Baldwin Chief Engineer Ralph P. Johnson. It was the longest and heaviest rigid frame reciprocating steam locomotive that was ever built. The streamlined Art Deco styled shell of the locomotive was designed by Raymond Loewy.
The Pennsylvania Railroad's class P5 comprised 92 mixed-traffic electric locomotives constructed 1931–1935 by the PRR, Westinghouse and General Electric. Although the original intention was that they work mainly passenger trains, the success of the GG1 locomotives meant that the P5 class were mostly used on freight. A single survivor, prototype #4700, is at the National Museum of Transportation in St Louis, Missouri.
The Pennsylvania Railroad's class O1 comprised eight experimental boxcab electric locomotives built in 1930 and 1931. They were built in preparation for the New York to Washington Electrification project. They had the wheel arrangement classified as 4-4-4 in the Whyte notation. Although successful, they were not powerful enough for the railroad's increasingly heavy trains. For production, the PRR chose to concentrate on the P5 class, effectively an enlarged and more powerful version of the O1 with an additional pair of driving wheels.
The Pennsylvania Railroad's class DD2 was a single prototype electric locomotive never placed into series production. It was intended as an improved and simplified GG1 for use on the planned, but never built, extension of the PRR's electrification west of Harrisburg, Pennsylvania. The one locomotive produced was numbered #5800 and used in regular Baltimore tunnel helper service until it was scrapped in September 1962.
The Pennsylvania Railroad's class FF1 was an American electric locomotive, a prototype numbered #3931 and nicknamed "Big Liz". It was built in 1917 to haul freight trains across the Allegheny Mountains where the PRR planned to electrify. "Big Liz" proved workable but too powerful for the freight cars of the time with its 4600 available horsepower and astonishing 140,000 lbf (620 kN) of tractive effort. Pulling the train it regularly snapped couplers and when moved to the rear as a pusher its force was sufficient to pop cars in the middle of the train off the tracks.
The Pennsylvania Railroad's class L6 comprised three electric locomotives of 2-8-2 wheel arrangement in the Whyte notation. The intention was to build a whole class of freight boxcab locomotives using this design, but the displacement of class P5a to freight work after the introduction of the GG1 meant that there was little need for more electric freight locomotives.
The Pennsylvania Railroad's class AA1 comprised two experimental electric locomotives constructed in 1905 by the company's own Altoona Works with the assistance of Westinghouse. Intended as testbeds as the PRR began its electrification project, both locomotives remained service into the 1930s.
The Pennsylvania Railroad class Q1, #6130, was a single experimental steam locomotive designed for dual service. The locomotive entered service in 1942, and retired in 1949 after accumulating a relatively low 165,000 service miles.
Class D14 on the Pennsylvania Railroad was a type of steam locomotive with a 4-4-0 wheel arrangement in the Whyte notation. They were originally designated class P in the PRR's pre-1895 classification scheme. Twenty-two locomotives were built at the PRR's Altoona Works ; six in 1893 with 78-inch (1,981 mm) driving wheels, and sixteen in 1894 with 80-inch (2,032 mm) drivers, classified D14a. Later, all sixteen class D14a were rebuilt to class D14b with 68-inch (1,727 mm) drivers for secondary service after they were replaced in top-flight express service, while three of the six class D14 were similarly rebuilt to class D14c.
Pennsylvania Railroad 4800, nicknamed "Old Rivets", is a GG1-class electric locomotive located at the Railroad Museum of Pennsylvania, outside of Strasburg, Pennsylvania in the United States. It is the prototype GG1 and was originally numbered 4899. Built by General Electric in 1934, the locomotive competed against a prototype, the R1, built by rival company Westinghouse. 4800 was kept in service by the Pennsylvania Railroad and its successors, Penn Central and Conrail, until 1979. It was sold the next year to a local chapter of the National Railway Historical Society. 4800 was dedicated in 1982 at the Railroad Museum of Pennsylvania and was designated a Historic Mechanical Engineering Landmark in 1983.
Pennsylvania Railroad 4876 was a GG1-class electric locomotive built in January 1939 at the PRR's Altoona Works in Altoona, Pennsylvania, United States. It is best known for being involved in an accident on January 15, 1953, when the locomotive overran a buffer stop, crashed into the concourse of Union Station in Washington, D.C., and fell partway into the basement after the train's brakes failed. Due to the major crowds expected for the upcoming inauguration of Dwight D. Eisenhower, 4876 was lowered the rest of the way into the basement and a temporary floor was erected overhead. After the inauguration, the locomotive's frame and superstructure was essentially scrapped on site, with all the reusable components shipped back to Altoona, Pennsylvania, to reconstruct a replacement 4876, which operated for another 30 years.
Pennsylvania Railroad 4859 is a GG1-class electric locomotive located in the Harrisburg Transportation Center in Harrisburg in the U.S. state of Pennsylvania. It was operated by the Pennsylvania Railroad and its successors, Penn Central and Conrail. 4859 pulled the first electrically powered train from Philadelphia to Harrisburg on January 15, 1938. It was used in various freight and passenger service until November 22, 1979, when it pulled the last GG1-powered freight train on November 22, 1979. Originally located in Strasburg, it was listed on the National Register of Historic Places in 1982 and was moved to its current location in 1986. It was designated the state electric locomotive of Pennsylvania in 1987 by the Pennsylvania General Assembly and was re-listed on the National Register of Historic Places in 2004.
A duplex locomotive is a steam locomotive that divides the driving force on its wheels by using two pairs of cylinders rigidly mounted to a single locomotive frame; it is not an articulated locomotive. The concept was first used in France in 1863, but was particularly developed in the early 1930s by the Baldwin Locomotive Works, the largest commercial builder of steam locomotives in North America, under the supervision of its then chief engineer, Ralph P. Johnson.
