The Pennsylvania Railroad, legal name The Pennsylvania Railroad Company, also known as the "Pennsy", was an American Class I railroad that was established in 1846 and headquartered in Philadelphia. It was named for the commonwealth in which it was established. At its peak in 1882, the Pennsylvania Railroad was the largest railroad, the largest transportation enterprise, and the largest corporation in the world.
Under the Whyte notation for the classification of steam locomotives, a 2-10-4 locomotive has two leading wheels on one axle, usually in a Bissel truck, ten coupled driving wheels on five axles, and four trailing wheels on two axles, usually in a bogie. These were referred to as the Texas type in most of the United States, the Colorado type on the Burlington Route, and the Selkirk type in Canada.
John Bull is a historic British-built railroad steam locomotive that operated in the United States. It was operated for the first time on September 15, 1831, and became the oldest operable steam locomotive in the world when the Smithsonian Institution ran it under its own steam in 1981. Built by Robert Stephenson and Company, it was initially purchased by and operated for the Camden and Amboy Railroad, the first railroad in New Jersey, which gave it the number 1 and its first name, "Stevens". The C&A used it heavily from 1833 until 1866, when it was removed from active service and placed in storage.
The AAR wheel arrangement system is a method of classifying locomotive wheel arrangements that was developed by the Association of American Railroads. Essentially a simplification of the European UIC classification, it is widely used in North America to describe diesel and electric locomotives. It is not used for steam locomotives,, which use the Whyte notation instead.
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) 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.
In the Whyte notation for classifying the wheel arrangement of steam locomotives, an 0-8-8-0 is a locomotive with two sets of eight driving wheels and neither leading wheels nor trailing wheels. Two sets of driving wheels would give far too long a wheelbase to be mounted in a fixed locomotive frame, so all 0-8-8-0s have been articulated locomotives of the Mallet type, whether simple or compound. In the UIC classification, this arrangement would be, refined to Mallet locomotives, (D)D. The type was sometimes called Angus in North America.
The Pennsylvania Railroad's class H8, H9s and H10s steam locomotives were of the 2-8-0 "Consolidation" type, the last three classes of such built by the railroad. The three classes differed only in cylinder diameter and thus tractive effort, each subsequent class increasing that measurement by an inch. The first H8 was built in 1907 and the last H10 in 1916; within a few years they were replaced on heavy freight assignments by 2-8-2s and 2-10-0. They became the railroad's standard light freight locomotive, replacing all other class H 2-8-0s, and a number remained in service until the end of PRR steam locomotive operation in 1957. 968 class H8 of various subclasses were constructed, along with 274 class H9s and 273 class H10s. A number of H8 locomotives were rebuilt to H9s specification.
The Pennsylvania Railroad's class B6 was its most successful class of switcher locomotive, or as the PRR termed them "shifter". The PRR preferred the 0-6-0 wheel arrangement for larger switchers, whereas on other railroads the 0-8-0 gained preference. The PRR generally used 2-8-0s when larger power was required.
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 B1 comprised 42 electric switcher locomotives built between 1926 and 1935. They were of 0-6-0 wheel arrangement in the Whyte notation with 700 horsepower. As built, the first 28 locomotives in the 1926 order formed semi-permanently coupled pairs grouped in three classes.
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 Trail Blazer was a deluxe all-coach train, inaugurated between New York and Chicago via Pittsburgh, Pennsylvania on 17:25 schedule operated by the Pennsylvania Railroad. The trains departed New York City and Chicago every day at 4:30 pm and 3:00 pm, respectively, and arrived at the destination the next morning. The Trail Blazer was one of the first all-coach trains to provide premium services comparable to a Pullman train. The Trail Blazer name was first used in 1927 for the East St. Louis-Pittsburgh preferred freight VL-6.
The Pennsylvania Railroad (PRR) class A1 was a class of 0-4-0 type steam locomotives.
The Pennsylvania Railroad (PRR) class CC1s consisted of a single experimental 0-8-8-0 steam locomotive built by Baldwin Locomotive Works in 1912. It was assigned road number #3397 and placed in service at the PRR Pitcairn yard in Pitcairn, Pennsylvania, near Pittsburgh. A subsequent class, the CC2s, was constructed after the tests conducted with this locomotive. Finding little advantage to articulated steam locomotives, the PRR scrapped it in 1932.
The PRR C1 was the Pennsylvania Railroad's class of 0-8-0 steam locomotive, used in switching service. The 0-8-0 was common on most railroads, but not on PRR; when the railroad needed bigger motive power, they used the 2-8-0 "Consolidation". The PRR wanted the best motive power to handle the switching chores at rail yards and interchanges, and the C1 class was the heaviest two-cylinder 0-8-0 switcher ever produced. Calculated tractive effort was 76,154 lb, based on 78% MEP with 60% maximum cutoff. All C1s were retired between 1948 and 1953, none being preserved.
The Pennsylvania Railroad's class H6, H6a, and H6b steam locomotives were of the 2-8-0 "Consolidation" freight type, the most numerous class on the railroad with 1,707 units and the second most prolific 2-8-0 class in North America, with the USATC S160 class rostering 88 units more. The three subclasses differed as follows:
The Pennsylvania Railroad's class A5s was the largest class of 0-4-0 steam locomotives. The Pennsylvania Railroad built 47 in its Juniata Shops between 1916–1924. They were all retired by 1957. One is preserved at the Railroad Museum of Pennsylvania.
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.
The Pennsylvania Railroad class HH1s/Y3s are four-cylinder compound articulated locomotives that consisted of only just six examples of ex-Norfolk and Western Railway Y3 class 2-8-8-2 wheel arrangement. These 2-8-8-2 steam locomotives were similar to the Norfolk & Western Class Y3 2-8-8-2s but with some minor PRR Alterations on them, such as the keystone number plate that was mounted centrally on the small smokebox door and had fitted a little shelter known as a "Doghouse" onto the tender of the locomotive.
