Locomotive classification on the

Pennsylvania Railroad The Pennsylvania Railroad (reporting mark PRR), 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, Pennsylvania. It was named ...

took several forms. Early on,

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 locomot ...

s 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 (the E44) — all

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 or a supercapacitor. Locomotives with on-board fuelled prime movers, such as diesel engines or gas ...

s also used this scheme.

PRR steam and electric classification

A: 0-4-0

Class A was the

0-4-0 Under the Whyte notation for the classification of steam locomotives, represents one of the simplest possible types, that with two axles and four coupled wheels, all of which are driven. The wheels on the earliest four-coupled locomotives were ...

type, an arrangement best suited to small

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 inten ...

s. Most railroads abandoned the 0-4-0 after the 1920s, but the PRR kept it for use on small industrial branches, especially those with street trackage and tight turns. * A1 * A2 * A3 * A4 * A5s * A6

B: 0-6-0

Class B comprised the

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 arrangemen ...

type, the most popular arrangement for

s on the PRR. * B1 * B2 * B3 * B4 * B5 - Rebuilt from class H1 and H2a 2-8-0 * B6 * B7 - Some rebuilt from class H3, H3a, and H3b 2-8-0 * B8 * B21 * B22 * B23 * B28s * B29

C: 0-8-0

Class C was assigned to the

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 ...

type. These were very common on other railroads, but the PRR was not keen on them and only built a few. This was partly because the PRR used

2-8-0 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 no trailing wheels. ...

"Consolidation" types for similar service. * C1 - Largest 2-cylinder 0-8-0 ever built * C29 * C30 * C31

D: 4-4-0

Class D was the

4-4-0 4-4-0 is a locomotive type with a classification that uses the Whyte notation for the classification of steam locomotives by wheel arrangement and represents the arrangement: four leading wheels on two axles (usually in a leading bogie), four po ...

"American" type, the most common arrangement in 19th Century American railroading. 4-4-0s stayed in service on the PRR in secondary work later than on most other railroads, and three were in use until after

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

* D1 * D2 * D3 * D4 * D5 * D6 * D7 * D8 * D9 * D10 * D11 *

D12 D12 (an initialism for The Dirty Dozen) was an American hip hop collective from Detroit, Michigan. Formed in 1996, the group achieved mainstream success with its lineup of ''de facto'' leader Eminem, Proof, Bizarre, Mr. Porter, Kuniva and Swift ...

* D13 * D14 * D15 - Compound * D16 * D21 - ex- Vandalia Railroad, built by Baldwin 1871-1873 * D22 - ex-Vandalia Railroad, built by Pittsburgh 1883-1889 * D23 - ex-Vandalia Railroad, built by Pittsburgh 1884 * D24 - ex-Vandalia Railroad, built by Rogers 1887 * D25 - ex-Vandalia Railroad, built by Pittsburgh 1890 * D26 - ex-Vandalia Railroad, built by Schenectady 1895-1899 * D30 - ex- Toledo, Walhonding Valley and Ohio Railroad, built by Rome 1890 * D31 - ex-Toledo, Walhonding Valley and Ohio Railroad, built 1892-1895 * D32 - Compound, ex-Toledo, Walhonding Valley and Ohio Railroad, built by Baldwin 1892 * D33 * D34 - ex-

Cleveland and Marietta Railroad Cleveland ( ), officially the City of Cleveland, is a city in the U.S. state of Ohio and the county seat of Cuyahoga County. Located in the northeastern part of the state, it is situated along the southern shore of Lake Erie, across the U.S. ...

, built by Rome 1885 * D35 - ex-Cleveland and Marietta Railroad, built by Rome 1885 * D36 - ex-Cleveland and Marietta Railroad, built by Rogers 1885-1886 * D37 - ex-

Cincinnati, Lebanon and Northern Railway The Cincinnati, Lebanon and Northern Railway (CL&N) was a local passenger and freight-carrying railroad in the southwestern part of the U.S. state of Ohio, connecting Cincinnati to Dayton via Lebanon. It was built in the late 19th century to give ...

, built by Baldwin 1894 * D38 - ex-Cincinnati, Lebanon and Northern Railway, built by Pittsburgh 1899 * D39 - ex-

Grand Rapids and Indiana Railroad The Grand Rapids and Indiana Railroad at its height provided passenger and freight railroad services between Cincinnati, Ohio, and the Straits of Mackinac in Michigan, USA. The company was formed on January 18, 1854. Beginnings After grappl ...

, built by Baldwin 1892-1893 * D61 - ex- Cleveland, Akron and Columbus Railway, built by Baldwin 1893 * "Odd D" #10003, an experimental

E: 4-4-2

The 4-4-2 "Atlantic" type was assigned class E. The PRR was an enthusiastic user of the Atlantic type in flatter country, and built some of the most advanced Atlantics used in the United States. * E1 * E2 * E3 * E4 * E5 * E6 * E7 * E21 * E22 * E23 * E28 - Compound * E29 - Compound * "de Glehn" #2512, a single experimental compound locomotive

F: 2-6-0

The

2-6-0 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, six powered and coupled driving wheels on three axles and no trailing wheels. ...

"Mogul" type was assigned class F. On the PRR, this type was used during the period of 1895–1925, approximately. They were mostly used to haul express freight, although some hauled suburban passenger trains. * F1 * F2 - Compound * F3 * F21 * F22 * F23 * F24 * F25 * F26 * F27 * F30 * F31 * F61

G: 4-6-0

* G1 * G2 * G3 * G4 * G5 - Largest 10 wheeler built. PRR constructed 90 for use in commuter service and then built 30 for their subsidiary the Long Island RR. * G53 - Owned By subsidiary Long Island RR

H: 2-8-0

* H1 * H2 * H3 * H4 * H5 * H6 * H8 * H9 * H10

I: 2-10-0

The

2-10-0 Under the Whyte notation for the classification of steam locomotives, 2-10-0 represents the wheel arrangement of two leading wheels on one axle, ten powered and coupled driving wheels on five axles, and no trailing wheels. This arrangement was of ...

"Decapod" type was assigned class I. The PRR only owned one type of Decapod, class I1s, but they owned 598 of them, one of the largest classes of identical power in the United States. * I1s - heavy freight hauler.

J: 2-6-2 and 2-10-4

Class J was first used for two experimental

2-6-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of two leading wheels, six coupled driving wheels and two trailing wheels. This arrangement is commonly called a Prairie. Overview The major ...

"Prairie" locomotives built by

ALCO The American Locomotive Company (often shortened to ALCO, ALCo or Alco) was an American manufacturer of locomotives, diesel generators, steel, and tanks that operated from 1901 to 1969. The company was formed by the merger of seven smaller locomo ...

in 1905. These were both withdrawn from service by the mid-1920s. In 1942, the PRR built 123

2-10-4 Under the Whyte notation for the classification of steam locomotives, a 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 ...

"Texas" type locomotives based on C&O plans; class J now being unoccupied, it was reused for them. The PRR J1 was an improved version of its C&O counterpart with more pulling power. * J1 - 2-10-4 freight locomotives. * J28 - experimental 2-6-2 locomotives.

K: 4-6-2

The PRR assigned class K to the

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 locomotiv ...

"Pacific" type. The Pacific was the most common type of passenger locomotive on the Pennsylvania. * K2 - 153 built at Altoona 1910-1911 * K3s - 30 built by Baldwin in 1913. *

K4s The Pennsylvania Railroad (PRR) K4 4-6-2 "Pacific" (425 built 1914–1928, PRR Altoona, Baldwin) was its premier passenger-hauling steam locomotive from 1914 through the end of steam on the PRR in 1957. Attempts were made to replace the ...

- 425 built by the PRR and Baldwin 1914-1928. * K5 - 2 prototypes built

L: 2-8-2

Class L was assigned to 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 ...

"Mikado" type. * L1s - freight twin to the famed

Pacific (575 built) * L2s - the USRA standard light Mikado (5 built for PRR). * L5 - PRR 2nd generation DC electric locomotive. * L6 - PRR freight AC electric locomotives.

M: 4-8-2

* M1 - mixed-traffic Mountain type, latterly mostly used on fast freight.

N: 2-10-2

* N1s - Lines West heavy freight locomotive. *

N2s The North to Shore Festival (aka North to Shore Arts and Ideas Festival, North to Shore, North2Shore, or N2S) is an annual three-week-long music, comedy, film and technology festival in New Jersey. The event is hosted in June by three New Jerse ...

- USRA Standard 2-10-2, also used on Lines West.

O: 4-4-4

The 4-4-4 arrangement was rare anywhere, and on the PRR it was found only on eight experimental electric locomotives. * O1 - experimental electric locomotives.

P: 4-6-4

The

4-6-4 Under the Whyte notation for the classification of locomotives, represents the wheel arrangement of four leading wheels, six powered and coupled driving wheels and four trailing wheels. In France where the type was first used, it is known as t ...

arrangement was seen on the PRR only on electric locomotives. As a steam locomotive arrangement, it was poorly suited to the PRR's mountainous terrain, wasting much potential adhesive weight on non-driven wheels. That it was so widely used by the rival

New York Central The New York Central Railroad was a railroad primarily operating in the Great Lakes and Mid-Atlantic regions of the United States. The railroad primarily connected greater New York and Boston in the east with Chicago and St. Louis in the Midw ...

would also likely have factored against PRR adoption. * P5 - mixed-traffic electric locomotive, succeeded by the

GG1 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 10 ...

Q: 4-4-6-4 or 4-6-4-4

The Q class comprised what were effectively 4-10-4s with the driving axles split into two driven groups. The Q2 was the most powerful non-

articulated An articulated vehicle is a vehicle which has a permanent or semi-permanent pivot joint in its construction, allowing it to turn more sharply. There are many kinds, from heavy equipment to buses, trams and trains. Steam locomotives were someti ...

steam locomotive ever built and also holds the record for highest horsepower recorded by any steam locomotive at 7,987 hp. * Q1 - experimental duplex freight locomotive. * Q2 - duplex freight locomotive.

R: 4-8-4

The PRR never built any steam locomotives of the

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 w ...

"Northern" type, although the T1 duplexes were effectively a "Northern" with the driving wheels split into two groups. * R1 - experimental electric locomotive, surpassed by the

S: 6-4-4-6 or 6-8-6

Both S class locomotives were originally intended to only have four leading and trailing wheels, but for the S1 increases in weight required an additional axle at each end. In the case of the S2, it was due to wartime limits on the use of advanced steel alloys. * S1 - experimental duplex express passenger locomotive. * S2 - experimental

steam turbine locomotive A steam turbine locomotive is a steam locomotive which transmits steam power to the wheels via a steam turbine. Numerous attempts at this type of locomotive were made, mostly without success. In the 1930s this type of locomotive was seen as a way ...

T: 4-4-4-4

The duplex-drive T1 was the final class of steam locomotive constructed for the Pennsylvania Railroad, and possibly the most controversial. * T1 - Duplex express passenger locomotive.

Compound classifications

The PRR classified

articulated locomotive An articulated locomotive is a steam locomotive (rarely, an electric locomotive) with one or more engine units that can move independent of the main frame. Articulation allows the operation of locomotives that would otherwise be too large to neg ...

s and joined locomotive units by using multiples of the previous classifications. Non-Articulated steam: *

1320 Year 1320 ( MCCCXX) was a leap year starting on Tuesday (link will display the full calendar) of the Julian calendar. Events January–December * January 20 – Duke Wladyslaw Lokietek becomes king of Poland. * April 6 – Th ...

- 2-2-2-0 locomotive, based on the

London and North Western Railway The London and North Western Railway (LNWR, L&NWR) was a British railway company between 1846 and 1922. In the late 19th century, the L&NWR was the largest joint stock company in the United Kingdom. In 1923, it became a constituent of the Lo ...

's Dreadnought Class locomotive. One built.Nock, O. S., et al. Railways at the Turn of the Century, 1895-1905. Blandford P., 1969. Articulated steam: * CC1s -

0-8-8-0 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 ...

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 pressure ...

. Treated as two

s for classification. One built. * CC2s - 0-8-8-0 Mallet locomotive. 10 built.
FG1
- What could have been the PRR's version of the

Norfolk & Western 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 "Precisio ...

class A

2-6-6-4 In the Whyte notation for the classification of steam locomotive wheel arrangement, a 2-6-6-4 is a locomotive with a two-wheel leading truck, two sets of six driving wheels, and a four-wheel trailing truck. All 2-6-6-4s are articulated locomotive ...

simple articulated locomotive. Never built. * HC1s -

2-8-8-0 In the Whyte notation for the classification of steam locomotives by wheel arrangement, a 2-8-8-0 is a locomotive with a two-wheel leading truck, two sets of eight driving wheels, and no trailing truck. These were nicknamed "Bull Mooses". Equival ...

simple articulated locomotive. The PRR's only main-line articulated. One built. * HH1s -

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. Treated for classification purposes as two

s back to back. * HH1 - 2-8-8-2 Norfolk & Western class Y3 borrowed by PRR during

. Articulated electric: * AA1 - experimental 0-4-4-0 or B-B electric locomotives. * BB1 - two-unit prototype AC electric 0-6-0+0-6-0 switching locomotive, later split into single units as class B1. * BB2 - two-unit 0-6-0+0-6-0 DC electric switching locomotives, later split into single units as class B1. * BB3 - two-unit 0-6-0+0-6-0 DC electric switching locomotives for

LIRR The Long Island Rail Road , often abbreviated as the LIRR, is a commuter rail system in the southeastern part of the U.S. state of New York, stretching from Manhattan to the eastern tip of Suffolk County on Long Island. With an average week ...

, later split into single units as class B3. * DD1 - two-unit DC electric locomotive, two

half-locomotives semi-permanently coupled back to back. Served between Manhattan Transfer and

Penn Station Pennsylvania Station is a name applied by the Pennsylvania Railroad to several of its grand passenger terminals. Pennsylvania Station or Penn Station may also refer to Current train stations * Baltimore Penn Station * Pennsylvania Station (Cinci ...

, and to

Sunnyside Yard Sunnyside Yard is a large coach yard, a railroad yard for passenger cars, in Sunnyside, Queens in New York City. Description The yard is owned by Amtrak and is also used by New Jersey Transit. The shared tracks of the Long Island Rail Road (LIR ...

. * DD2 - experimental mixed-traffic AC electric locomotive, similar in overall design and appearance to GG1. * FF1 -

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 wheels. ...

(1-C+C-1) experimental electric locomotive, 1917. Too powerful. * FF2 - 2-6-6-2 motor-generator AC electric locomotives acquired second-hand from the Great Northern Railway (their classes Y1 and Y1a) in 1956. *

- express passenger and freight electric locomotive, highly successful.

Non-standard electric classification

* E2b - experimental B-B

General Electric General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable energ ...

-built AC electric locomotives (3 pairs built). * E3b - experimental B-B-B

Baldwin-Lima-Hamilton The Baldwin Locomotive Works (BLW) was an American manufacturer of railroad locomotives from 1825 to 1951. Originally located in Philadelphia, it moved to nearby Eddystone, Pennsylvania, in the early 20th century. The company was for decades t ...

- Westinghouse AC/DC rectifier locomotives (1 pair built). * E2c - experimental C-C

- Westinghouse AC/DC rectifier locomotives (1 pair built) * E44 - 1960 C-C

AC/DC rectifier freight locomotives. The horsepower-based designation unique to the E44 would be retained and expanded by

Penn Central The Penn Central Transportation Company, commonly abbreviated to Penn Central, was an American Railroad classes, class I railroad that operated from 1968 to 1976. Penn Central combined three traditional corporate rivals (the Pennsylvania Railroad ...

to cover the former

New Haven New Haven is a city in the U.S. state of Connecticut. It is located on New Haven Harbor on the northern shore of Long Island Sound in New Haven County, Connecticut and is part of the New York City metropolitan area. With a population of 134,02 ...

EF4s (E33) and EP5s (E40).

Diesel classification

The Pennsylvania Railroad was slow to dieselize. By the end of WW2 they only had 18 units. However over the next 22 years they had acquired a total of 3005 units. They bought from all the manufacturers: Alco 516 units, Baldwin 643 units, EMD 1,479 units, Fairbanks-Morse 200 units, General Electric 145 units, and Lima 22 units. This diversity was a nightmare for the maintenance department as there was very little compatibility amongst the different builders. ::The class number system is as follows: ::The first letter stood for the manufacturer; A=Alco, B =Baldwin, G =General Electric, E =EMD, F =Fairbanks-Morse, and L =Lima. ::The second and third letters represented the type of service; S =switcher, F =Freight, P =passenger, :: PF=dual service, RS =road-switcher, and H =helper. ::The next number(s) were for horse power rounded to hundreds. ::The last letter, if used, was for model variations.

Alco

Baldwin Locomotive Works

General Electric

EMD

Fairbanks-Morse

References

{{DEFAULTSORT:Prr Locomotive Classification Locomotive classification systems Railway locomotive-related lists