Locomotives

On North American railroads, a wide variety of diesel locomotives are in use for hauling freight and passenger services, with electric locomotives used on some passenger routes, as well as a very small number of isolated freight lines (not represented in FYM). Locomotives are mainly characterised by their horsepower (HP) rating, and can broadly be divided into small (3000HP and below) and large (above 3000HP). Smaller locomotives are typically used for switching and local freight services, while larger locomotives haul long distance freights. Locomotives are usually owned by a specific railroad company, and typically remain on their "home" railroad. A small number of locomotive leasing companies also exist, mainly offering services to shortline railroads and industrial switching.

Terminology

The words locomotive, loco, engine, and unit can be used interchangeably. The term power is used in a more vague sense to refer to a railroad's fleet of locomotives, and it is common to hear a player asking "do you have any spare power?" when they are running low on engines.

Locomotives in FYM

Each locomotive has a Reporting mark, such as UP 1234, indicating the owning company (UP, the Union Pacific railroad) and the locomotive's individual number. In addition, every locomotive is assigned to one of the 200+ locomotive types represented in FYM, which describe the detailed characteristics of that locomotive. These characteristics are:

• Horsepower (HP): How powerful a locomotive is, often considered in terms of the HP per Ton (HP/T) of a train - a train with a low HP/T will move slowly!
• Tractive Effort (TE): How much pulling power a locomotive has at low speed. This number is higher for heavy locomotives (more grip), and is also generally higher for more modern locomotive types.
• Weight
• Length

Locomotive types in detail

The North American locomotive market has been dominated by two manufacturers, EMD and GE, since the end of the 1960s. An overview of the locomotives from these manufacturers, and others, is given below.

EMD

Electro-Motive Diesel (EMD), formerly the Electro-Motive Division of General Motors, has been producing diesel locomotives since the 1930s. The company's products are usually prefixed by two letters followed by several digits and letters, such as SW1500, MP15DC, GP38, or SD70MAC.

Switchers

The EMD SW (SWitcher) series consists of small locomotives rated at 1500HP or below, with models built from 1939 until the mid 1970s. The MP (Multi Purpose) series extends this to the mid 1980s. As suggested by the "switcher" designation, these locomotives are mainly used for switching duty in yards or industries. The more powerful SW variants and the MP15DC/AC/T types are still in use on Class I railroads, but in dwindling numbers. However, SW locomotives of all types are very commonly found on private industrial switching duties at grain elevators, steel mills, and chemical plants.

Early GP and SD locomotives

The GP (General Purpose) and SD (Special Duty) locomotive families evolved in parallel, with the GP locomotives having 4 axles, while SD units have 6 axles. The early GP7 and GP9 units were incredibly popular, and are commonly found on shortlines and in industrial duties. The GP38 (2000HP), GP40 (3000HP), and SD40 (3000HP) units were similarly popular products, in addition to their "Dash-2" upgrades (GP38-2, GP40-2, SD40-2). These are still present in large numbers on Class I railroads, carrying out most switching and short distance freight work. A large variety of specialised, modified, altered, or upgraded types of these locomotives exist, but their characteristics are broadly similar. Developments into the 1980s and 1990s brought some units above 3000HP, such as GP60s, SD50s, and SD60s; these can also be found on Class I railroads.

Later SD locomotives

In the 1990s, the SD60 and SD70 lines provided more powerful locomotives with around 4000HP, which form the modern mainline fleets of Class I railroads, in addition to GE's competing products. A major change was the introduction of AC traction motors to some models, which led to large increases in the available tractive effort. The more powerful SD80MAC and SD90MAC units did not prove popular with railroads, with the SD90MAC suffering badly from reliability issues.

GE

The General Electric (GE) company has been involved in diesel locomotive manufacture since the late 1930s, but until the last few decades, it did relatively poorly in the North American market, mainly selling its products overseas. Its Dash-8 and Dash-9 lines cemented its place as a provider of mainline locomotives, and it has continued in that role to this day.

Switchers

Early GE switchers are only found in industrial switching. These are mainly referred to by their weight, with the 44-Ton and 77-Ton variants being most common.

Universal Series

Despite being comparable with EMD products such as the SD40-2, GE's Universal Series (e.g. U18B) is not well represented in North American railroad locomotive fleets, even on shortlines. However, such locomotives are commonly found overseas.