 | This article needs additional citations for verification .(October 2013) |
The long hood of a hood unit-style diesel locomotive is, as the name implies, the longer of the two hoods (narrower sections of the locomotive body in front and behind of the cab) on a locomotive, particularly American-type freight locomotives.
The long hood normally contains the diesel engine (prime mover), the main generator or alternator, the locomotive's cooling radiators, the dynamic brake resistor grids if fitted, and most of the locomotive's auxiliary equipment. Head-end power equipment, if fitted, is normally in the long hood; steam generators for heating older passenger cars may be either in the long or short hoods.
Normally, the long hood is the rear of the locomotive. For early hood unit models, this was not the case; railroads preferred to run with the long hood at the front and the cab at the rear (referred to as operating long hood forward or LHF). It is a common misconception that locomotives were run LHF to provide greater protection, although it may have been a secondary benefit. Southern Railway and Norfolk and Western Railway operated their locomotives bidirectionally to make coal shifting more efficient. By putting the engineer on the right side with the Long Hood Forward, the engineer could see signals down the long hood and around the short hood for operations in both directions. [1] Later, preferences changed to having the short hood at the front and the long hood at the rear for better visibility and with the advent of Wide, or Comfort, cabs. Visibility became a deciding factor when more powerful engines required larger, visibility-obscuring radiator units.
The railroads that held out the longest for long-hood leading were the Norfolk and Western Railway and the Southern Railway (later merged into the Norfolk Southern Railway). When Southern Railway received their first EMD GP7s, they were delivered with a high short hood, and Southern Railway pointed the locomotive LHF for crew safety. After the first GP7s hit the Southern Railway System, subsequent locomotives were ordered with the high short hood and the long hood designated (starting after the SD45 order) as the front. Here is a list of each locomotive Southern ordered with a high short hood, and operated LHF.
(note: the SD50 and the GP59 are the first units ordered with the low, short hood, and pointed LHF)
The Norfolk and Western Railway (NW) operated as Southern Railway did, with the long hood toward the front; the only difference between NW locomotives and Southern locomotives was the position of the bell. NW had the bell on the short hood while Southern had the bell on the long hood.
Many early diesel locomotive builders designated the long hood end of their road switchers as the front. Examples include models manufactured by the American Locomotive Company and Baldwin Locomotive Works.
Long hood forward is a fading practice. Most modern locomotives produced in the USA feature wide-nose Canadian comfort cabs with desktop style controls, which bar the ability to operate the unit long hood forward because the desktop style prevents the engineer from turning in his or her chair to face the other end of the locomotive.
The term 'long hood forward' is not used in Britain, as the hood would be described as a "bonnet" or "engine compartment". Most British diesel locomotives have a cab at each end, so the term does not apply. Where a single-cab design was used, it was designed to be operated long hood forward, but, in practice, it might operate in either direction, like a steam tank locomotive. Apart from shunters, the only single-cab class still in service in Britain is the British Rail Class 20. These are now usually operated cab forward (often in pairs) to give the driver a better view of the track ahead, while some have been fitted with nose-mounted video cameras for use when working long hood forward. [ citation needed ]
Philippine National Railways is operating long hood forward on their locomotives on passenger operations depending on what direction the locomotive is facing.
PT Kereta Api Indonesia formerly operated locomotives long hood forward for both passenger & freight operations. It now operates most trains short hood forward for safety reasons, but at least one train still runs long hood forward. [ citation needed ]
The Southern Pacific was an American Class I railroad network that existed from 1865 to 1996 and operated largely in the Western United States. The system was operated by various companies under the names Southern Pacific Railroad, Southern Pacific Company and Southern Pacific Transportation Company.
The EMD BL2 is a model of diesel-electric locomotive built by General Motors Electro-Motive Division (EMD). A total of 59 units were built between 1947 and 1949. The BL2 was not very successful, as it was unreliable and occupied a gap between carbody and hood units which resulted in it suffering from the drawbacks of both designs. However, lessons learned from the BL2 were incorporated into EMD's next design, the GP7.
The EMD GP30 is a 2,250 hp (1,680 kW) four-axle diesel-electric locomotive built by General Motors Electro-Motive Division of La Grange, Illinois between July 1961 and November 1963. A total of 948 units were built for railroads in the United States and Canada, including 40 cabless B units for the Union Pacific Railroad.
A hood unit, in North American railroad terminology, is a body style for diesel and electric locomotives where the body is less than full-width for most of its length and walkways are on the outside. In contrast, a cab unit has a full-width carbody for the length of the locomotive and walkways inside. A hood unit has sufficient visibility to be operated in both directions from a single cab. Also, the locomotive frame is the main load-bearing member, allowing the hood to be non-structural and easily opened or even removed for maintenance.
In North American railroad terminology, a cab unit is a railroad "locomotive" with its own cab and controls.
A road switcher is a type of railroad locomotive designed to both haul railcars in mainline service and shunt them in railroad yards. Both type and term are North American in origin, although similar types have been used elsewhere.
The EMD SD40-2 is a 3,000-horsepower (2,200 kW) C-C diesel-electric locomotive built by EMD from 1972 to 1989.
The EMD DD35A, also known as the EMD DDA35, was a 5,000 hp (3,730 kW) diesel-electric locomotive of D-D wheel arrangement built by General Motors Electro-Motive Division exclusively for the Union Pacific Railroad. They were a cab-equipped variant of the previous, cabless booster EMD DD35. Fifteen DD35A locomotives were built between May and July 1965; they were assigned road numbers 70 through 84. This request also led to the introduction of the ALCO Century 855 and GE U50. A further development of the 8 axle, twin-engined locomotive produced the final, best known type, the DDA40X "Centennial".
The EMD NW5 was a 1,000 hp (750 kW) road switcher diesel-electric locomotive built by General Motors Electro-Motive Division of La Grange, Illinois between December 1946 and February 1947.
The EMD SD24 was a 2,400 hp (1,800 kW) six-axle (C-C) diesel-electric locomotive built by General Motors' Electro-Motive Division of La Grange, Illinois between July 1958 and March 1963. A total of 224 units were built for customers in the United States, comprising 179 regular, cab-equipped locomotives and 45 cabless B units. The latter were built solely for the Union Pacific Railroad.
The EMD SD60 is a 3,800 horsepower (2,800 kW), six-axle diesel-electric locomotive built by General Motors Electro-Motive Division, intended for heavy-duty drag freight or medium-speed freight service. It was introduced in 1984, and production ran until 1995.
The H-24-66, or Train Master, was a diesel-electric railroad locomotive produced by Fairbanks-Morse and its licensee, Canadian Locomotive Company. These six-axle hood unit road switchers were deployed in the United States and Canada during the 1950s.
The EMD GP7 is a four-axle (B-B) diesel-electric locomotive built by General Motors Electro-Motive Division and General Motors Diesel between October 1949 and May 1954.
The EMD GP9 is a four-axle diesel-electric locomotive built by General Motors' Electro-Motive Division between 1954 and 1959. The GP9 succeeded the GP7 as the second model of EMD's General Purpose (GP) line, incorporating a new sixteen-cylinder engine which generated 1,750 horsepower (1.30 MW). This locomotive type was offered both with and without control cabs; locomotives built without control cabs were called GP9B locomotives.
The EMD GP38-2 is an American four-axle diesel-electric locomotive built by General Motors, Electro-Motive Division. Part of the EMD Dash 2 line, the GP38-2 was an upgraded version of the earlier GP38. Power is provided by an EMD 645E 16-cylinder engine, which generates 2,000 horsepower.
An SD9 is a 6-axle diesel locomotive built by General Motors Electro-Motive Division between January 1954 and June 1959. An EMD 567C 16-cylinder engine generated 1,750 horsepower (1.30 MW). Externally similar to its predecessor, the SD7, the SD9 was built with the improved and much more maintainable 567C engine.
The ALCO MRS-1 is a type of diesel-electric locomotive built by the American Locomotive Company for the United States Army Transportation Corps. They were built with multigauge trucks and to a reduced loading gauge for service anywhere in the world in the event of war.
Southern Pacific 9010 is a KM ML 4000 C'C' diesel-hydraulic locomotive, built in 1964 by German manufacturer Krauss-Maffei for the Southern Pacific Railroad. SP 9010 generated 4,000 horsepower (3,000 kW) from two 2,000 horsepower (1,500 kW) V16 Maybach MD870 diesel engines. It was painted to Southern Pacific's 1958 standard, the so-called "bloody nose" colors of Scarlet and Lark Dark Gray, for its entire operating career. It was renumbered to SP 9113 in late 1965, rebuilt extensively at SP's Sacramento General Shops during the latter half of 1966, and was initially retired in 1968. It was revived and rebuilt by Sacramento General Shops into a "camera car" for the purpose of shooting motion picture background plates for a ground-based full-motion locomotive training simulator. As camera car number 8799, it was retired in 1984 and donated to the California State Railroad Museum in Sacramento, California. It was de-accessioned by CSRM and acquired by the Pacific Locomotive Association and moved to the Niles Canyon Railway's Brightside, California rail yard in the summer of 2008. At the date of its inception, its type represented the highest-horsepower six-axle diesel locomotives in the world. SP 9010 is the sole surviving ML 4000 C'C' built for use in North America, and the sole surviving mainline diesel-hydraulic locomotive in North America.
The Krauss-Maffei ML 4000 is a road switcher diesel-hydraulic locomotive, built between 1961 and 1969 by German manufacturer Krauss-Maffei in Munich, Germany. It generated 3,540 horsepower (2,640 kW) from two Maybach V16 engines. 37 examples were built for two North American railroads and one South American railroad.
A B unit, in railroad terminology, is a locomotive unit which does not have a control cab or crew compartment, and must therefore be operated in tandem with another coupled locomotive with a cab. The terms booster unit and cabless are also used. The concept is largely confined to North America. Elsewhere, locomotives without driving cabs are rare.