Long hood
Encyclopedia
The long hood of a hood unit
-style diesel locomotive
is, as the name implies, the longer of the two hood
s (narrower sections of the locomotive body in front and behind of the cab) on a locomotive.
(prime mover
), the main generator
or alternator
, the locomotive's cooling radiator
s, 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 generator
s for heating older passenger cars may be either in the long or short hood
s.
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), as in a steam locomotive
; this followed crew preference for greater protection in a collision. Later, preferences changed to having the short hood at the front and the long hood at the rear for better visibility, especially 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.
General Motors Electro-Motive Division
(note: the SD50 and the GP59 are the first units ordered with the low, short hood, and pointed LHF)
General Electric Transportation Systems
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.
It should also be noted that 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.
. 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.
Hood unit
A hood unit, in railroad terminology, is a body style for diesel and electric locomotives. On a hood unit, the body of the locomotive is less than full-width for most of the locomotive's length, with walkways on the outside of the locomotive. In contrast, a cab unit has a full-width carbody for...
-style diesel locomotive
Diesel locomotive
A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...
is, as the name implies, the longer of the two hood
Hood (vehicle)
The hood or bonnet is the hinged cover over the engine of motor vehicles that allows access to the engine compartment for maintenance and repair. In British terminology, hood refers to a fabric cover over the passenger compartment of the car...
s (narrower sections of the locomotive body in front and behind of the cab) on a locomotive.
Equipment
The long hood normally contains the diesel engineDiesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
(prime mover
Prime mover (locomotive)
In engineering, a prime mover is an engine that converts fuel to useful work. In locomotives, the prime mover is thus the source of power for its propulsion. The term is generally used when discussing any locomotive powered by an internal combustion engine...
), the main generator
Electrical generator
In electricity generation, an electric generator is a device that converts mechanical energy to electrical energy. A generator forces electric charge to flow through an external electrical circuit. It is analogous to a water pump, which causes water to flow...
or alternator
Alternator
An alternator is an electromechanical device that converts mechanical energy to electrical energy in the form of alternating current.Most alternators use a rotating magnetic field but linear alternators are occasionally used...
, the locomotive's cooling radiator
Radiator
Radiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating. The majority of radiators are constructed to function in automobiles, buildings, and electronics...
s, 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 generator
Steam generator (railroad)
Steam generator is the term used to describe a type of boiler used to produce steam for climate control and potable water heating in railroad passenger cars...
s for heating older passenger cars may be either in the long or short hood
Short hood
The short hood of a hood unit-style diesel locomotive is, as the name implies, the shorter of the two hoods on a locomotive...
s.
Operating direction
Normally, the long hood is the rear of the locomotive. For early hood unitHood unit
A hood unit, in railroad terminology, is a body style for diesel and electric locomotives. On a hood unit, the body of the locomotive is less than full-width for most of the locomotive's length, with walkways on the outside of the locomotive. In contrast, a cab unit has a full-width carbody for...
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), as in a steam locomotive
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...
; this followed crew preference for greater protection in a collision. Later, preferences changed to having the short hood at the front and the long hood at the rear for better visibility, especially when more powerful engines required larger, visibility-obscuring radiator units.
United States
Norfolk and Western Railway
The Norfolk and Western Railway , a US class I railroad, was formed by more than 200 railroad mergers between 1838 and 1982. It had headquarters in Roanoke, Virginia for most of its 150 year existence....
and the Southern Railway
Southern Railway (US)
The Southern Railway is a former United States railroad. It was the product of nearly 150 predecessor lines that were combined, reorganized and recombined beginning in the 1830s, formally becoming the Southern Railway in 1894...
(later merged into the Norfolk Southern Railway
Norfolk Southern Railway
The Norfolk Southern Railway is a Class I railroad in the United States, owned by the Norfolk Southern Corporation. With headquarters in Norfolk, Virginia, the company operates 21,500 route miles in 22 eastern states, the District of Columbia and the province of Ontario, Canada...
). 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.
General Motors Electro-Motive Division
- GP7EMD GP7The EMD GP7 is a four-axle diesel-electric locomotive built by General Motors Electro-Motive Division and General Motors Diesel between October, 1949 and May, 1954. Power was provided by an EMD 567B 16-cylinder engine which generated . The GP7 was offered both with and without control cabs, and...
, - GP9EMD GP9An EMD GP9 is a four-axle diesel locomotive built by General Motors' Electro-Motive Division in the United States, and General Motors Diesel in Canada between January, 1954, and August, 1963. US production ended in December, 1959, while an additional thirteen units were built in Canada, including...
, - GP18EMD GP18An EMD GP18 is a 4-axle diesel locomotive built by General Motors Electro-Motive Division between December 1959 and November 1963. Power was provided by an EMD 567D1 16-cylinder engine which generated...
, - GP38EMD GP38An EMD GP38 is a 4-axle diesel locomotive built by General Motors Electro-Motive Division between January 1966 and December 1971. Power was provided by an EMD 645 16-cylinder engine which generated ....
, - GP38-2EMD GP38-2An EMD GP38-2 is a four-axle diesel-electric locomotive of the road switcher type 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...
, - GP40XEMD GP40XAn EMD GP40X is a 4-axle diesel locomotive built by General Motors Electro-Motive Division between 1977 and 1978. Power for this unit was provided by a turbocharged 16-cylinder EMD 645F which could produce 3,500 horsepower . 23 examples of this locomotive were built for North American railroads...
(SOU 7000-7002), - GP49EMD GP49An EMD GP49 is a 4-axle diesel locomotive built by General Motors Electro-Motive Division. Power was provided by an EMD 645F3B 12-cylinder engine which generated 2800 horsepower . The GP49 was marketed as one of four models in the 50 series introduced in 1979. The 50 series includes GP/SD49 and...
(SOU 4600-4605), - GP50EMD GP50* Sarberenyi, Robert. ...
(SOU 7003-7092), - SD7EMD SD7An EMD SD7 is a 6-axle diesel locomotive built by General Motors Electro-Motive Division between February 1952 and November 1953. Power was provided by an EMD 567B 16-cylinder engine which generated ....
, - SD9EMD SD9An EMD SD9 is a 6-axle diesel locomotive built by General Motors Electro-Motive Division between January 1954 and June 1959. Power was provided by an EMD 567C 16-cylinder engine which generated . This model is, externally, similar to its predecessor, the SD7. The principal spotting feature are the...
, - SD35EMD SD35An EMD SD35 is a 6-axle diesel locomotive built by General Motors Electro-Motive Division between June 1964 and January 1966. Power was provided by an EMD 567D3A 16-cylinder engine which generated . A fuel tank was used on this unit. This locomotive model shared a common frame with the EMD SD28,...
, - SD40EMD SD40The EMD SD40 is a 6-axle diesel locomotive built by General Motors Electro-Motive Division between January 1966 and August 1972.-Design:Like its predecessor in EMD's catalog, the SD35, the SD40 is a high-horsepower, six-motor freight locomotive....
, - SD40-2EMD SD40-2The EMD SD40-2 is a C-C locomotive produced by EMD from 1972 to 1989.The SD40-2 was first introduced in January 1972 as the mid-range offering in EMD's six-axle "Dash-2" series, competing against the GE U30C and the MLW M630...
, - SD45EMD SD45The EMD SD45 is a six-axle diesel locomotive built by General Motors Electro-Motive Division between December, 1965, and December, 1971. Power was provided by an EMD 645E3 twenty-cylinder engine which generated 3,600 HP. This locomotive shared the same common frame with the EMD SD38, EMD SD39, EMD...
(note: the SD50 and the GP59 are the first units ordered with the low, short hood, and pointed LHF)
General Electric Transportation Systems
GE Transportation Systems
GE Transportation, formerly known as GE Rail, is a division of General Electric. The organization manufactures equipment for the railroad, marine, mining, drilling and energy generation industries. It is based in Erie, Pennsylvania. Locomotives are assembled at the Erie plant, while engine...
- B30-7GE B30-7The GE B30-7 diesel locomotive model was offered first by GE in 1977, featuring a 16 cylinder motor. It is 61 ft 2 in long. A change to the original B30-7 was using the 12 cylinder FDL rated at 3000 horsepower, resulting in a B30-7A, B30-7A1 and a cabless B30-7A .B30-7As were built...
, - U23BGE U23BThe GE U23B Diesel-electric locomotive was introduced by GE Transportation in 1968 as a medium horsepower roadswitcher, featuring a 12 cylinder FDL engine. It was one of the most successful models of the Universal Series, with railroads ordering it from 1968 until 1977 when it was replaced by the...
, - B23-7GE B23-7The GE B23-7 is a diesel locomotive model that was offered first by GE in 1977, featuring a 12 cylinder engine. It is 61 ft 2 in long. It competed with the EMD GP38-2. General Electric also produced a variant, the BQ23-7, for the Seaboard Coast Line.Ten Ferrocarriles Nacionales de México...
, - U30CGE U30CThe GE U30C was one of the earliest successes from General Electric in the diesel locomotive market. With 600 units sold, the U30C proved to be a choice for customers who weren't able to purchase SD40's or SD40-2's from EMD due to mass orders...
, - U30BGE U30BGeneral Electric's U30B was a further development of the U28B locomotive, with a 3000 horsepower 16-cylinder prime mover. It remained in production for over eight years. The U30B competed with the EMD GP40 and the ALCO Century 430, but was not as successful at the GE U30C.-External links:*...
, - U33CGE U33CThe GE U33C is a 6-axle diesel locomotive built by GE Transportation Systems between 1968 and 1975. 375 examples of this locomotive were built for North American railroads.-Original Owners:-External links:* Thompson, J. David. ....
,
The Norfolk and Western Railway
Norfolk and Western Railway
The Norfolk and Western Railway , a US class I railroad, was formed by more than 200 railroad mergers between 1838 and 1982. It had headquarters in Roanoke, Virginia for most of its 150 year existence....
(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.
It should also be noted that many early diesel locomotive builders designated the long hood end of their road switchers
Switcher
A switcher or shunter is a small railroad locomotive intended not for moving trains over long distances but rather for assembling trains ready for a road locomotive to take over, disassembling a train that has been...
as the front. Examples include models manufactured by the American Locomotive Company
American Locomotive Company
The American Locomotive Company, often shortened to ALCO or Alco , was a builder of railroad locomotives in the United States.-Early history:...
and Baldwin Locomotive Works
Baldwin Locomotive Works
The Baldwin Locomotive Works was an American builder of railroad locomotives. It was located in Philadelphia, Pennsylvania, originally, and later in nearby Eddystone, Pennsylvania. Although the company was very successful as a producer of steam locomotives, its transition to the production of...
.
Long hood forward is a fading practice. Most modern locomotives produced in the USA feature wide-nose Canadian comfort cabs
Canadian comfort cab
The Canadian comfort cab or wide cab is a broad-nosed cab design found on modern diesel locomotives. It occupies the entire width of the locomotive, and typically has an access door on the front of the nose...
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.
Great Britain
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 locomotiveTank locomotive
A tank locomotive or tank engine is a steam locomotive that carries its water in one or more on-board water tanks, instead of pulling it behind it in a tender. It will most likely also have some kind of bunker to hold the fuel. There are several different types of tank locomotive dependent upon...
. Apart from shunters
Switcher
A switcher or shunter is a small railroad locomotive intended not for moving trains over long distances but rather for assembling trains ready for a road locomotive to take over, disassembling a train that has been...
, the only single-cab class still in service in Britain is the British Rail Class 20
British Rail Class 20
The British Rail Class 20, otherwise known as an English Electric Type 1, is a class of diesel-electric locomotive. In total, 228 locomotives in the class were built by English Electric between 1957 and 1968, the large number being in part because of the failure of other early designs in the same...
. These are now usually operated cab forward
Cab forward
The term cab forward refers to various rail and road vehicle designs which place the driver's compartment substantially farther towards the front than is common practice.- Rail locomotives :...
(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.