Long hood
The long hood of a hood unit-style diesel locomotive is, as the name implies, the longer of the two hoods on a locomotive, particularly American-type freight locomotives.
Equipment
The long hood normally contains the diesel engine, 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.Operating direction
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. This is a holdover from the steam era of railroads where almost all locomotives were built with the cab placed at the rear of the locomotive. 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. 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, wider radiators that blocked a larger portion of the field of view.United States
The railroads that held out the longest for long-hood leading were the Norfolk and Western Railway and the 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 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">Electro-Motive Diesel">General Motors Electro-Motive Division
- GP7
- GP9
- GP18
- GP38
- GP38-2
- EMD GP40
- GP40X
- GP49
- GP50
- SD7
- SD9
- SD35
- SD40
- SD40-2
- SD45
General Electric Transportation Systems">GE Transportation Systems">General Electric Transportation Systems
- B30-7
- U23B
- B23-7
- U30C
- U30B
- U33C
[American Locomotive Company]
- ALCO RS-11
- ALCO RSD-7
- ALCO RSD-12
- ALCO RSD-15
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.