Does the loco number have any significance in relation to the type of loco it is? and if not how "are" they #'d?
loco #'s
- Thread starter belg
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Now there is a simple question that requires a complex answer! I guess the short answer is yes and no, depends on the era and railroad. Others will no doubt add specifics. Most of the 50's era railroads numbered their loco "classes" within a number range. Then as they bought more locos of a given type than they had #'s for, they would either renumber or skip. If you have a particular road you'd like info on, someone can probably help you.
To add to what Gary said, some railroads (like the EL) used the numbers to indicate horsepower. For example, EL GP-35's generate 2500 horsepower, so their number series was 2500. It can be confusing when the railroad has more than one locomotive model with the same horsepower rating. The EL did. They also had U-25B's with 2500 horsepower. They to were in the 2500 number series.
Most RRs number locos about in series when they order a bunch of similar ones. They'll usually leave blanks for future purchases. Some of them get the number series so full up that they have to stick new locos in where they can. Eventually they have a wholesale renumbering.
I'll give a few British examples.
British railways uses 5 digit numbers. The first 2 were the loco class. Sometimes they used the 3rd number for variations and special equipment. The first number gave the power class, from 0 to 6.
The Midland Railway was reputed to have one rule: there should be no gaps in the system. If a number became available, the next loco built was given it, didn't matter if it was nothing like the ones on each side.
The Great Western used the second digit to indicate wheel arrangement.
Generally, within a series locos were numbered as built, delivered or ordered; if identical locos were ordered from different builders, each would be given a series of numbers.
I read that the Pennsylvania had a bag full of vacant numbers and they were drawn randomly as the locos were ordered.
It helps if there is some relationship between the numbers and the locos. If the staff has to memorize or look up which class goes with each number, you create fatigue and errors.
I'll give a few British examples.
British railways uses 5 digit numbers. The first 2 were the loco class. Sometimes they used the 3rd number for variations and special equipment. The first number gave the power class, from 0 to 6.
The Midland Railway was reputed to have one rule: there should be no gaps in the system. If a number became available, the next loco built was given it, didn't matter if it was nothing like the ones on each side.
The Great Western used the second digit to indicate wheel arrangement.
Generally, within a series locos were numbered as built, delivered or ordered; if identical locos were ordered from different builders, each would be given a series of numbers.
I read that the Pennsylvania had a bag full of vacant numbers and they were drawn randomly as the locos were ordered.
It helps if there is some relationship between the numbers and the locos. If the staff has to memorize or look up which class goes with each number, you create fatigue and errors.
