I’m a newbee on a learning curve. Does anyone know of a source which explains what the letters that identify locos stand for, ie; GP, SD, RS,etc,etc,etc It would also be helpful if the site explained what the different ones where used for and a brief history. Web based would be good or perhaps a book I could buy.
I found The Encyclopedia of Trains and Locomotives General Editor: David Ross was very helpful in breaking the code. It covers the world, not just North America and covers everything from the dawn of railroads to present day. I feel it was well worth the investment. There are many photos and descriptions for upwards of 1,000 locomotives. I found it at my local Costco a little over a year ago. I just looked and it is currently available on Amazon for under $15.
If you want to do some online research, I’d suggest you visit Wikipedia and start by doing a search on the term “locomotive type”. There his a wealth of information available there. You should have pretty good luck in your quest using Google to search also.
These links might help some:
http://www.urbaneagle.com/data/RRdieselchrono.html
http://www.ole.net/~rcraig/MPR.html
http://en.wikipedia.org/wiki/Category:Diesel_locomotive_stubs
For quick reference, here are the meanings (as I understand them) for some letter model designations for several manufacturers:
EMD: GP = General Purpose, SD = Special Duty, SW = Switcher (it once stood for Six Welded - that is, 600 hp with a welded frame. Along this same vein they also made SC = Six Cast, and NW = Nine Welded), F = Freight, E = passenger (of course this doesn’t explain the use of F-40PH’s for passenger trains - sometimes the designations just don’t make any sense)
GE: U = Universal, B = two two-axle trucks, C = two three-axle trucks, DASH = doesn’t really mean anything, just used to designat the most recent line of “third-generation” diesels
ALCO: S = Switcher, RS = Road Switcher, RSD = used for six-axle road switchers, HH = High Hood (not used by Alco, just by railfans), FA = Freight cab unit, PA = Passenger cab unit, C = Century series, Alco’s “second generation” diesels
Baldwin: DS = Diesel Switcher (later shortened to S = Switcher), DRS = Diesel Road Switcher (later RS = Road Switcher), AS = All-purpose Switcher (?), RF = not sure what this means, but these were the “Sharknose” diesels
Fairbanks Morse: H - Hood diesels, C - Cab diesels
Each of these companies had their own ways of designating their diesels, and they all seemed to have some oddball models that got their own designations because they didn’t quite fit into the standard naming system.
Tom