Is there a prescribed method of classifying diesel locomotives? I mean, with steam they are: 0-4-0, 4-8-4, 2-8-0, etc.. Is there a similar method of classifying diesels, or is it just something one must learn? Thanks from a newbie, Copyright 2008 Jerry DeBene
I think it is called the "white" system from a Mr. White who developed it. Maybe I can google for it in the next few days. [edit] Found it. The Whyte system: http://www.thejoekorner.com/railinfo/steam.shtm Diesels are not exactly classified the same way, but understanding the Whyte system makes diesels easy. Copyright 2008 Jerry DeBene
Diesels are classified according to powered and unpowered axles in the trucks: B-B: two trucks each with 2 powered axles (GP40, etc) C-C: two trucks each with 3 powered axles (SD40, etc) A1A-A1A: two trucks each with centre axle unpowered (E8,etc.) There's more to it, but this is a start. Copyright 2008 Jerry DeBene
Electric locomotives in North America are also classified as Colin has described for diesels. One other note...if a loco has two 2-axle trucks at either end with all axles powered, it would be classified as a B-B+B-B. I believe that the UP had some experimental locos with strange power truck configurations. I can't recall any at the moment, but I'm sure other members more knowledgeable than I can fill in the blanks. Copyright 2008 Jerry DeBene
Would The UP DD40's and such be considered as "D-D" configuration? FL9's would be considered as B-C's Plymouth 25-tonner would be an A-A. Copyright 2008 Jerry DeBene
Actually, DD stood for Double Diesel; i.e. they had two prime movers in one unit. By the way, has anyone heard of the only A1A-D diesel? Copyright 2008 Jerry DeBene
Was that Baldwin's only attempt to produce a road diesel? Forgive me, I'm probably suffering from Oldtimer's disease. Copyright 2008 Jerry DeBene
No, Hank. It was an experimental version of the SDP45 made for the GN. Only one built, #322, later BN 6599. The engine was a testbed for a radial truck; the technology it pioneered was used in the SD70M, but this engine is little-known. It was scrapped after its function was served. Check the bottom of this page: http://www.northeast.railfan.net/diesel66.html I'm not sure what Baldwin you could be remembering; they made many road diesels. Copyright 2008 Jerry DeBene
FL9's are Bo - A1A's the 25 tonner would be a B or a Bo it goes something like this, A Bo is 2 axles separately driven. A B truck is 2 axles connected by rods or gearing. the same goes for C = 3 powered axles D = 4 powered axles most modern locomotives if not all. the axles are sparately driven (by the traction motor mounted oin the axle) and are therefore Bo-Bo's or Co-Co's. the difference between steem is the idler counts. Diesels count the axles and steam counts the wheels. so let's assume the GG1 electric is a steam engine - it would be a 4-6-6-4. but it isn't and the correct coding is 2-Co-Co-2. hope that helps Copyright 2008 Jerry DeBene
The o's are normally used only in Britain and Europe. In America, there were fewer diesels with non-independent axles, so the "o" is usually assumed. But then, a note about steam designation... in Britain, they count the axles. A Pacific would be a 2-3-1 to them. Copyright 2008 Jerry DeBene
Wasn't BN 6599 a A-1-A - B-B? I seem to recall an article in one of the early De Grosso BN Annuals about this unit. Copyright 2008 Jerry DeBene
No, Gary. Look at the site I mentioned. It is a single 4-axle truck. The axles in the truck can steer, like on SD70/80/90s. Copyright 2008 Jerry DeBene
No England is the same as us (Australia) and we count the wheels. Conntinental Europe counts the axles and it is the same as diesels as in the idler's are numerical and the drivers are alphbetical. Copyright 2008 Jerry DeBene
Oh, yeah... I do seem to recall having seen letters in steam wheel designations sometime. I was basing my statement on a book I remember, which I'm pretty sure was British, that labelled a model of a 19th century locomotive as a 0-2-1. Copyright 2008 Jerry DeBene
I believe the numbering in the UK and on the Continent is based on the number of wheels seen from one side, not the total number of wheels on an axle as is common in North America. So, a 0-2-1 in the UK would be an 0-4-2 in North America. Copyright 2008 Jerry DeBene
The UK uses the same system as the US, other European countries use the 'axle' designation, France is one I know for sure would call it an 0-2-1. Over here, we would have an 0-4-2 also. HTH Copyright 2008 Jerry DeBene
Australia is the same as the United Kingdom, so a Pacific is a 4-6-2. On the European continent, a 4-6-2 would be a 2-C-1. Copyright 2008 Jerry DeBene
In Europe, isn't the correct punctuation/capitalization 2c1, not 2-C-1? Or is nothing I remember right? Copyright 2008 Jerry DeBene
