Have fun with your trains
Dan
WOW, thanks Paul3, I did not realize that it was so complicated. But overall I think that I'm starting to understand it. I might have to do some additional reading on it. But this has giving me a start and I appreciate that. Honestly it seems as if they renamed the same loco over and over again to promote sales.
thanks Norman......
t_valley,The diesel nomenclature is a study unto itself. It involves engineers and salesman, and that's always an interesting mix at the best of times. Now add railfans and percolate for 70 years or so, and serve. Yum!
Anyways, each loco manufacturer had different ideas.
EMD (Electro-Motive Division of General Motors):They originally started calling them by their horsepower and (most of the time) frame type. An "E" unit had Eighteen hundred Hp, an SW-1 was a Six hundred Hp with a Welded frame, an FT was Fourteen hundred Hp (really 1350Hp) with a Truss frame, etc. This is something an engineer would come up with.
As time went on, the original idea became the lable for a series of locos. The E-units were up to 2000Hp and more but still called E-units, the F-units were soon up to 1500Hp, etc. This was the salesman part ("See our new, improved E-series!").
Eventually, EMD tried to build something to handle branch line service...something that didn't need turntables or wyes, yet had one cab. The BL-1 (demo) and BL-2 was the result...which stands for "Branch Line". This was not that successful.
EMD tried again with a new design that eliminated the truss car body and used a center sill frame design. They wanted it to be used for all kinds of service, so called it "General Purpose" or GP. Since it shared components with the F7's then in production, they called it the GP7.
EMD also wanted to produce locos with a lighter axle loading for lightweight branches of many RR's, so took a GP7 and added two more axles. These were called "Special Duty" or SD's. Later, RR's found that these SD's could pull more by spreading the amp loading over 6 motors instead of 4 as on a GP, so SD's then started getting longer and heavier and made great drag freight locos for years.
Meanwhile, RR's were looking for more Hp. EMD made a splash when they increased the GP9 from 1750 to 1800. To the salesman, this needed a whole new designation to pound home this improvement. So they used the Hp in the name and the GP18 was born. A GP18 has 1800Hp, a GP20 has 2000Hp, and a SD24 has 2400Hp.
In the mid 1960's, GE got into the loco business by themselves and introduced the U25B (with 2500Hp). EMD's engineers came up with a GP22 (with 2200Hp), and EMD's salesman said "Come up with some reason to call it a higher number than 25." So the EMD engineers said there were 30 improvements over the GP20, and thus was born the GP30 (higher in number but w/ fewer Hp than GE's U25B).
Confused yet? It gets worse. EMD then just named newer things with ever higher numbers. Again, a mix between engineers and salesman.
ALCO (American Locomotive Company):Alco had a simple nomenclature at first. They just numbered them all "DLxxx" for Diesel Locomotive" and a number starting with 100 (IIRC). A DL109 is the ninth diesel design, and a DL701 (RS-11) is the 601st. Meanwhile, railfans were getting headaches from trying to keep it all straight. They dubbed passenger A units as "PA's", freight A units as "FA's", road switchers as "RS's", etc.
Finally Alco woke up to marketing, and came up with the Century series of locos with their 251 engines. This was done primarily to distance themselves from their problematic 244 prime movers that game many RR's cause to ignore Alco. Century nomenclature was "C" for Century, then the number of axles, then the Hp in hundreds. So a C-425 was a Century loco with 4 axles and 2500Hp. This made sense, and is what Alco used right to the end for US RR's.
GE (General Electric):This deserves it's own chapter. Originally, they had their "Universal" line of locos. Therefore a U25B was a "Universal" loco with 2500Hp and a B-B wheel arrangment (a U25C had six axles). This lasted a while.
Then they came up with the "-7" line. These all shared common electrical components that added solid state components to locos for the first time (IIRC). Since this was developed in the 1970's, that's probably why they called them "-7". At this time, they dropped the "U" and reversed the wheel arrangement and Hp. So what was a U23B became a B23-7 with new electronics.
GE in the 1980's added microprocessors to locos and called them "-8" (probably for the 1980's). So a B30-7 would be a B30-8 with new electronics.
These locos started to become known as "-8's", so GE went with the flow and publically call these "Dash 8-40B" instead of "B40-8".
More improvements followed, so the "Dash 9" series of locos were introduced.
Then it was improved again with the optional use of AC traction motors. To make the difference apparent to all, they renamed their locos "AC" followed by the Hp. So a AC4400 is a 4400Hp loco with AC traction motors (vs. a C44-9W or "Dash 9-44W" for a DC motored loco).
Now they have "GEVO's" (Evolution series) which are more effecient and comply with new FRA emission laws.Baldwin, Lima-Hamiltion, also had their own nomenclature, but that's enough for me today. I gotta finish my lunch...
Corrections welcome. All of the above is from memory, so I could be wrong here or there...
Paul A. Cutler III************Weather Or No Go New Haven************
dinwitty,Technically speaking, the "-" indicates that something is connected through a common frame, not a common truck. Therefore, "B" does not equal "A-A". An "A-A" would be something like MDC's Model 70 center cab switcher (a "bobber" or two axle loco, IOW).
Something like an E-unit, a DL109, or a PA-1 would therefore have an "A1A-A1A" wheel arrangement (not "A-1-A, A-1-A" as there is no comma in this scheme, either).
To some, a "+" indicates an articulated frame. So a GG-1 has a 2-C+C-2 wheel arrangement, and a Big Boy is a 4-8+8-4. However, this is still debated with steam (the electrics seem to have settled on the plus sign as OK, but not all the steam fans agree).
t_valley wrote:Okay I think that I now understand the A,B,C and D/0-6-0. Thank you all for explaining it to me. But now here is another question pertaining to this: Where do they get the name GP-40 or SD40-2, what makes it one or the other or something different.
A little more complex, the dismal guys may clarify it better than this old steam dude but GP stands for General Purpose, SD is Special or Specific Purpose. GP engines were designed to used for pretty much every use, road switching, hauling local trains, whatever use was needed, hence "general" purpose, SDs were specific in their use, or at least that was the intent, long distance hauling, specific load catagories, etc. But the Irony of course is that the RRs use whatever they have however they feel its best used, so thats why you will still see GP40s on long distance frieght hauling and the occasional SD70 shoving cars on an industrial spur.
The numbers are model designations, GP-9 being General Purpose Model #9, which was followed with improvements, enlargements that gave way to different model #s being applied, GP-12, GP-20, GP-40 etc. each being a specific model. SD-40-2 or dash 2 is a specific improvement to an individual model that doesnt change the base platform but differentiates the model non-the-less.
I'll let the dismal guys explain that part better than me.
well to confuse further...you could be calling a B-B an A-A, A-A, it still means all wheels powered but thats just to clarify the powered axles. But thats not how we do it. B indicates one truck 2 axles powered, 4 wheels. C = 3 axles powered and 6 wheels. A-1-A will mean 3 axles, but the 2 outer axles powered, middle not, but 6 wheels, on one truck. Then you have the D = 4 axles 8 wheels powered.
In France, they counted the number of axles, not wheels (or more simply, the number of wheels that were visible on one side of the locomotive). For instance, a Pacific style of locomotive 4-6-2 here in America was called a Pacific 2-3-1 in France.
There's actually a 15-minute long 20th Century work for symphony orchestra written by the French composer Artur Honnegger called "Pacific 231", which orchestrally depicts a French steam locomotive starting, running at top speed and then coming to a gradual halt. It sounds pretty darned realistic, in fact.
Tom
Tom View my layout photos! http://s299.photobucket.com/albums/mm310/TWhite-014/Rio%20Grande%20Yuba%20River%20Sub One can NEVER have too many Articulateds!
t_valley wrote: wjstix wrote:Just to confuse things, diesels (and electrics) use a combination letter + number system: A=1 powered axle, B= a truck with two powered axels, C= a truck with three powered axles, D= a truck with 4 powered axles. Numbers are used to show non-powered axles.So for example a GP-9 is a B-B engine - 2 two-axle trucks with both axles powered. An SD-9 is C-C, 2 three-axle trucks all powered.An E unit, say a E-9 passenger engine, at first looks to be C-C also, but it really is A-1-A / A-1-A, meaning the it has 2 three-axle trucks, but only the outside axles are powered, the middle one is an idler (the "1") and unpowered.Confused yet?? The only part that confused me was.......A=1 powered...................confused yet. Maybe if you wouldn't mind explaining that system with an engine I can look at would help like say a GP-40. thanks Norman....
wjstix wrote:Just to confuse things, diesels (and electrics) use a combination letter + number system: A=1 powered axle, B= a truck with two powered axels, C= a truck with three powered axles, D= a truck with 4 powered axles. Numbers are used to show non-powered axles.So for example a GP-9 is a B-B engine - 2 two-axle trucks with both axles powered. An SD-9 is C-C, 2 three-axle trucks all powered.An E unit, say a E-9 passenger engine, at first looks to be C-C also, but it really is A-1-A / A-1-A, meaning the it has 2 three-axle trucks, but only the outside axles are powered, the middle one is an idler (the "1") and unpowered.Confused yet??
Just to confuse things, diesels (and electrics) use a combination letter + number system:
A=1 powered axle, B= a truck with two powered axels, C= a truck with three powered axles, D= a truck with 4 powered axles. Numbers are used to show non-powered axles.
So for example a GP-9 is a B-B engine - 2 two-axle trucks with both axles powered. An SD-9 is C-C, 2 three-axle trucks all powered.
An E unit, say a E-9 passenger engine, at first looks to be C-C also, but it really is A-1-A / A-1-A, meaning the it has 2 three-axle trucks, but only the outside axles are powered, the middle one is an idler (the "1") and unpowered.
Confused yet??
The only part that confused me was.......A=1 powered...................confused yet. Maybe if you wouldn't mind explaining that system with an engine I can look at would help like say a GP-40.
thanks Norman....
A GP-40 would be a B-B engine. There are two trucks with two axles each, both are powered. An SD40-2 is a C-C engine, 2 trucks, 3 axles per each truck, all axles are powered. Or the Monsterous DDA40X, which is classified as a "D-D", 2 trucks on the loco, 4 axles per truck, all axles powered. Now lets say we had an engine designated A-2-A/A-2-A. Even there is no real engine with this arrangement, it would be 2 trucks to an engine, 4 axles to a truck, only the outer two axles of the truck are powered, thus the middle two are 'idlers'.
Get it?
Paul3 wrote: t_valley,About the ABC's (literally) of diesel wheel arrangements...The Whyte classification system was created in the days of steam and assumed that all powered wheels are in the center of the loco. Also, it assumed that pilot and trailing wheels on either side of the center wheels were not powered. This leads to "0-6-0", "4-8-2", etc. If they were articulated steam engines with multiple sets of drivers, they would get added in the middle as well. Such as "4-8-8-4" for a Big Boy, or "2-6-6-6" for an Allegheny. Diesels, of course, are very different in that most diesels have all powered axles and no pilot or trailing axles as on a steam engine. If one were to use the Whyte system for a GP40, it would be "0-4-4-0". This is cumbersome, and not very descriptive. Therefore, a separate system has been developed that uses letters for powered axles and numbers for idler (or unpowered) axles. A GP40 thus becomes "B-B".Paul A. Cutler III************Weather Or No Go New Haven************
t_valley,About the ABC's (literally) of diesel wheel arrangements...
The Whyte classification system was created in the days of steam and assumed that all powered wheels are in the center of the loco. Also, it assumed that pilot and trailing wheels on either side of the center wheels were not powered. This leads to "0-6-0", "4-8-2", etc. If they were articulated steam engines with multiple sets of drivers, they would get added in the middle as well. Such as "4-8-8-4" for a Big Boy, or "2-6-6-6" for an Allegheny.
Diesels, of course, are very different in that most diesels have all powered axles and no pilot or trailing axles as on a steam engine. If one were to use the Whyte system for a GP40, it would be "0-4-4-0". This is cumbersome, and not very descriptive. Therefore, a separate system has been developed that uses letters for powered axles and numbers for idler (or unpowered) axles. A GP40 thus becomes "B-B".
Paul, me being steam guy, what about dismals that had idler wheels, like the Alco PA-1, where the center axle in the 6 wheel truck was there just for weight distribution? Now would that be refered to as a A-2-A ? or how is that?
NeO6874,That's pretty much the case. A Pacific in certain Euro countries would be 2-C-1 (Whyte: 4-6-2).
The one thing that did not translate to American practice was the small "o" for nose hung traction motors. For example, in the Euro method, that GP40 would be a Bo-Bo. If it doesn't have the "o", it meant that it was connected to siderods as on a steam loco (something fairly rare on US RR's). I don't know what they would have called a E-unit (Ao1Ao-Ao1Ao?).
As Mr Garrison on South Park would say "There are no stupid questions, only ..."
Oh ...well nevermind
As stated above, 3 pairs of driving wheels with no lead or trailing wheels = 0-6-0, if the locomotive had no tender but carried its water and fuel on tanks attached to the engine its reffered with a T as in 0-6-0T.
Example, my ohhh-six-ohhh
Sorry it doesnt include the tender, this was a progress pic during construction
selector wrote: Someone bigger'n me who objected to my use of the 0-1-0 gave me a black eye for my trouble.
Someone bigger'n me who objected to my use of the 0-1-0 gave me a black eye for my trouble.
Wouldn that be a 0-1-0-0 ?
I believe the diesel style of classifying locomotives is an adaptation of European classification in which they count AXLES rather than total number of WHEELS. (Though I could be mistaken on this)
-Dan
Builder of Bowser steam! Railimages Site
Well, there are no dumb questions, but it appears there are plenty of dumb answers!
Lee
Route of the Alpha Jets www.wmrywesternlines.net
Railphotog wrote:If you ever come across the term "0-5-0", don't get confused, there aren't 2-1/2 wheels per side - it refers to ones' hand - the "0-5-0 switcher", picking up cars with your hand!
If you ever come across the term "0-5-0", don't get confused, there aren't 2-1/2 wheels per side - it refers to ones' hand - the "0-5-0 switcher", picking up cars with your hand!
Ot he HOG method. (Hand of God)
dale8chevyss wrote: Railphotog wrote: If you ever come across the term "0-5-0", don't get confused, there aren't 2-1/2 wheels per side - it refers to ones' hand - the "0-5-0 switcher", picking up cars with your hand! also referred to as the "five finger discount."
Railphotog wrote: If you ever come across the term "0-5-0", don't get confused, there aren't 2-1/2 wheels per side - it refers to ones' hand - the "0-5-0 switcher", picking up cars with your hand!
also referred to as the "five finger discount."
...well, only if the cars you're picking up don't belong to you !!
From the far, far reaches of the wild, wild west I am: rtpoteet
Modeling the N&W freelanced at the height of their steam era in HO.
Daniel G.
Bob Boudreau
CANADA
Visit my model railroad photography website: http://sites.google.com/site/railphotog/
t_valley wrote: I know that this is a silly question, but I'm one of those silly few that don't know. I know that it is used to describe a locomotive but how? What exactly does this mean? thanks Norman....
I know that this is a silly question, but I'm one of those silly few that don't know. I know that it is used to describe a locomotive but how? What exactly does this mean?
The only dumb question is the one not asked. No one knows everything about everything. Every person in here had that explained to him (or her) at some point in their life.
Every person in here is here to A) Share what they know, and B) Learn what they don't know. Through that sharing, we all become better at this hobby.
Dave
Lackawanna Route of the Phoebe Snow
It's the Whyte system of classification. This list gives the wheel arrangements and names of the ones with names http://www.steamlocomotive.com/misc/wheels.shtml
Enjoy
Paul
Thanks railphotog, for the quick response. I thought that it had something to do with the wheels but was unsure.
Thanks again Norman....