Why Are American Locos So Different?

Most drivers seem to sit almost on the side and there seems to be lots of levers and all sorts, where as our locos in the UK seem to be more simple.

Why is it that American Locos (not all of them I know!) are that same F(?) style series?

US railroads tend to buy their locos from manufacturers (Alco, Baldwin, EMD, Budd, etc.) whereas UK railways generally preferred to design and build their own. So many railroads had the same designs, as that's what was available.

whhistle said:

Most drivers seem to sit almost on the side but there seems to be lots of levers and all sorts, where as our locos in the UK seem to be more simple

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I always thought exactly the opposite, most of the US locomotives are of a single cab hood type so I would have thought that the drivers controls are duplicated for either direction of travel in a similar manner to our class 20s etc. If you take a typical twin cab loco such as a class 47, as well as the cab mounted instruments indicator lamps and switches etc. there are also several other control panels situated throughout the engine room with more dials & gauges than you could shake a stick at, which simply could never all be accommodated within the driving cab.

I think the short answer is that down to the Americans have a very different railway.

Their locos can be, and are, much larger (height and width) and heavier, and to work much heavier trains, multiple working has always been the norm. The other thing is that, since the diesels came in the 1930s, locomotive development has substantially been driven by the loco builders - now EMD (Electro-Motive Division of General Motors) and GE (General Electric (the American one)) - it's largely been a case of choose options (most notably livery - in the 1950s EMD had a design studio to come up with paint schemes!) on a range of standard models. Since the 1950s - on a largely non-passenger railway - aesthetic design has also taken a back seat (when EMD first introduced hood units, they were worried the railroads would give the thumbs down to such ugly locos!, a fear which didn't last) And there is a lot of standardisation of things like control stands and mu equipment to provide for interoperability between different makers' models of different roads. I think the only exports of American 'domestic' models have been to the (American style) iron ore railways in Western Australia - the only railways that can accommodate them: the builders have had a separate range of (smaller) export models for elsewhere (often built locally under license).

While single cabs locos have always have been almost universal (there have been more built with none than two), they are normally just have one set of controls (I think two has always been an option, along with which way they face- there is generally an 'F' painted on the frame to indicate which end is regarded as the front).

Function creates the form, yes, ok, but I also always wondered why american locos still had so primitive, ugly, unpractical, and anti-ergonomic controls.

MarcVD said:

Function creates the form, yes, ok, but I also always wondered why american locos still had so primitive, ugly, unpractical, and anti-ergonomic controls.

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I guess you are talking about the traditional 'control stand' arrangement?

When the loco manufacturers moved from the traditional narrow-nose cab design (e.g. as fitted to EMD GP40/SD40 locos) to the modern 'wide-cab' design with a full-width nose, they also changed to a 'driving desk' control layout - basically similar to a typical European layout.

Only problem was the crews didn't like them...they much preferred the control stand, as it was more practical and had more flexibility in the driving seat positioning.

So the loco manufacturers moved back to a modernised version of the control stand and the crews are happy again...

From what I've read, the main reason drivers prefer the control stand is because you can operate all the main controls with one hand (power, reverser, brakes) - which is very useful if you need to lean out of the cab side window when switching (shunting) freight cars around, or when starting a heavy train and you need to look down at the ground to check when you start moving.

Doesn't modern locs have sort of 'mini controls' on the sides of their driving cabs to allow making shunting moves while leaning out of the lateral windows ?

MarcVD said:

Doesn't modern locs have sort of 'mini controls' on the sides of their driving cabs to allow making shunting moves while leaning out of the lateral windows ?

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I don't *think* so on US freight locos i.e. I've never seen/read anything about it.

There are some 'inside the cab' views here for an SD70ACU rebuild here - http://www.nsdash9.com/NSJuniata2016/nsjls2.html (EMD controls in a 'wide' cab) - an AC44C6M rebuild here - http://www.nsdash9.com/NSJuniata2016/nsjls12.html (GE controls in a 'wide' cab) - and a GP59ECO rebuild - http://www.nsdash9.com/NSJuniata2016/nsjls9.html (EMD controls in a 'standard' cab).

Note the standardised layout of the power and brake handles in all three cabs - dynamic brake, throttle and reverser (top to bottom at front), train air brake and loco independent brake (top and bottom at rear).

For comparison, this is the rather less complex control stand of a 1970 EMD DDA40X 'Centennial' loco (at the Western Pacific Railroad Museum): https://flic.kr/p/C71h5R

Hmm i do not know what the problem is. As long it is doing its job.

A curious thing is that most American electric locos are/have been double ended- though dual mode ones are (mainly) single cab.

The starting point in US loco design is level crossings. They have so many collisions on the unguarded (and guarded) ones that for major operators they invariably have a few units in the repair shop with smash damage. So most US locos have had noses, to safeguard the crew. These have somewhat shrunk over time, but are still there, typically well reinforced inside with heavy girders. The original ubiquitous "Geeps" were normally built with the cab, at the three-quarter point, actually at the rear, with the main body ("long hood") ahead, like a steam locomotive, and narrow enough to look past. Later this was turned round so the ran "short hood" forward, and later still the centre part was reduced in height so the crew could look over it. Two of the traditional mainstream railways, Southern and Norfolk & Western, never went for this, and until much more recent times ran all their locos long hood forward.

Their electric locos differ to an extent because electric lines typically have far less level crossings than the rest of the system, and US electrics are generally passenger only, not hauling huge freights with many locomotives.

Taunton said:

Their electric locos differ to an extent because electric lines typically have far less level crossings than the rest of the system, and US electrics are generally passenger only, not hauling huge freights with many locomotives.

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Or at least it is so today. But not in the past. The Milwaukee road ran into very rural area, and had noseless locos nevertheless. And many electric operations were established to cross mountain sections too. But may be 80 years ago the level crossing issue was much less problematic.

MarcVD said:

But may be 80 years ago the level crossing issue was much less problematic.

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I think it probably was much less of an issue in the 1930s/1940s.

The 'single cab' situation with diesels evolved over time.

In the 1930s EMC/EMD and others produced end-cab low-hood diesel switchers (shunters) and effectively 'power cars' for the 1930s streamlined, lightweight, passenger trains. To make them look modern/futuristic they were styled with curved, swept back noses. This design styling evolved into the twin-engined E-unit passenger locos by 1937.

But the big market was obviously for freight power, so when EMD had developed a diesel engine powerful and reliable enough for that market (the V16 567 series) in 1939 they produced a 5400hp demonstrator set - the model 'FT' - made up from four 1350 hp 'power units' with a cab at each end of the set. They kept the styling and basic construction techniques of the E-unit, and the four units were semi-permanently coupled together to effectively create a single, cab-at-each-end, locomotive roughly equivalent in power to the largest steam locos of the time. The middle units of the set were cab-less 'booster' units.

That went down a storm with the railroads, and made the curved, swept-back 'cab unit/carbody' styling commonplace for the next 20 years or so. For flexibility, the semi-permanent couplings were soon replaced with standard AAR couplers, and railroads just mixed and matched cabbed and cab-less units, turning the cabbed units on turntables and 'wye's as necessary.

Problem was, while the F-units were fine for hauling mainline 'road' trains, they weren't very good for switching/local freight use due to not-so-good visibility from the cab. ALCo sorted that problem with the first 'road switcher' design in 1941, the RS-1

(image from Wikipedia - https://commons.wikimedia.org/wiki/File:DSSA_RS-1_(cropped).jpg )

EMD copied the idea in 1949 with the GP7 series, and the 'road switcher' design slowly evolved into today's near 200 tonne, wide-cab monsters.

An EMD F-unit cab and booster pair (with the nose of an EMD switcher on the right):

EMD FP7 WP 805-A and train by ac6044cw, on Flickr

An early EMD SW-1 switcher:
EMD SW1 WP501 by ac6044cw, on Flickr

An EMD GP7 (right) and GP9 (left):
WP GP7 and SP GP9 by ac6044cw, on Flickr

A 1969-vintage EMD GP38-2 (note how small it is compared to the modern loco behind it):
GMTX 2681 by ac6044cw, on Flickr

A snow-fighting equipped GP38-2:
Snow equiped GP38-2 by ac6044cw, on Flickr

A typical modern GE 'road switcher' - an ES44:
CN #2935 at Whistler by ac6044cw, on Flickr
Climbing west out of Revelstoke - 2 by ac6044cw, on Flickr

The American class 900 for Amtrak was a copy of a Swedish locomotive.


Source: Hebners.net

I suspect one reason most of the US electric locos are double-cab is that they have always been quite powerful, so most trains only needed one or two to match equivalent steam power, but early diesels were relatively low-powered and hence needed multiple locos to get the same power. If you doing that then you might as well save the cost of the cabs and just arrange to have a cab at each end of a multi-loco consist.

It's very common to have on local freight workings (which have to do a lot of freight car switching en-route) a pair of GPxx 4-axle locos coupled tail to tail, making up the equivalent of a 4000-6000 hp double-cab loco, or a 'mother and slug' combination which looks much the same but the 'slug' has no diesel engine (its traction motors take power from the 'mother' loco at low speeds, providing more tractive effort).

Mother and Slug set (slug is leading - note the radiator grilles at the rear are plated over) - the location is Point of Rocks, MD:


(Photo by Mark Levisay from Ruckersville, VA, USA - CSC_6655-1, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=31728574 )