It wasn't uncommon for early cab units to be provided as A-B-A or A-B-B-A sets, giving the effect of a double-cab articulated locomotive with modular 'units'.

It was always my impression that some railroads wanted a more 'streamlined' appearance by using only B units in the trailing consist. At the other end of the 'spectrum', commuter operations (where you'd expect double-cab power, and in fact find it on CNJ with the early Baldwin 2000hp units) generally went with road-switchers as soon as possible, or with 'push-pull' car consists wired up to be driven from an operator's cab at the distant end in the "reverse" direction, so the locomotive didn't have to be run around the train. (This also facilitated HEP operation, but that's another story.)

Up until the late 1940s,unions were attempting to require a fireman in each unit of a MU consist -- it was bad enough that one was required on a diesel locomotive in the first place -- and a number of American railroads got around this risk by buying consists as "locomotives". In one case, on Chicago Great Western, there was a 7-unit consist of F units all with the same road number, the 'units' being sublettered up to 'g'. PRR had a number of early locomotives that were numbered identically by 'set' and as I recall the actual locomotive builder's plates had to be modified to reflect the 'separation'.

Regarding the HEP/Waukesha Ice Engine discussion: if you can find a copy of Paul Kiefer's 1947 survey of motive power, there is a graph that shows the acceleration of a train, and you can clearly see the individual points where the Spicer-driven generators on the cars cut in.

The early road diesels weren't as 'rock solid' reliable as the manufacturers were making them out to be. On the B&O, with the original EA's EMC required a 'Diesel Rider' position to keep a close eye on the Winton 201 prime movers which were not reliable. Diesel Riders were out of the mechanical department and could make a number of repairs 'on the fly' - anything to keep the locomotive moving to the run's destination and alert the Mechanical Dept. at destination what repairs will be necessary to keep the engine in its normal roatation.

Keep in mind that "repairs on the fly" could include the ability to change out power assemblies, with a chain hoist conveniently provided on a rail to facilitate the operation. (Naturally these were cab units or motor trains!) There have been several accounts in magazines by riding maintainers about some of the details.

Short answer, because control equipment costs money, and cabs waste space. Since the standard procedure was to send the loco to the servicing area at the end of the run, it could be turned there, same as steam. Anyway, it was quickly realized that given the power of early diesel locos relative to the size of the trains, each train was going to require multiples of locomotive "units" assembled into an adequate sized locomotive consist for the intended load. As Overmod pointed out, if two of these units had cabs arranged at opposite ends of the consist, the entire consist becomes double ended.

Some service could benefit from locos with two cabs, such as local service where the train goes back and forth between terminals several times without any servicing, and indeed the Jersey Central did have Baldwin build diesels with two cabs, but other roads were discovering that the new 'road switcher' configuration, with the cab midway along the carbody, was essentially bi-directional if equipped with a control stand on each side, so that became the dominant form of power in service where the power frequently changed direction.

Meanwhile, most of the roads that had commuter operations in Chicago had dieselized with E and F type end cab units, and the Chicago and North Western pioneered 'push-pull' operation, where the locomotive stayed on one end of the train, and a control cab was installed in the last car for use in the other direction. This then spread to the other Chicago roads, and elsewhere.

So, there was never a real need for double cab locomotives.

I should add the CNJ's Baldwin 2000 HP double-ended cab units were not successful and were replaced by new FM TrainMasters in 1956. The double-ended construction was not the problem, though.

As to the Winton 201A engine, it might have been the best engine for the job in 1934, but by 1938 both EMC and Winton (Cleveland) had developed new designs for their specific uses. EMD: 567; Winton: 248, 248A. The EMD is numberred for the cubic inches in each cylinder while the Winton is in the Winton sequence. The Winton is actually a bit bigger. All are two-stroke cycle, roots blower uniflow engines.

Phil Mulligan

But why they where not a succes?
Forgot about the end command in the some trains. Push-pull system.
And how come in the eraly days that companies accepted repairs on route? They considered Diesel to be more advantageous?

Yes, even with the early mechanical teething problems, Diesels had a clear advantage over steam. Less overall maintenance needs, higher availability, and smaller crew requirements being the major ones. Just about every major U. S. railroad would have Dieselized 10 years sooner than they did had it not been for the production restrictions of WWII. And believe me, even die-hard steam fans like myself have to admit that.

I vaguely recall a Trains magazine article years ago authored by a gentleman (whose name slips my mind) who started his career in the Pennsylvania Railroad mechanical department. In it he recounts a roundhouse foreman complaining that the new EMD passenger locomotives had only been on the property several months and already needed their wheels re-profiled... "Must have used cheap steel" he said. Our author tabulated the service records and realized that the E units had already racked up mileage that was multiples of what the Pennsy was getting out of steam, and used his next opportunity to jump ship and go to work for EMD. I recall his comment was that any locomotive that was capable of that kind of utilization was surely the wave of the future, and he was right.

But I wonder, if the income pressure wouldn't have had camed on U.S.A. passanger rails in the '50's, there would have been more steam locomotives preserved in U.S.A.?

The 201A was a good engine; GM's competitors came out with better engines so GM had to improve its product. So GM produced two designs, each optimized for its use.

FM produced an excellent diesel in the 38 8-1/8 opposed-piston and US submariners preferred it to the GM Cleveland 278A (descended from the 201A and 248). In railroad use it did not work out as well. Some USN Nuke boats still have 38 8-1/8's as emergency power.

PRR noticed one 3-unit EP20 (EMD E7) could run through from Harrisburg to Chicago while steam changed at Pittsburgh and Crestline.

Brother Storzek refers to a PRR foreman at Harrisburg Enginehouse who, in mid-grumble, realized his two EMD E7's had not been in the enginehouse in their first 6 months and had not missed a run to Detroit and back in that time. Meanwhile his enginehouse was full of new, bad order, T1's awaiting repairs. There was an EMD guy on the property and they did work on the E7's in the yard. 5901 of that E7 pair is at the RR Museum of PA.

Phil Mulligan

But how "Norfolk & Western" used steam locomotives more then other companies?
It's a pitty that intresting and beatiful steam locomotives wheren't preserved in more pieces or wheren't preserved at all. A steam locomotive is intresting even for persons who are not intrested in trains.
One intresting pice of tech that was used at trains was the steam ejector, used for cooling. It was used in buldings too, I've read, but I wonder if any building uses it today. In Romania we have some cities that are using centralised heating, meaning that hot water is pumped from power plants and that passed to heat exchangers to provied hot water and heating. Well, in Bucharest the system haves problems because after 2010 it was bad mainted. But with reheated water, in the summer, you can have steam ejectors. Anyway, does any one can please recommed me a book or a site about old (and maybe new) steam ejectors.
Here are some "New York Central" cars. 2. I guess the light wheight where a big step ahead. Less rail wear and with the same motive power, you could move more cars. Maybe they where more expensive, but during time, it did cut costs.



From "Teatrul Naţional/The National Theatre" magazine 1936/1937.
The add is saying aprox.: The rythm of the modern life asks more and more the presence of the telephone! In the friendly relations, but also in your (economically) activities the telephone is indispensable/essential! Subriscibe to the telephone [service]!
You can see one of the progress signs was the "Union Pacific" streamlined M1001 (or M100x) train... pitty that such sign of progess wasn't preserved. It was very fast.



At last, an very intresing locomotive!



Oh, I forgot. Above I asked about steam ejectors. In think U.S.A. was the only country or one of the fewest that did used Arhimede's screw for feeding the boilers of some big locomotives. In Romania we did used that in central heatings in the past... one Romanian company used the "Autocalor" named for it.

I'll start with N&W. Their later steam power was very modern and designed for easy servicing. N&W served the coal field that produced its fuel so shipping costs were as low as possible. They were also committed to steam.

Steam ejector air conditioning (A/C) was a rarity and more expensive than other types. The advantage with rail equipment is that locomotives were able to provide plentiful steam. Postwar electro-mechanical A/C proved superior and only Santa Fe stayed with steam although the High-Level cars used diesels to genrate power including powering electro-mechanical A/C.

The light weight of the NYC&HR wood passenger cars reflected their weak structure that easily collapsed and burned in a wreck. The roads did need larger locomotives to move the new, steel cars but the safety aspect made the expense necessary.

The US RR's did not use an Archimedes screw to push feedwater into the boiler. Initially, they used pumps mechanically dricen from the side rods; from about 1860, they used injectors and in the 20th Century steam pumps associated with feedwater heaters.

That said, the auger in a mechanical stoker is basically an Archimedes screw used to move coal from the tender to the locomotive and lift it up to a point where it can be spread over the grate by steam jets.

Going to an older thread, almost all USA Electric locomotives are and have been double-ended.

Phil Mulligan

I've quoite thinked that "N. & W." had easy service locomotives, based on what I've seen, but in what that easy servicing consisted?

To add to what Phil said, the 'Archimedean screw' is clearly the stoker worm, used to comvey solid fuel from a bunker to where it can be distributed into the firebox. Early stokers didn't quite figure out how to do this for specialized locomotive stoking; the Street underfeed stoker was promising in practice derived from stationary application, but was NOT the best approach for large locomotives for a variety of reasons.

The actual thing that replaced stroke pumps in locomotive boiler feed was the Giffard injector, and the development of this design for railroad service, and then extension into low-pressure use with exhaust steam, is its own rich and interesting topic.

Feedwater heater pumping requires more careful detail discussion. The normal locomotive FWH system required two pumps, usually of very different characteristics. The cold-water pump lifted water from the tender up to the heating apparatus; this was commonly a centrifugal pump driven by a small steam turbine, as it did not need to be positive-displacement and would not require a bypass and relief valves. On the other hand, the hot-water pump was needed both to prevent the heated water from 'flashing' and to compress it to enter the considerably hotter and higher-pressure boiler space. These were positive-displacement pumps, usually piston pumps in practice. Toward the end of steam, Hancock developed a system that used one turbine to accomplish multiple pumping tasks at lower weight and (nominally) lower cost, which they called the 'Turbo-Inspirator'. This is notably the device used on the PRR T1, NH I-5, and (as built) Ross Rowland's J3a Greenbrier. It acquired a bad reputation in service, in part for the same general sort of reason Caterpillar engines haven't caught on in the diesel repower market or Krauss-Maffei high-speed-engined power failed to thrive: if you didn't maintain the things diligently, more or less exactly to factory spec, catastrophic things might follow in short order.

Of the electric locomotives that reached and still reach N.Y.C. , there where any that could get directly into the tunnel systems, without the special reqyurment of the tunnel locomotives.
Any Diesel-Electric that could do that?

Other thing: I thought that the windows of Grand Central Terminal where simply windows. Found out that some of them where Luxfer prisms, so prismatic lights.
One underground old garrage in Bucharest have a turntable (that dosen't works as far as I know) with a "mushroom" with such prims. Apartament bulding garrage, pre-1948.