North African railroads

[Bronsky]

Jon, thanks for the picture.

I think the picture leaves little doubt that the Whitcombs on the desert railroad were of the same type as the types described in the link.

The link shows different types of Whitcomb 65 DE locomotives. I assume that they must be fairly similar, but don't know the difference between the types. They do all look alike. On another link about the 65 DE 19, the locomotives are described as sometimes having reliability problems, the piston heads being a specific problem. On the other hand, they were good pullers and they could run for a very long time. Also, the type was specifically designed so that the locomotives would be modular i.e. that 2 or more could be coupled for more traction if necessary.

Finally, top speed of the 65 DE 19 is given at 45mph, fast for a military locomotive of the time. Assuming that this is the same type that the French received as Marshall aid, then the French number of 65 km/h (~41mph) being lower isn't really surprising for a second-hand machine.

It may simply have been faster to use the two-step method you outline by first laying a long line of semi-interimistic track and then following up with the ballast (transported by train, I presume?), rather than have the rail builders wait for the ballast guys.

I don't know much about engineering, but I know a fair bit more about that kind of tradeoff and suspect that the main benefit is not to save time on overall construction. The idea is that as long as you don't care about comforts too much, then the two-step approach gives you an at least partially operational rail line more quickly. The overall process takes longer, obviously, but if you need supplies to the front NOW then you will pick having a not quite up to speed rail line today and a fully-equipped one the day after tomorrow, rather than having the fully-equipped line tomorrow. Compare it to credit purchasing, if you wish: it's more expensive in the long run, but you don't have to wait for the goods.

[JonS]

The interval between the two companies isn't explicitly stated, but implied to be quite short. Also, the ballast was whatever was available to hand, rather than specially quarried and graded rock.

ESR rolling stock was un-braked, engine or otherwise.

[Michael Emrys]

It's interesting to me that the type shown is what I (admittedly no connoisseur of RR engines) would have recognized as a switch engine due to the layout of the cab at the middle. I can see a point to using that layout in the WD, because it could be driven back and forth on a single track line without needing a roundhouse or turnaround. But I wonder if the type was selected on that account, or was it just serendipity?

Michael

[Jon G.]

I googled a bit around for the Stanier 8F and found this rather technical bit of text about the 8F - according to which it did have brakes (anything else would have been surprising ), but also that crews complained about the poor brakes on the 8F.

Here is another set of specs for the Stanier - obviously overall similar to the picture JonS kindly provided me with, but from this set of specs it's evident that the 8F used superheaters, a contraption meant to 'overheat' the steam produced in the boiler in order to generate higher psi steam pressure. Superheaters are notoriously fragile and prone to clogging particularly if poor quality water is used - so I should stress that the performance calculations on p 4 of this thread apply only under ideal circumstances.

[Bronsky]

ESR rolling stock was un-braked, engine or otherwise.

The cars were un-braked and there are various anecdotes in the Italian history where Italian engineers gloat at their German counterparts not taking that bit into account.

The locomotives must have been, otherwise I don't see how the rail line could have been operated at all. That being said, gradient was practically nigligible between Alexandria and El Adem so with that very flat landscape the lack of brakes wouldn't be as much of a problem as in other regions.

It's interesting to me that the type shown is what I (admittedly no connoisseur of RR engines) would have recognized as a switch engine due to the layout of the cab at the middle. I can see a point to using that layout in the WD, because it could be driven back and forth on a single track line without needing a roundhouse or turnaround. But I wonder if the type was selected on that account, or was it just serendipity?

As I wrote, the reason for the arrangement was not for switcher work, but because Whitcomb simply added two 25 ton locomotives - a proven type - to make a 50 ton one (think of the Sherman with the 4 engines layout). Then if you take a 50 tons Whitcomb and make it a bit bigger, you get a 65 model. It was an incremental design process. So the answer to your question is "serendipity".

To Epaminondas,

Sorry, missed your query. Yes, the van Creveld referred to by Jon G is "Supplying War". Generally speaking, van Creveld seems to have got his numbers from the Italian official histories as well as standard German works of the time. I know of accounts of rail road operations in support of the German eastern front, and can post some references if you're interested but you have to read German because as far as I know they haven't been translated (which is a shame, really: some generals' memoirs are being reprinted in a new translation but a ton of interesting German-language stuff is not translated. Also, the translations into English are often poor editions).

[Jon G.]

Here are some recommendations by AHF member Michate:

- Schüler, Klaus: Der Ostfeldzug als Transport- und Versorgungsproblem. In: Wegner, Bernd (Ed.) Zwei Wege nach Moskau. Vom Hitler-Stalin-Pakt zum "Unternehmen Barbarossa". München 1991, p. 203 - 220
- Kreidler, Eugen: Die Eisenbahnen im Machtbereich der Achsenmächte während des Zweiten Weltkriegs. Einsatz und Leistungen für die Kriegswirtschaft. (= Studien und Dokumente zur Geschichte des Zweiten Weltkrieges, 15) Göttingen 1975

From this post:

http://forum.axishistory.com/viewtopic. ... 152#470152

...unfortunately in German, as Bronsky warned they would be.

[Epaminondas]

thanks!

Sigh, one of these days I'm going to have to sit down and learn german...

[Bronsky]

Sigh, one of these days I'm going to have to sit down and learn german...

Look at it that way. You get 80% off the superb "Germany in the Second World War" multi-volume history and the set comes with better maps as well, and the same is true of other translations (e.g. I browsed the recently-translated English edition of Frieser's book on the campaign of France and not only do English reader get the book 10 years late, they seem to miss the superb maps as well), and then there's all the nifty but untranslated stuff including books like those mentioned above that will likely never be translated as "too dry". So what are you waiting for ?

[JonS]

ESR rolling stock was un-braked, engine or otherwise.

The cars were un-braked and there are various anecdotes in the Italian history where Italian engineers gloat at their German counterparts not taking that bit into account.

The locomotives must have been, otherwise I don't see how the rail line could have been operated at all. That being said, gradient was practically nigligible between Alexandria and El Adem so with that very flat landscape the lack of brakes wouldn't be as much of a problem as in other regions.

Sorry, yes, I didn't make that clear enough. The locomotives obviously had brakes, but the wagons did not. The NZ Rail crews found that took some getting used to (presumably others did too, including obviously the Germans).

as for slope, in general yes: not a problem, and certainly far less of a problem in the WD than say Palestine. However, there was the escarpment SW of Mersa Matruh, as well as local dips and rises, plus the speed and momentum of the train itself. All that made accurate stopping tricky, and emergency stopping very problematic.

[Michael Emrys]

As I wrote, the reason for the arrangement was not for switcher work, but because Whitcomb simply added two 25 ton locomotives - a proven type - to make a 50 ton one (think of the Sherman with the 4 engines layout). Then if you take a 50 tons Whitcomb and make it a bit bigger, you get a 65 model. It was an incremental design process. So the answer to your question is "serendipity".

Curious design process, as I believe there were other diesel-electric engines of the same size class and era that had all the machinery in front of the cab. But then, sometimes things like that happen that way.



Michael

[Jon G.]

...They do all look alike. On another link about the 65 DE 19, the locomotives are described as sometimes having reliability problems, the piston heads being a specific problem. On the other hand, they were good pullers and they could run for a very long time. Also, the type was specifically designed so that the locomotives would be modular i.e. that 2 or more could be coupled for more traction if necessary.

Yes, diesel-electrics of the period were usually constructed so that they could easily be coupled together to form more powerful units as required. It's also an admission of sorts that DEs weren't yet quite as powerful as steam engines, which my long-winded posts on steam engine physics hopefully made clear Would you care to post the second Whitcomb link here?

The multi-coupling option is actually a strong selling point of DEs - if you couple several steam engines together, you will have major power loss and, especially, loss of tractive effort. Power loss from engine to rails is also smaller, and adhesion (the power your engine can yield at the wheels before they begin to slip) is also better in a diesel. The Whitcomb appears to have traction on all wheels, meaning that the full engine's weight can be counted for adhesion, unlike the Stanier, which only has 72.10 tons of its overall weight of 127 tons distributed on its drivers. The rest is essentially dead weight for tractive purposes.

Finally, top speed of the 65 DE 19 is given at 45mph, fast for a military locomotive of the time. Assuming that this is the same type that the French received as Marshall aid, then the French number of 65 km/h (~41mph) being lower isn't really surprising for a second-hand machine...

That's a point, but then rated speed is often not the same as real speed. At 45 mph, I would think that the speed limit set by the quality and weight of the track and its ballast, and particularly the absence of brakes on the train, would become a factor well before the DE hit its top speed.

[Bronsky]

Yes, diesel-electrics of the period were usually constructed so that they could easily be coupled together to form more powerful units as required. It's also an admission of sorts that DEs weren't yet quite as powerful as steam engines, which my long-winded posts on steam engine physics hopefully made clear

It did, the only thing that isn't clear to me is how much of a factor it was in practice. In other words, given that my own background is economics instead of physics, I tend to ask "how many ton-miles can locomotive X pull" instead of "how much strength is applied the piston of locomotive X".

Not to say that your demonstration wasn't interesting (it was to me), but from my point of view it's not clear that the steam locomotives were more "powerful" (per the definition above) than the diesel ones.

Would you care to post the second Whitcomb link here?

http://www.jeff-z.com/wks/locoroster/602/rhp.html

The multi-coupling option is actually a strong selling point of DEs - if you couple several steam engines together, you will have major power loss and, especially, loss of tractive effort. Power loss from engine to rails is also smaller, and adhesion (the power your engine can yield at the wheels before they begin to slip) is also better in a diesel. The Whitcomb appears to have traction on all wheels, meaning that the full engine's weight can be counted for adhesion, unlike the Stanier, which only has 72.10 tons of its overall weight of 127 tons distributed on its drivers. The rest is essentially dead weight for tractive purposes.

One Whitcomb has 65 tons for adhesion and 0.2 ton dead weight (fuel). One Stanier has 72 tons for adhesion and 55 (locomotive) + 9 (coal) + 19 (water) = 83 tons of dead weight, plus the fact that it must stop more often and is more maintenance-intensive (a characteristic of all steam locomotives). I have no idea which one comes up ahead.

Finally, top speed of the 65 DE 19 is given at 45mph, fast for a military locomotive of the time. Assuming that this is the same type that the French received as Marshall aid, then the French number of 65 km/h (~41mph) being lower isn't really surprising for a second-hand machine...

That's a point, but then rated speed is often not the same as real speed. At 45 mph, I would think that the speed limit set by the quality and weight of the track and its ballast, and particularly the absence of brakes on the train, would become a factor well before the DE hit its top speed.

Yes, I posted that as a data point showing that the initial set of specs seemed on target.

[JonS]

Here we go, quoting and contradicting myself :roll:

Oh, BTW, the Western Desert Rail extension was ballasted. The sleepers and rails were initially laid straight onto the desert by one of the Railways Construction Companies. The second RCC was following along behind lifting the track and ballasting it, as well as building all the other infrastructure needed for a rail line. Laying then lifting-and-ballasting seems an odd way of doing things to me, but then I know about this much -->| . |<-- about laying track ...

I was reading the NZ Engrs OH last night, with a view to rounding out what was in The Desert Railway. The OH gives the sequence as Forming - Laying - Tidying Up. Forming includes all the earthworks necessary to lay tracks on the surveyed route, and might include culverts, cuttings, and did include ballasting. Laying was just the laying out of sleepers and bolting-on of track. Tidying Up included building up the infrastructure, and could include re-ballasting where required.

Linky-poo. The relevant is from about page 170 onwards.

Jon

[Bronsky]

Linky-poo. The relevant is from about page 170 onwards.

Actually, I had read the whole thing when it was posted the first time but had missed some of the technical stuff. What I noticed was how in the case of the New Zealanders, too, the bottleneck was supply of equipment and particularly tracks, not manpower. There are various points where the diaries read something like "we laid all the track we had so stopped working for the rest of the day".

At this point, I would be really interested in an account of tonnages shipped and unloaded from the British end. So far, I've found that this was a very complex question because whereas Axis convoys are relatively straightforward (from Europe to North Africa and back), the British were optimizing shipping space by running ships from Britain to the Middle East but also "sideways" e.g. a ship sent from Britain to India would often transport equipment and personnel to the Middle East, and might make additional round trips between Egypt and South or East Africa (or Aden, or Iraq...) before heading home. Similarly, ships heading to Egypt would often be engaged in other duties before sailing back. Also, they would sometimes stop in, say, South Africa where they would unload some of their cargo, pick up something else and sail to Egypt. Only the US convoys look relatively straightforward.

[Jon G.]

Yes, diesel-electrics of the period were usually constructed so that they could easily be coupled together to form more powerful units as required. It's also an admission of sorts that DEs weren't yet quite as powerful as steam engines, which my long-winded posts on steam engine physics hopefully made clear

It did, the only thing that isn't clear to me is how much of a factor it was in practice. In other words, given that my own background is economics instead of physics, I tend to ask "how many ton-miles can locomotive X pull" instead of "how much strength is applied the piston of locomotive X".

Not to say that your demonstration wasn't interesting (it was to me), but from my point of view it's not clear that the steam locomotives were more "powerful" (per the definition above) than the diesel ones...

In the final analysis there can be little doubt that the Whitcombs beat the Staniers by a handsome margin for operations on the desert railroad. After all, power output is just one parameter for measuring a locomotive's usefulness for the task at hand. Logistic requirements - in casu the voracious water needs of the Stanier - reliability and also availability are just as important factors. After all, there were no Whitcomb DEs around when the desert railroad opened operations, and the Whitcombs eliminated water needs at a stroke. It also seems that the desert railroad was built and planned with sufficiently generous loops and sidings to allow for denser traffic if needed - i.e. more, but smaller trains could be scheduled if standard Stanier train loads were too much for the Whitcombs to handle.

The Allied-operated Persian railroad which I linked to earlier may be a useful comparison. It compares fairly well with the desert railroad chronologically, but on the Iranian line bulk was what mattered. Hence, powerful (by all standards) US Mikado engines were supplied to the Iranian railroad, and hence we may deduce that in strict physics terms the steam engine was still superior to the diesel-electric engine during WW2, even if the margin was closing hastily in the DE's favour.

Alco DEs were also supplied to the Persian line, but it appears that this was due to the specific problems posed by long tunnels, in which steam engines lose their breath before diesels do.

As far as I know, the vast majority of train engines supplied to the Soviet Union via Lend-Lease were steam engines. Better to supply an engine type guaranteed to be useful, which the crews are used to operating, and for which the coal and water infrastructure is already in place, rather than a brand new engine type.

Snip, and thanks for the Whitcomb link.

One Whitcomb has 65 tons for adhesion and 0.2 ton dead weight (fuel). One Stanier has 72 tons for adhesion and 55 (locomotive) + 9 (coal) + 19 (water) = 83 tons of dead weight, plus the fact that it must stop more often and is more maintenance-intensive (a characteristic of all steam locomotives). I have no idea which one comes up ahead...

Power applied at the rails probably still comes out in the Stanier's favour, but in order to calculate exact tractive effort and train resistance we also need to know which gradients the trains were expected to meet and which train weights the engines were supposed to pull. With fuel weight reduced by a factor of ~140 the somewhat reduced traction of the Whitcomb is hardly an issue in the larger picture.