Talgo Coach vs. Turbo Train Coach

I asked this question on another site and thought I'd ask it here too.

I have always wondered why Talgo doesn't make their coaches longer. The original Turbo Train coaches were approximately 57' long and the present Talgo coaches are only 43' long. A 60 foot coach design would be much more efficient then the 43 foot coach design that they now use. For instance the "new" Wisconsin Talgos are 13 cars long which could maybe be only 9 cars long eliminating the weight and maintenance of additional wheels and connecting mechanicals and support structures. They also could eliminate 8 doors and 4 extra vestibules which saves substantial space. The present design seems like door overkill to me.

To increase capacity with the new Avril model, Talgo has finally maxed out the width to about 10' 5" but the obvious easy solution to extend the length has still not been tried. Why not? Just puzzles me.

Below the original Turbo Train 57' coach and the newer 43' design:

bostontrainguy wrote: ↑Tue Dec 17, 2019 6:28 pm I asked this question on another site and thought I'd ask it here too.

I have always wondered why Talgo doesn't make their coaches longer. The original Turbo Train coaches were approximately 57' long and the present Talgo coaches are only 43' long. A 60 foot coach design would be much more efficient then the 43 foot coach design that they now use. For instance the "new" Wisconsin Talgos are 13 cars long which could maybe be only 9 cars long eliminating the weight and maintenance of additional wheels and connecting mechanicals and support structures. They also could eliminate 8 doors and 4 extra vestibules which saves substantial space. The present design seems like door overkill to me.

To increase capacity with the new Avril model, Talgo has finally maxed out the width to about 10' 5" but the obvious easy solution to extend the length has still not been tried. Why not? Just puzzles me.

Below the original Turbo Train 57' coach and the newer 43' design:

20120910-Turbo-Workshop.jpgligeros_OK-2.jpg

There are two basic answers to your question.
(1) Talgo cars are supported between two axles, weight limitations per axle limit the size, therefore length, of each car. And those axles feel the weight of both cars it is nestle between.
An Amfleet coach would have twice as many axles and don't feel the weight of adjacent cars and therefore should easily carry twice as much weigh.
(2) Car clearances to rail side structures. A standard 85 feet long coach place their truck center-posts which contain the axles and wheels about 12.5 feet back from the end, so 25 feet of the 85 feet long coach is extended beyond, leaving an effective wheel-span around 60 feet. Talgo places their wheels (or axles) at either end of the car, not under them. While 60 feet is longer than 43 feet, so the clearances to railside structures on the inside of curves should be okay. A longer 85 feet long Talgo with wheels at the ends would have trouble with clearances, although a 60 feet long car or less shouldn't.

Since the weight limitation per axle forces the cars to be shorter, that's is the main reason why they are so short.

Yeah, I thought about those same issues. But the Turbo Train had a similar single axle/pendulum suspension at 57 feet so the weight thing probably isn't a problem. I'm guessing the Talgo cars are pretty light.

And of course a 57 foot car with single articulated axles easily fits within the 60 foot "wheelbase" of a standard 85 foot coach, so the length isn't an issue either.

I think it could be done and just don't understand why Talgo doesn't maximize the size and efficiency of their coaches.

I've had the same question. The original UA Turbo and the original TGV both had single axle articulated trucks between longer coaches than Talgo.

Talgo cars are shorter than CTA cars, could go around a heck of a curve if they weren't articulated.

bostontrainguy wrote: ↑Wed Dec 18, 2019 12:08 am Yeah, I thought about those same issues. But the Turbo Train had a similar single axle/pendulum suspension at 57 feet so the weight thing probably isn't a problem. I'm guessing the Talgo cars are pretty light.

And of course a 57 foot car with single articulated axles easily fits within the 60 foot "wheelbase" of a standard 85 foot coach, so the length isn't an issue either.

I think it could be done and just don't understand why Talgo doesn't maximize the size and efficiency of their coaches.

The more modern Talgo cars built to tougher crash standards might be heavier than the old Turbo train, but without a complete set of technical specifications, I can only speculate. A 2 axle at 57 feet is around 20 feet shorter than a typical 4 axle car. The more modern Talgo cars are just 10 feet or so shorter.
Also, a similar articulated single axle design is probably not the exact same design, so maybe the newer design can not carry as much weight. But I pretty sure that if the new Talgo design could carry more weight, the cars would be longer than they are.

Talgos are built to European specs? Are European railroads curvier or have station platforms that are curvier? Or tracks that are closer together?

Just a little more food for thought. This is a pic of the four unit "Talgo 22" prototype. Since this is a huge bi-level design it would seem to squash the weight limitation on the Talgo single axle bogie.
There was a "Talgo 22" brochure printed that had the specs and the interim cars were listed as being up to 9 meters long (29.5 feet):

https://www.yumpu.com/en/document/view/ ... 1/talgo-22

So for the sake of this argument, I do not believe weight is a factor in the car length of the single-level Talgo coaches.

BTW - The "Talgo 22" was revolutionary being a true bi-level train with pass throughs on both levels but as far as I can investigate, Talgo never went further than the building of a prototype for the Talgo 22.

Maybe the length has to do with transport?... Minus draw bars and suspension gear, it sounds like the rest of the shell might fit in a standard shipping container frame.


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bostontrainguy wrote: ↑Fri Feb 07, 2020 5:39 pm Just a little more food for thought. This is a pic of the four unit "Talgo 22" prototype. Since this is a huge bi-level design it would seem to squash the weight limitation on the Talgo single axle bogie.

There was a "Talgo 22" brochure printed that had the specs and the interim cars were listed as being up to 9 meters long (29.5 feet):

So for the sake of this argument, I do not believe weight is a factor in the car length of the single-level Talgo coaches.

Talgo single level length being 43 feet, double level length being 29 feet, and you suggest weight is not the cause for the shorter lengths? Golly, 29 feet is 67% of 43 feet. What other possible reason is there for the missing 33% besides reducing weight?

Off hand, one might assume doubling one dimension (height in this case) would cause a doubling of the weight. But in a hollow rectangle, that is not true. If the width and length were the same, doubling the height does affect weight, but not by 100%. Shrinking the length by 33% balanced increasing the height by 100% at least by the dimensions of the finished prototype.

For comparison’s sake, three Talgo 22s would be about 87’ long. That’s comparable to a single 85’ Superliner, but with one less axle and considerably more capacity. Would be interested to see the relative axle leadings.

bostontrainguy wrote: ↑Fri Feb 07, 2020 5:39 pm Just a little more food for thought. This is a pic of the four unit "Talgo 22" prototype. Since this is a huge bi-level design it would seem to squash the weight limitation on the Talgo single axle bogie.

TALGO 22.jpg

There was a "Talgo 22" brochure printed that had the specs and the interim cars were listed as being up to 9 meters long (29.5 feet):

https://www.yumpu.com/en/document/view/ ... 1/talgo-22

So for the sake of this argument, I do not believe weight is a factor in the car length of the single-level Talgo coaches.

BTW - The "Talgo 22" was revolutionary being a true bi-level train with pass throughs on both levels but as far as I can investigate, Talgo never went further than the building of a prototype for the Talgo 22.

Food for thought, but a different thought entirely. I now wonder if I can get a decent sleeper on a 43' long car...

electricron wrote: ↑Sat Feb 08, 2020 11:58 pm
Talgo single level length being 43 feet, double level length being 29 feet, and you suggest weight is not the cause for the shorter lengths? Golly, 29 feet is 67% of 43 feet. What other possible reason is there for the missing 33% besides reducing weight?

Well actually Talgo says right in the brochure that reducing the length allowed them to increase the width for greater capacity. Note that these cars are approximately 10.5 feet wide and check out the 5 across seating in the pics just like the new Avril model. So these cars are shorter but wider and still hold about the same number of passengers.

I know what you are saying and I did consider it. However, I also took into consideration that ROUGHLY the bi-level has double the seats of a single level coach. So you are doubling the passenger load. That's a 100% increase in passenger weight.

Talgo states that their coaches can hold up to 54 passengers which would approximate a passenger load of 10,152 pounds (using FAA estimates of 188 pounds average for passengers with luggage). So a double decker standard car would approximate a passenger load of 20,304 pounds. On the other hand, adding an extra 40% passenger load by extending the length (43 feet to 60 feet) would total only 14,212 lbs.

So this is certainly not scientific but I think that all has to be considered. Don't know the exact technical details, but I would think Talgo could do it even if they had to beef up their bogies a bit.

STrRedWolf wrote: ↑Sun Feb 09, 2020 9:22 am

bostontrainguy wrote: ↑Fri Feb 07, 2020 5:39 pm Just a little more food for thought. This is a pic of the four unit "Talgo 22" prototype. Since this is a huge bi-level design it would seem to squash the weight limitation on the Talgo single axle bogie.

TALGO 22.jpg

There was a "Talgo 22" brochure printed that had the specs and the interim cars were listed as being up to 9 meters long (29.5 feet):

https://www.yumpu.com/en/document/view/ ... 1/talgo-22

So for the sake of this argument, I do not believe weight is a factor in the car length of the single-level Talgo coaches.

BTW - The "Talgo 22" was revolutionary being a true bi-level train with pass throughs on both levels but as far as I can investigate, Talgo never went further than the building of a prototype for the Talgo 22.

Food for thought, but a different thought entirely. I now wonder if I can get a decent sleeper on a 43' long car...

Oh yeah . . . already done: https://www.yumpu.com/en/document/read/ ... rain-talgo

bostontrainguy wrote: ↑Sun Feb 09, 2020 12:39 pm Oh yeah . . . already done: https://www.yumpu.com/en/document/read/ ... rain-talgo

Ooooh nice. The first class sleeper is what I was expecting for a more modern sleeper. Although, it made me wonder about a double-decker apartment.

Anyway, enough off-topic stuff.

I don’t mind the semi-OT stuff. We’re still discussing the construction of Talgo cars, and I would love if we also brought in more about the Turbo’s construction, because I have a feeling it’s more akin to a jet than a railcar.