Relative size of combatants

Several points --

Astelon wrote:The risk to the men is one thing, risks to millions of marks worth of equipment is another. Lowering one giant crane to a manmade platform so you could dangle even more equipment from that crane to build an even lower platform is a serious risk to all of that equipment.

As for talents, a telekinetic has a forty pound maximum lifting ability. Not going to make much of a difference. As for the mappers, we have seen how a Plotter scanning for life near a portal gets interference from the "portal energies" (Hell's Gate chapter eighteen). A Mapper probably faces a similar problem, making the talent of less use around a portal.

Further there is no mention of any ropeway in the story, likely there is no ropeway at all.

1. RFC leaves a lot of stuff "off camera" to maintain flexibility with story writing.

2. Given that the Traisum Cut is based on a railway cut out in New Mexico, he has to know the history of it's construction. And his TTE heavy railway engineer are using equipment similar to that effort. He is very much aware of cable excavators and other applications of railway specific cableway/ropeway technology.

[FYI, I was driving through that New Mexico railway cut in 2007 shortly after I read Hells Gate and _recognized the terrain there from the descriptions from the book_.]

3. You seriously underestimate the productivity and safety boost of the T-K talent for moving things like pitons, hot rivets and other small but vital fasteners in civil engineering or high rise type construction.

NB: Over 100 workers died in the construction of the Hoover Damn. Many were fall victims transiting back and forth getting those many small fasteners, and even trivial things like lunches.

There are a lot of people who work thousand foot high BASE towers for cell phones and microwave telephone transmission who would kill for someone able to sent them a few fasteners, electrical or electronic components at a time to do their very dangerous jobs.

I agree.
That's why I haven't joined this discussion.

HTM

PeterZ wrote:[snip - htm]
Now, whether there is a ropeway in the Traisum Cut
depends on whether RFC thought about it or not.
Its that simple. MTB pretty much showed that
the project was possible.

What is the name of that New Mexico railway cut -- I'd like to see some pictures of it.

tonyz wrote:What is the name of that New Mexico railway cut -- I'd like to see some pictures of it.

Look up the Raton pass in New Mexico.

In the late 19th century, Raton Pass was used by the Atchison, Topeka and Santa Fe Railway as the railroad's primary route through the mountains.

I took I-25 south from Colorado in 2007 and the interstate and the old Santa Fe Transcontinental rail lines were next to each other in the area of the Pass.

According to Wikipedia --

"The route over the pass required gradients of up to 3.5%, with a tunnel at the highest point of the Santa Fe Railway (The tunnel is entirely within New Mexico, with its northern portal only a few feet south of the Colorado border).[4]"

Mil-tech Bard,

Wrong. I am -NOT- ignoring the capabilities you listed. Either you aren't understanding my arguments, or you are reading very different information from your quotes than I am.

1. "In 1911, aerial ropeway lines were typically 1,000 to 15,000 feet (305 to 4,600 metres) long, with a daily cargo capacity of 15 to 200 tons and speeds of around 2 to 5 mph (3,2 to 8 km/h)."

The ropeway line length is the the total length of each section/loop of the cableway; it is NOT the unsupported length of rope. The longest unsupported length ever built was 11,367 ft, built in 1979: https://en.wikipedia.org/wiki/Feldmoos-Chli-Titlis_Aerial_Tramway. It could carry only a single 3.8 ton load at a time (the longer the span, the less it can carry because of the weight of the rope itself). And the materials available in 1979 were very different than the ones available at the turn of the 20th century.

2. "The fall was between zero (almost horizontal lines) and 4,000 feet (1,220 metres)."

The fall is the total altitude change from one side to the other. High altitude changes are absolutely possible. They say nothing about the number of towers used over that fall or the unsupported length of the ropes.

3. "Ropeway towers could be constructed from timber or iron and were generally between 100 and 300 feet (30 to 90 metres) apart, although much longer spans were possible if necessary."

Yes, longer spans without towers were possible. I never said they were limited to the 300 feet mentioned here. But longer than 300 feet does NOT equal 4200 or 6200 feet.

Your link was interesting and informative, but it never made any claims for major unsupported lengths at Sharonian tech levels. As I said in my last post, a cableway that hugs the cliff and has multiple supports on the way down is possible. One that has NO supports on the way down probably is not, because we never built one with that unsupported length at their tech level.

But I agree that what kind was possible matters far less than whether or not the authors decided to put one in.

Mil-tech bard wrote:bkwormlisa,

You are -STILL- not paying attention to the known ropeway capabilities of 1911.

See:

1. "In 1911, aerial ropeway lines were typically 1,000 to 15,000 feet (305 to 4,600 metres) long, with a daily cargo capacity of 15 to 200 tons and speeds of around 2 to 5 mph (3,2 to 8 km/h)."

2. "The fall was between zero (almost horizontal lines) and 4,000 feet (1,220 metres)."


3. "Ropeway towers could be constructed from timber or iron and were generally between 100 and 300 feet (30 to 90 metres) apart, although much longer spans were possible if necessary."

TRIGONOMETRIC FUNCTION ANALYSIS

A 30 degree ropeway downslope -- AKA a classic TRIGONOMETRIC 30-60-90 triangle -- with a 3100 foot (1000 meter) "opposite" for the cliff height results in a ropeway hypotenuse of twice the 3100 foot height, or 6,200 feet (~2000 meters).

A ropeway over the Traisum cliffs represents 41% of the 1911 Ropeway technological state of the art cable-rope length and 82% of 1911 state of the art in ropeway drop over distance.

The TTE can easily double the length of the cable-rope to buy a less steep ropeway down angle.

See:

A^2 + B^2 = C^2

Where

A= 3,100
B= ?
C= 12,400

Yeilds B = 12,006 feet away from the angle/tension tower at the top of the cliff.

A three stage elevator down the side of the cliff (AKA 1000 feet to a significant cliff anchored platform, then another 1000 feet to a significant cliff anchored platform, then an elevator to the bottom) would give you the means to transport down people and supplies to build the ropeway.

You could either use the "significant cliff anchored platform" as a "tower" or angle-tension station against cliff for a zig-zag ropeway.

Or simply angle away from the cliff at the top, accepting more sway in the cable rope.

NB: A ropeway over the Traisum cliff is a trivial intial enabling step for the TTE Civil Engineer Corps given the successful accomplishment of the cut in the first instance.

The images of Raton Pass look nothing like I imagine the Traisum Cut to be like. You and I must have very drawn very different conclusions from descriptions of the cut.

Regards this Astelon --

Astelon wrote:The images of Raton Pass look nothing like I imagine the Traisum Cut to be like. You and I must have very drawn very different conclusions from descriptions of the cut.

The difference between you and I is that you are looking at terrain, I am looking at TRAINS.

A portal that causes hurricane force winds for a century, flash floods, glaciers and 3,000 foot cliffs that a world spanning civilization cuts a rail line through means, Terrain wise, we are looking at something in RFC's writing that is like nothing on this earth.

As far as trains and railway infrastructure are concerned, that is very much a different kettle of fish.

RFC (like most authors) shows off all the research he has done in his tech bibles for the books he writes. He's really good at it and that is why so many of us geek out at it on the forums here.

This however, leaves patterns in his writing where you can sometimes see where he filed the serial numbers off in his historical research.

Regards recognizing the Raton Pass in the Traisum Cut, go to the first three pages of chapter 42 in Weber and Evan's HELLS GATE.

Specifically see the discussion between Division-Captain chan Geraith and the TTE Trainmaster Yakhan Chusal while loading is being done for chan Geraith's first train to Traisum. This is the passage where the Transport Tractor, Mark I, Model B, AKA "Bisons" are being loaded.

There is an author exposition through Trainmaster Yakhan Chusal on articulated versus extended cargo rail cars and the transportation obstacles between Sharona and Traisum. Chusal mentions the need to use articulated cars for modular ship sections, and how on the last rail line after the final water gap that the articulated train cars cannot "make the curves or rail line weights where chan Geraith is going", AKA the Traisum Cut.


Now, after reading that passage, please go back and look at the pictures of the rail line curves from the Raton Pass.

Bkwormlisa,

Regards your final point here:

Yes, longer spans without towers were possible. I never said they were limited to the 300 feet mentioned here. But longer than 300 feet does NOT equal 4200 or 6200 feet.

Your link was interesting and informative, but it never made any claims for major unsupported lengths at Sharonian tech levels. As I said in my last post, a cableway that hugs the cliff and has multiple supports on the way down is possible. One that has NO supports on the way down probably is not, because we never built one with that unsupported length at their tech level.

But I agree that what kind was possible matters far less than whether or not the authors decided to put one in.

We have all missed an important point that RFC laid out in HELLS GATE.

The Traisum Cut was completed without a railway line.

See Hell's Gate Chapter 34, pages 456 thru 459.

There is a conversation between Crown Prince Janaki and Voice Kinlafia about the latter going ahead through Ft. Salby to Sharona to become a politician.

In it they lay out the following --

1. The TTE train line did not reach the Traisum cut until well after it was completed.

2. It gives a background on the horse trail/road from Traisum to Hells Gate.

3. Sharonan military's have wagons with well spring pneumatic rubber tires together with damned fine hippotrain to pull them (Ternathian Cavalry mounts were mentioned earlier with Janaki Uber-Lippizoner).

Given #1 above, RFC has pretty much written himself into a corner that only something like a ropeway placed to support the Traisum Cut -- prior to the rail line arriving -- is the only way I can see the Sharonan's pulling off the Cut in less than a decade...

...in which case the railway would have gotten there prior to the Cut being completed in any case.

Moving tens of thousands of tons of gun cotton, nitro or early dynamite explosives across hundreds of miles by hippotrain -- well sprung shocks and pneumatic tires notwithstanding -- is counter-indicated.

Mil-tech bard wrote:As there were no such things as fairly sophisticated tension controls for 1860's-1930's ropeways, and they worked out just fine, I don't see an issue here.

Jonathan_S wrote:Without fairly sophisticated tension controls having towers sticking out the side of the cliff holding a near vertical cable don't help with the "elevator problem" because they can't revive the upper cable of the need to support the entire weight of the lower cable (plus the weight of the cargo)

When you run a lengthy fairly horizontal cable across a series of vertical supports they each take some of the weight and the cable need only support the load and the weight of the cable between any two adjacent towers.
But with a vertically hung cable the intermediate towers just hold it away from the cliff. They don't transfer the vertical force into the rock; that's all done at the top tower/anchor.

Before I dive off into the technical details, I want to say a couple things:

1) We have no evidence of a pre-existing ropeway system used during the excavation of the gap. And as they came in from the side it's possible that they didn't need one; they could have kept blasting the rocks down into the slowly lengthening cut then hauling them out on the road they were cutting.

2) Your later post finally let me understand one of your proposals, and see it would be technically possible to construct a ropeway running horizontally but parallel to the cliff face.
But if one doesn't already exist I doubt it's easier or safer to construct one, while Arcana holds the far side of the portal, that is it to secure the gap. And after securing that road and railway you don't have need to construct a ropeway down.


Now onto the technical details:
The amount of weight a ropeway can move between two towers is a function of the cable angle between then. At nearly horizontal angles the entire weight of the cargo transfers to the heavy fixed cables than run between towers. As they don't move they can be easily tensioned so that the towers takes the entire force and it isn't transferred to rest of the cable. The fixed cables to sag some, so the moving cable need to impart enough force to not just overcome friction, but to drap the load up angle of the cable's sag into the next tower; however the force required is still quite low.

But as you increase the cable angle less and less of the weight transfers into the fixed cables and more and more has to be taken by the moving cable. And what's worse, the moving cable can't be easily tensioned at each tower so it ends up carrying an increasing fraction of it's own weight as well as the increasing fraction of the cargo weight.

The corollary to that is that the steeper the ropeway the less weight it can carry. And as it goes past 45-50 degrees it begins to act more like an elevator rather than a ropeway.
But that force transfer vs angle is also why for a given tech level an elevator will always have to be shorter and/or carry less payload than a more horizontal ropeway.

Now you can lessen the rise angle by pushing the support tower further back; but at some point you run into a crossover point where the total suspended mass of the cable segment becomes too much and making it longer to flatten out the slope no longer helps and begins to hurt. (Unless you can break it into two segments by installing an intermediate tower to terminate the fixed cable segments at)


But all this means that unless you can show how the terrain allows for the necessary slope and support towers you can't just point to ropeways in general and claim they can work in any particular situation (much less that ropeways of a given length prove you can have elevators of that length)


For instance your earlier suggestion that you could just have a ropeway sticking out perpendicular from the cliff. That would have required a base tower at least 3000 feet out from the base of the cliff, with the terrain offering no practical spot for intermediate towers. This results in a 4500+ foot long, unsupported, cable segment rising at roughly 45 degrees; which appears to be excessively long for that angle of fall.

nitpick: chan Geraith is going to Traisum Cut
*by way of the approaches to it through Salym
and Traisum,* not merely to TC itself.

The need for "articulated" instead of "extended"
railroad cars might apply to any place along the
whole route, not just TC itself.

Recall that the route through Salym includes a
railroad running from "Durres" to "Sofia" in the
"Balkans" which is a mountainous route with many
curves. Trainmaster Chusel might have been talking
about that, even if the TC is a straight line.
-------------------
On your other topic,
building TC sans railroad support,
I figure that cargo ships carried the heavy
equipment and other supplies from the railhead
(then in "Ethiopia/Somalia/Eturia") to the nearest
point to TC on the "Red Sea" coast.

Further note: since SPA built a shipyard on the
Mediterranian, I wonder if they built a "Suez Canal"
to bring ships to Finger Sea without having to make
another shipyard there.

HTM

Mil-tech bard wrote:{big snip - htm}

go to the first three pages of chapter 42 in Weber and Evan's HELLS GATE.

Specifically see the discussion between Division-Captain chan Geraith and the TTE Trainmaster Yakhan Chusal while loading is being done for chan Geraith's first train to Traisum. This is the passage where the Transport Tractor, Mark I, Model B, AKA "Bisons" are being loaded.

There is an author exposition through Trainmaster Yakhan Chusal on articulated versus extended cargo rail cars and the transportation obstacles between Sharona and Traisum. Chusal mentions the need to use articulated cars for modular ship sections,

*and how on the last rail line after the final water gap
that the articulated train cars cannot "make the curves
or rail line weights where chan Geraith is going",*
AKA the Traisum Cut.

{small snip - htm}