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Relative size of combatants

"Hell's Gate" and "Hell Hath No Fury", by David, Linda Evans, and Joelle Presby, take the clash of science and magic to a whole new dimension...join us in a friendly discussion of this engrossing series!
Re: Relative size of combatants
Post by Mil-tech bard   » Mon Jul 20, 2015 10:11 am

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Jonathan_S,

This:

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.
[/quote]


...is one of those places we are going to have to disagree.

The most important point here is the text says no railways were used in the construction of the cut.

The railway came after the cut was complete.

So if there are no railways, there was no way to deliver to the cut the huge TTE cranes, steam shovels and other equipment extended and articulated rail cars can deliver.

That leaves something else.

Now some of the links to photos and slides of the most likely something else -- ropeways and cable ways. The following are examples of both heavy construction and as transportation --

1. Ropeways in heavy duty civil engineering from the LCS Cable Cranes web site.

Material Ropeways

http://www.lcs-cablecranes.com/transpor ... l-ropeway/

The rotating photos at the link above shows the application of the technology to mountainous heavy duty civil engineering. The photo of the ropeway digging out of a mountain cut is spot on for Traisum applications.

This is the accompanying LCS promotional text --

Ropeways to enable construction sites

Our cable cranes show a clear advantage for all complex construction sites – where access for heavy machinery to deliver tons of construction material and construction equipment is almost impossible.

Difficult terrain that can be opened only with large time and financial expenses building access-roads, but could reached quickly and cost-effectively through the use of our systems.

Material ropeways do not only allow a quick and safe transportation of goods to the designated points, but permit a continuous operation schedule 24/7 on throughout the whole year.

Material cable-cranes are applicable in all sorts of geographical locations – high mountains, forest, over rivers, lakes or other landscapes, but as well in all kind of climatic conditions – from snowy mountains, to rainforests and dry deserts. They can be used for almost all kind of construction sites: mountain construction sites, pipeline construction, bridge construction and in forestry.

A material ropeway is ideal for operations where a safe, fast and above all efficient transportation of heavy loads is required.



2. From the "howtopedia" the Construction of Aerial Ropeways in Nepal


Construction of Aerial Ropeways - Nepal

See Figure 6 for a photo of a small Hydro-powered ropeway transport system with a guyed tower.

http://en.howtopedia.org/wiki/Construct ... ys_-_Nepal

3. A paper from the Nepal Ministry of Peace and Reconstruction.

Paper on Graduating Upwards from Suspension Bridges to Ropeways and Cable Cars:
Nepal's Experience and Expertise
by Bhim Updhyaya
23 Nov 2014

See the photos in slides 24 thru 32 of the presentation and in particular several examples of exceedingly long cableways without intermediate towers, guyed or otherwise.

http://www.slideshare.net/BhimUpadhyaya ... m-updhyaya


4. The Seti River Ropeway, 450 meter length, no intervening towers

Mechanized Bridge (River Crossing Passenger Ropeway)

http://www.gridnepal.org.np/project_det ... ion-c.html


It is a bicable bidirectional type of ropeway technology operates under motor power design and builds by the engineers of Nepal using locally available materials. The system is installed as prototype for human transportation connecting Kotre, Tanahun and Punditar, Kaski over Seti River having 520m with 25m level difference. At that section, numerous efforts of bridge construction was in vain due to technical infeasibility. So ropeway technology for river crossing is the best at such long span. The technology is also economical considering construction as well as operation cost for the span greater than 450 meters.
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Re: Relative size of combatants
Post by brnicholas   » Mon Jul 20, 2015 12:55 pm

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The statement that the railway did not reach the cut until it was completed is either a misunderstanding of a text on our part or a continuity error on David and Linda's part. While their are a couple of texts which imply that the railroad didn't reach Fort Salby until after first contact with the Sharonans it is clearly established and a major plot point that all the sidings used to hold railroad cars and equipment while the cut was being dug and Fort Salby was the end of the rail line are still at Fort Salby!

From the prologue of Hell Hath No Fury, "the remaining buildings of Salbyton had a look of permanency and solidity which was rare this far from Sharona, and the local railroad station had quite literally miles of heavyduty sidings left from its days as the end of the TTE's line."

From Chapter 32 of Hell Hath No Fury, "Chan Geraith had seen the endless lines of work cars, portable machine shops, flatcars loaded with bulldozers and scrapers, passenger cars, portable sawmills, auxiliary steam engines, loads of unused rails and ties, bolts, spikes, hammers, pickaxes. . . . The list seemed endless, and the cars and work locomotives filled the extensive sidings left behind when TTE finished construction of the Traisum Cut almost to capacity."

Nicholas
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Re: Relative size of combatants
Post by tonyz   » Mon Jul 20, 2015 1:10 pm

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We should note that one of the implications of this statement is that the line as completed has plenty of sidings and so forth along it, or they wouldn't have been able to move all that stuff in and out along the line -- shipping new rails and ballast up, rearranging works trains, and so on. Some of this could have been done if the line was double-tracked all the way (which it may be), but I expect quite a few little sidelines, work stations, etc., got built into the line as it advanced.
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Re: Relative size of combatants
Post by Mil-tech bard   » Mon Jul 20, 2015 3:03 pm

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brnicholas,

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

The TTE Railways arrival at the Traisum Cut long after the Sharonan survey team is wiped out and avenged isn't implied.

It was both stated as fact by the Calirath Crown Prince Janiki and is a major plot point to push Voice Kinlafia to Sharona -- to be a politician and protector of Janiki's sister per Janiki's Glimpse -- before the attack on Ft Salby.


brnicholas wrote:The statement that the railway did not reach the cut until it was completed is either a misunderstanding of a text on our part or a continuity error on David and Linda's part. While their are a couple of texts which imply that the railroad didn't reach Fort Salby until after first contact with the Sharonans it is clearly established and a major plot point that all the sidings used to hold railroad cars and equipment while the cut was being dug and Fort Salby was the end of the rail line are still at Fort Salby!

From the prologue of Hell Hath No Fury, "the remaining buildings of Salbyton had a look of permanency and solidity which was rare this far from Sharona, and the local railroad station had quite literally miles of heavyduty sidings left from its days as the end of the TTE's line."

From Chapter 32 of Hell Hath No Fury, "Chan Geraith had seen the endless lines of work cars, portable machine shops, flatcars loaded with bulldozers and scrapers, passenger cars, portable sawmills, auxiliary steam engines, loads of unused rails and ties, bolts, spikes, hammers, pickaxes. . . . The list seemed endless, and the cars and work locomotives filled the extensive sidings left behind when TTE finished construction of the Traisum Cut almost to capacity."

Nicholas


Nothing in the passage above necessarily makes the Hell's Gate passage a "continuity error", as "completion of the RAILWAY" was not given a date.

Hell's Gate makes clear that the TTE railway had not reached Salbyton until months after the Andaran Scouts wiped out the Sharonan survey team, and the PAAF wiped out the Andaran Scouts in turn.

The heavy civil engineering of removing the rock in the Traisum Cut, to have a workable railway grade through the mountain, happened before the railway arrived.

That this is not the sequence I'd logically expect does not change the fact this sequence is tightly tied to a major plot point to get Voice Kinlafia to Sharona before the attack on Ft. Salby.
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RR 2 Traisum Cut was: Relative size of combatants
Post by Howard T. Map-addict   » Mon Jul 20, 2015 5:10 pm

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Mil-Tech Bard, BR Nicholas, and others concerned:

I have a way to reconcile the variant textev.

I figure that the Main Line of the TTE was slowly
moving from the Salym Gate to the "Arabian Sea"
(in competition with the other TTE line direct to
the Mbisi), while at the same time "Cut Material"
was moved from Salym Gate to Karys Gate,
first by rail to the "Somalia" Seacoast,
**then by ship to a port such as "Jidda,"**
and then inland to the KG for the TC.
The route from "Jidda" to Salbyton would have been
for walkers and horses at first, as M-T B says,
BUT material could be brought for a "short line"
railroad from "Jidda" to Salbyton!

Thus there could have been a rr station @ Salbyton,
with as many sidings as an Author could desire,
while the Main Line of the TTE was still stopped at
"Bab El Mandel" waiting for the straits to be bridged.

It was because the Traisum Cut would obviously take
so long, that it was important to begin it ASAP,
while the Salym-Bab El Mandel-Karys Line would be
allowed the same time (4 years) to be finished.
(Or perhaps even more time. It was not as if there
was some Major Enemy beyond the Karys Gate, so that
a railroad would be needed to fight him! :D )

Thus the Texts are shown not to conflict after all.

Howard True Map-addict

Mil-tech bard wrote:brnicholas,

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

The TTE Railways arrival at the Traisum Cut long after the Sharonan survey team is wiped out and avenged isn't implied.

It was both stated as fact by the Calirath Crown Prince Janiki and is a major plot point to push Voice Kinlafia to Sharona -- to be a politician and protector of Janiki's sister per Janiki's Glimpse -- before the attack on Ft Salby.


brnicholas wrote:The statement that the railway did not reach the cut until it was completed is either a misunderstanding of a text on our part or a continuity error on David and Linda's part. While their are a couple of texts which imply that the railroad didn't reach Fort Salby until after first contact with the Sharonans it is clearly established and a major plot point that all the sidings used to hold railroad cars and equipment while the cut was being dug and Fort Salby was the end of the rail line are still at Fort Salby!

From the prologue of Hell Hath No Fury, "the remaining buildings of Salbyton had a look of permanency and solidity which was rare this far from Sharona, and the local railroad station had quite literally miles of heavyduty sidings left from its days as the end of the TTE's line."

From Chapter 32 of Hell Hath No Fury, "Chan Geraith had seen the endless lines of work cars, portable machine shops, flatcars loaded with bulldozers and scrapers, passenger cars, portable sawmills, auxiliary steam engines, loads of unused rails and ties, bolts, spikes, hammers, pickaxes. . . . The list seemed endless, and the cars and work locomotives filled the extensive sidings left behind when TTE finished construction of the Traisum Cut almost to capacity."

Nicholas


Nothing in the passage above necessarily makes the Hell's Gate passage a "continuity error", as "completion of the RAILWAY" was not given a date.

Hell's Gate makes clear that the TTE railway had not reached Salbyton until months after the Andaran Scouts wiped out the Sharonan survey team, and the PAAF wiped out the Andaran Scouts in turn.

The heavy civil engineering of removing the rock in the Traisum Cut, to have a workable railway grade through the mountain, happened before the railway arrived.

That this is not the sequence I'd logically expect does not change the fact this sequence is tightly tied to a major plot point to get Voice Kinlafia to Sharona before the attack on Ft. Salby.
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Re: Relative size of combatants
Post by brnicholas   » Mon Jul 20, 2015 5:20 pm

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The first passage I quoted says the sidings were "left from its days as the end of the TTE's line." The second passage I quoted says explicitly that the sidings at Salbytown were "left behind when the TTE finished construction of the Traisum cut." I don't see any possible interpretation of those passages other then that the TTE was running standard gauge trains too Fort Salby while the Traisum cut was being dug.

I think the passage Mil Tech bard is thinking of means that work crews to build the railroad past Fort Salby didn't arrive at Fort Salby until after the battle of Fallen Timbers.

Nicholas
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Re: Relative size of combatants
Post by Howard T. Map-addict   » Mon Jul 20, 2015 5:38 pm

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Standard Gauge, yes, but did they come from Jidda,
or all the way from Bab El Mandal?
Why would TTE use any gauge other than Standard?
Why would they have engines and cars of other gauges,
so far out from home?

HTM

brnicholas wrote:The first passage I quoted says the sidings were "left from its days as the end of the TTE's line." The second passage I quoted says explicitly that the sidings at Salbytown were "left behind when the TTE finished construction of the Traisum cut." I don't see any possible interpretation of those passages other then that the TTE was running standard gauge trains to Fort Salby while the Traisum cut was being dug.

I think the passage Mil Tech bard is thinking of means that work crews to build the railroad past Fort Salby didn't arrive at Fort Salby until after the battle of Fallen Timbers.

Nicholas
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Re: Relative size of combatants
Post by Keith_w   » Mon Jul 20, 2015 6:43 pm

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Mil-tech bard wrote:brnicholas,

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

The TTE Railways arrival at the Traisum Cut long after the Sharonan survey team is wiped out and avenged isn't implied.

It was both stated as fact by the Calirath Crown Prince Janiki and is a major plot point to push Voice Kinlafia to Sharona -- to be a politician and protector of Janiki's sister per Janiki's Glimpse -- before the attack on Ft Salby.


brnicholas wrote:The statement that the railway did not reach the cut until it was completed is either a misunderstanding of a text on our part or a continuity error on David and Linda's part. While their are a couple of texts which imply that the railroad didn't reach Fort Salby until after first contact with the Sharonans it is clearly established and a major plot point that all the sidings used to hold railroad cars and equipment while the cut was being dug and Fort Salby was the end of the rail line are still at Fort Salby!

From the prologue of Hell Hath No Fury, "the remaining buildings of Salbyton had a look of permanency and solidity which was rare this far from Sharona, and the local railroad station had quite literally miles of heavyduty sidings left from its days as the end of the TTE's line."

From Chapter 32 of Hell Hath No Fury, "Chan Geraith had seen the endless lines of work cars, portable machine shops, flatcars loaded with bulldozers and scrapers, passenger cars, portable sawmills, auxiliary steam engines, loads of unused rails and ties, bolts, spikes, hammers, pickaxes. . . . The list seemed endless, and the cars and work locomotives filled the extensive sidings left behind when TTE finished construction of the Traisum Cut almost to capacity."

Nicholas


Nothing in the passage above necessarily makes the Hell's Gate passage a "continuity error", as "completion of the RAILWAY" was not given a date.

Hell's Gate makes clear that the TTE railway had not reached Salbyton until months after the Andaran Scouts wiped out the Sharonan survey team, and the PAAF wiped out the Andaran Scouts in turn.

The heavy civil engineering of removing the rock in the Traisum Cut, to have a workable railway grade through the mountain, happened before the railway arrived.

That this is not the sequence I'd logically expect does not change the fact this sequence is tightly tied to a major plot point to get Voice Kinlafia to Sharona before the attack on Ft. Salby.


I am pretty sure that it was less 2 months from the time that the Arcanans tried to wipe out the Sharonan diplomatic team until the battle at Fort Salby. Not much time to build a railroad the distance that Mil-Tech is suggesting.
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A common mistake people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.
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Re: Relative size of combatants
Post by Castenea   » Mon Jul 20, 2015 6:50 pm

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I think there would be a fairly large population in the Salby universe. How do you feed that large work crew building a bridge across the Bab-al-Mandeb, and the large work crew cutting a large chunk out of a mountain in the Hejaz mountains? The nearest areas suitable for conversion to high productivity farmland are Mesopotamia and the Nile delta. While there will be areas west and south of the incoming portal suitable for tropical agriculture, going north aside from the occasional oasis that would at best produce a limited surplus, the nearest area where you could grow crops without irrigation is the hills north west of the dead sea.

I suspect that once that bridge is completed there will be rail all the way around the Finger(red) sea.
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Re: Relative size of combatants
Post by Jonathan_S   » Mon Jul 20, 2015 9:59 pm

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Mil-tech bard wrote:Jonathan_S,

This:

[snip previous quotes on ropeways]

...is one of those places we are going to have to disagree.

The most important point here is the text says no railways were used in the construction of the cut.

The railway came after the cut was complete.

So if there are no railways, there was no way to deliver to the cut the huge TTE cranes, steam shovels and other equipment extended and articulated rail cars can deliver.

That leaves something else.

Now some of the links to photos and slides of the most likely something else -- ropeways and cable ways. The following are examples of both heavy construction and as transportation --

1. Ropeways in heavy duty civil engineering from the LCS Cable Cranes web site.

Material Ropeways

http://www.lcs-cablecranes.com/transpor ... l-ropeway/

The rotating photos at the link above shows the application of the technology to mountainous heavy duty civil engineering. The photo of the ropeway digging out of a mountain cut is spot on for Traisum applications.

This is the accompanying LCS promotional text --

Ropeways to enable construction sites

Our cable cranes show a clear advantage for all complex construction sites – where access for heavy machinery to deliver tons of construction material and construction equipment is almost impossible.

Difficult terrain that can be opened only with large time and financial expenses building access-roads, but could reached quickly and cost-effectively through the use of our systems.

Material ropeways do not only allow a quick and safe transportation of goods to the designated points, but permit a continuous operation schedule 24/7 on throughout the whole year.

Material cable-cranes are applicable in all sorts of geographical locations – high mountains, forest, over rivers, lakes or other landscapes, but as well in all kind of climatic conditions – from snowy mountains, to rainforests and dry deserts. They can be used for almost all kind of construction sites: mountain construction sites, pipeline construction, bridge construction and in forestry.

A material ropeway is ideal for operations where a safe, fast and above all efficient transportation of heavy loads is required.



2. From the "howtopedia" the Construction of Aerial Ropeways in Nepal


Construction of Aerial Ropeways - Nepal

See Figure 6 for a photo of a small Hydro-powered ropeway transport system with a guyed tower.

http://en.howtopedia.org/wiki/Construct ... ys_-_Nepal

3. A paper from the Nepal Ministry of Peace and Reconstruction.

Paper on Graduating Upwards from Suspension Bridges to Ropeways and Cable Cars:
Nepal's Experience and Expertise
by Bhim Updhyaya
23 Nov 2014

See the photos in slides 24 thru 32 of the presentation and in particular several examples of exceedingly long cableways without intermediate towers, guyed or otherwise.

http://www.slideshare.net/BhimUpadhyaya ... m-updhyaya


4. The Seti River Ropeway, 450 meter length, no intervening towers

Mechanized Bridge (River Crossing Passenger Ropeway)

http://www.gridnepal.org.np/project_det ... ion-c.html
And only a 25 meter height difference. A nice example of how a fairly horizontal segments can be quite long; though it's 450 meter length is less than half the height of the Karys side cliff; and more like 1/3rd the length of even a 45 degree ropeway down the face. But horizontal examples don't prove much about more vertical segments; because the mechanical stresses change significantly as you get close to vertical
Mil-tech bard; continued wrote:

It is a bicable bidirectional type of ropeway technology operates under motor power design and builds by the engineers of Nepal using locally available materials. The system is installed as prototype for human transportation connecting Kotre, Tanahun and Punditar, Kaski over Seti River having 520m with 25m level difference. At that section, numerous efforts of bridge construction was in vain due to technical infeasibility. So ropeway technology for river crossing is the best at such long span. The technology is also economical considering construction as well as operation cost for the span greater than 450 meters.

First, I already said that the TTE might well have had ropeways on the Traisum side to support construction. But there's not any pressing reason I can see for any construction ropeways to continue down the cliff face to the Karys side.

My sole objection had been about the technical feasibility of that one (very long and steep) segment (and as I said you finally explained it so I could see a feasible approach). But it's always been pretty clearly feasible to run a ropeway up the mountain slope on the Traisum side.


Your arguments have been a little harder for me to follow, either you're skipping around a little or else I'm failing to pick up on the clues for how your thoughts all tie together (partly because you're posting links to existing ropeways without explaining how you see those specific examples demonstrating how a ropeway meets the specific terrain challenges faced around the cut).

I see what seem to be 3 different ropeway arenas, each with different difficulty and benefits
1) Down the cliff face into Karys. This is the one I was getting hung up on.
2) Up the mountain slope in Traisum. Practical and quite possibly used.
3) Long overland ropeway to move heavy equipment from the sea to Fort Salby and the cut worksite. If you brought this up before this most recent post I must have missed it. But it's technically feasible to have built this;I'm just not sure they'd have needed the heavy equipment before the railhead reached the cut worksite.


I think construction ropeways, on the mountain slope, would have been especially likely if they'd attacked it in stages of no more than, say, 500 feet deep. That would avoid having to place charges up several thousand feet of cliff as you approached the Karys side. However to do that you'd have to move explosives and drill equipment well up the mountain slope; long before you pushed the 'ground level' cut that far into the mountain.
Actually if they just attacked it from the side it would have been easier to make most of it a tunnel, rather than clearing all the thousands of feet of rock above that point; so I have to imagine they'd have attacked it in stages; more or less top down.
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