Underground

[Samuel]

Is there anyway that underground fighting could occur- not in facilities, but with tunneler units? Or is such an idea impossible?

[Eleventh Century Remnant]

If you look to the past for a reference, yes, tunnel fighting has happened in real life- in conditions of static warfare. Castle sieges in the pre and early gunpower era, mining and counter mining on the western front of WWI.

Digging under castle walls to undermine their foundations, counter-digging to collapse enemy assault tunnels, emplacement of mines, blowing up enemy mining tunnels- there has been underground warfare.
The 'tunneler units' were men with picks and spades, at times it might take a year to dig a mile, and the conditions may have killed as many of them as the enemy, but it happened.

I think the key phrase here is static warfare. It may be one of a horde of solutions that are having resources thrown at them, it may be the only solution to the military problem, but something as slow and therefore war-prolonging, indecisive and expensive as trying to chew through solid rock to get at your enemies is never going to be the first solution to the problem.

Most real world military tunneling occurred in heavy soils or clay, at most, but I assume this is in OSF for a reason, and there should be machinery- IIRC the chunnel dig went at about ~10 yards a day. If you want to set this up as a scenario for a game or a story, I'd say the first thing is to work out why all the normally decisive tools and tricks have failed or just aren't available

[JointStrikeFighter]

There was a concept posted in the HAB a while back for a nuclear powered melta-mole type vehicle, IIRC it could drill at a not inconsiderable rate as well as forming its own tunnel liner out of molten rock.

[Samuel]

What keep the thing from cooking to death?

[Sea Skimmer]

WW1 isn’t even the most recent example of tunnel fighting, though it is the most extensive. US tunnel rats in Vietnam used handguns and knifes in hundreds of missions into VC tunnel complexes, and when US and ROK troops explored the first North Korean invasion tunnel found in 1974 a landmine killed several of them. In Lebanon in the 1980s, the Isreals used specially trained dogs to carry explosives into terrorist tunnels as well (officially they no longer do this, the dog unit is for searching only, but who knows), and the US used robots to explore various tunnels in Afganinstan but with no reports of armed combat. No armed robots were available at the time unfortunately, but I’m sure troops would have wired up some demolition charges for the purpose had it been required. While no fighting has occurred within the tunnels, the Palestinians have also used tunnels to attack Israeli outposts on several occasions, exiting within or right beside them.

In general it’s these scenarios you’d expect the possibility of tunnel fighting in, either highly static warfare, or insurgencies, or a combination of both.

As for the nuclear powered tunnel melter, here’s what was posted in the original HAB thread.
http://www.fas.org/sgp/othergov/doe/lan ... 387371.pdf
http://www.fas.org/sgp/othergov/doe/lan ... 368561.pdf
http://ntrs.nasa.gov/archive/nasa/casi. ... 007687.pdf



Theirs a video floating around on Youtube as well showing a bunch of different Soviet AFV prototypes and projects. One of them was a tracked vehicle which would tunnel underground via conventional boring machines, but all they have is a basic CGI animation of it. I have no idea what the speaker actually says since I don’t speak Russian.

[Samuel]

Thank you. Who the heck came up for such a machine? I was thinking Perimeter style war vehicles, but that...

I want one.

[Cykeisme]

Well, since we're talking about sci-fi, the most common rationalization for ground conflict (in the face of interstellar warships with the giga- or teraton/sec level power generation) can be used to rationalize subterranean combat: energy shields.

If Star Wars theatre shielding and 40k void shields and continent-scale disruption fields can prevent bombardment from the air or the ground, presumably an appropriate combination of fictional shields, defensive firepower and planetary geography might force a besieger to tunnel in order to capture or destroy an enemy-held objective.

As for the methods and tactics involved in the actual combat engagements, extrapolation from real-life would be best, as has already been outlined here by more knowledgeable individuals.

[Samuel]

As for the methods and tactics involved in the actual combat engagements, extrapolation from real-life would be best, as has already been outlined here by more knowledgeable individuals.

"looks at cykeisme's sig"

It will follow past trends is... a little vague. Anyone have any idea exactly how it would work? Or is this like space where the loadout is incredibly important for how tactics evolve?

[Teleros]

Well I did have a nice long post but it got eaten, so...

1. Stealth versus speed is a big issue here. The faster you go, the noisier you presumably are (or more neutrinos you give off or whatever).

2. However, suicidal or desperate attacks may be easier when you've access to lots of obscenely powerful weapons: if you can park a suitably powerful laser or somesuch and simply blast through the intervening rock in a matter of minutes, you might be able to get inside quickly. Just pray the roof doesn't cave in, the other guys don't blow it the same way, etc etc etc. Rather a big "if", but there we go .

3. That said, how common are such underground assaults? Does the enemy fortress have shields extending into the bedrock? Do they have sensors designed to pick up sapping teams? If not, will they work out what it is their other sensors might accidentally pick up before it's too late?

[Sea Skimmer]

What’s incredibly important is just what kind of underground combat it is. The examples we’ve had so far basically fall into three categories, sapping, exploring/seizing major enemy underground works, and bypassing obstacles. Each of these would lead to different forms of fighting, and only entering enemy works is likely to lead to regular combat as opposed to just blowing up each other with camouflets.

[JGregory32]

1. Stealth versus speed is a big issue here. The faster you go, the noisier you presumably are (or more neutrinos you give off or whatever).

2. However, suicidal or desperate attacks may be easier when you've access to lots of obscenely powerful weapons: if you can park a suitably powerful laser or somesuch and simply blast through the intervening rock in a matter of minutes, you might be able to get inside quickly. Just pray the roof doesn't cave in, the other guys don't blow it the same way, etc etc etc. Rather a big "if", but there we go .

3. That said, how common are such underground assaults? Does the enemy fortress have shields extending into the bedrock? Do they have sensors designed to pick up sapping teams? If not, will they work out what it is their other sensors might accidentally pick up before it's too late?

Terrain is also a big factor. What kind of material your digging through can determine what means you use. Sand and granite are probably the worst kinds of material to try and tunnel through, sand becasue of the massive amounts of support you need to install and granite because of its hardness. Also in a seige situation you want to be as quiet as possible because the enemy is going to be listening for tunneling and rock is a great medium for soundwaves to travel through.
That said some kind of autonomous digging machine that bores out its own tunnel and collapeses it behind it's self and is armed with an nuclear charge is the stuff of nightmares.