The age of urban warfare is already here. It cannot be avoided any longer. And the urban environment includes not just what is on the surface, but also super-surface and subsurface levels. Most major urban areas include an entire world of underground transportation, maintenance, water, sewer, and telecommunications tunnels. Tunnel warfare has gone hand in hand with urban warfare from the time when medieval warriors attacked castles. Since then, tunnels have been used by urban insurgents, revolutionaries, and terrorists, such as Chechen rebels during the two battles of Grozny to the even more recent extensive use of underground terrain by ISIS across Iraq and Syria.
Knowing how to shoot, move, communicate, survive, and adapt in subterranean environments is as foreign to most soldiers as walking on the moon. Much of the technology I have seen being developed for operating in this environment focuses on breaching, communicating, and navigating. There are also efforts to develop robots to advance into tunnels for a variety of tasks and situations. All these are very important. But when the time comes to send troops underground, here are a few things I would have wanted in my kit bag, some at the cutting edge of technological advancement, others substantially less so.
1. A new way of thinking about the underground domain. The Army thinks about subterranean environments too narrowly. As a career infantry officer, I did, as well. Too often we think of the subterranean as an obstacle to be negotiated if encountered. We train primarily on entering and clearing tunnels—a reflection of our similar over-emphasis on entering and clearing a room to prepare for the full spectrum of urban operations. The vast underground world of most major urban areas should be treated as a separate environment and capabilities developed not just to deal with it, but rather to dominate it. The US military once had an advantage over our enemies in night operations; we “owned the night.” We can achieve a similar dominance in the subterranean with a different way of thinking about it. The military should think about the implications, advantages, and disadvantages of conducting the full range of military operations (especially offense and defense) underground. For instance, if the Army’s new warfighting concept calls for the Army to “pose multiple and compounding dilemmas on the adversary,” why wouldn’t the service make major investments to circumvent enemy urban defensives, such as those seen during the 2016–2017 Battle of Mosul, by either using existing underground networks, or creating new ones.
2. Underground goggles. Thermal goggles or any other non–light dependent goggles would equip soldiers to see through the dark. Normal night-vision goggles require ambient light. The Army has fielded new thermal-equipped goggles, but it may take a while to get them to all soldiers or perfect them for subterranean operations.
3. Blinding light source. Not only do I want the ability to see while underground in a tunnel, but I also want the ability to take away visibility from others. A big, blinding light (it shouldn’t be too small or all the enemy has to do is shoot at the light) with a dependable, long-lasting power source would give soldiers a marked advantage over anyone laying in wait.
4. Sound nonlethals. Sound travels differently underground. The environment may be ideal for employing incapacitating sounds against an enemy.
5. Ground-penetrating radar. These devices are widely used in many different fields, from archeology to construction to mining. I would want a handheld device to see through the walls of tunnels (in all directions—laterally and vertically), and to know my distance from the surface.
6. Bat vision. Bats use echolocation to navigate, projecting sound waves against surfaces to “see” and fly. On top of ground-penetrating radar, I would like to see how existing sonic technology could be used, for example, to show what is to the front of a patrol maneuvering through tunnels.
7. “Guardian dog.” Similar to the “guardian angel” concept of having a loitering UAV overhead to provide situational awareness and in some cases supporting fire, I would want a robot above ground that is offset of the moving element. When called electronically, it would move to the patrol location and drop a winch, supplies, or whatever else is needed.
8. Infrared reflective ropes and cords. When FDNY firefighters go down into tunnels, they use a guide rope (either tethering themselves to one another or laid down and kept between their feet) to make sure they know where their teammates are even when they are spread out. It would help a patrol to stay together, know where they have been, and how to get back. US forces exploring caves in Afghanistan tethered robots with rope to prevent losing them. There are many uses for cord in tunnels, but an infrared rope or cord would be even better so that only soldiers could see it. A nice interim fix would be a solution that adds IR reflective properties to the ever-present and dependable 550 cord.
9. Robot rat. A tunneling robot could be used to make a new path underground. There are plenty of situations that may arise where following an existing tunnel may not make sense. Why not have a way to create a different path to the objective or create a bombproof shelter? In the age of electronic warfare, where it is nearly impossible to hide military forces, quickly going underground offers a solution. Inventor and entrepreneur Elon Musk has undertaken a major investment in increasing the speed of boring machines. A faster, lighter, less expensive boring machine could be a significant part of future warfighting concepts and of value to warfighters.
10. Foam grenades. I want the ability to seal different branches of tunnels as I pass them. A quick-forming industrial foam might do the job. What are the current options for soldiers underground who encounter opposition? They can’t pop smoke and can’t dive to cover. Could foam be used to create an immediate wall so that soldiers would have time to egress?
11. Dogs. Military working dogs are still a powerful tool even in underground tunnels. Currently such specially trained dogs are mainly used by special operations forces, military police, and a few other units. The capability and skill to use them should be provide to more forces.
12. An upgraded shovel. The famed entrenching tool that is well known to any soldier that has served for generations has changed little in its history. If any thought is given to soldiers operating underground, then a new lighter, stronger shovel is needed.
13. Lights, lights, and more lights. It is shocking that even into the 2000s, the US military continued to use the Vietnam-era L-shaped You can still find them required for military schools and sold at on-post clothing and sales. Soldiers often now buy and carry their own civilian headlamps, and SureFire flashlights were populated across the force to place on weapons, but where is the military-grade, lightweight flashlight for underground operations? What is the solution to establishing a patrol base or headquarters inside a cave or tunnel? Current long-lasting lighting solutions are powered by generators, which are clearly not feasible in the confined spaces and with the vulnerable air supplies found underground. Any lighting solution will have to also address other issues related to power sources, to include the weight of batteries. Solar power certainly isn’t an option, but successfully operating underground will require finding one.
14. A canary. There are major issues with oxygen levels, carbon monoxide, and many other air concerns when going underground. I know there are plenty of advanced air-monitoring devices out there, but even if I had one (like the NBC indicators we had to carry when I was a soldier), I wouldn’t totally trust them. Miners have carried canaries underground for a long, long time. If the bird goes down, you have a problem and need to act.
This is far from an all-inclusive list of the types of items needed for underground warfare. But it may provide a few ideas for the Army, if and when it begins to make necessary changes in the way it thinks about and plans for the subsurface levels of urban areas in future conflict.
Image credit: Sgt. Jessica DuVernay, US Army
The Guardian dog; by virtue of being a very easy target (because it's on the ground and does not have the Guardian angel's inherent protection of being quite high off the floor), presumably I'll need to put some people around it to protect it. At which point, why have the dog? Those people have to be there, so they can do the winching and supplying, can they not?
You might want to get something to read like, The Tunnels of Cu Chi.
A canary? Seriously? That comment alone made me disregard the entire article. If you really don't think electronic monitors would do the job better than a small bird you need to stop advertising yourself as an Urban War SME. Spend some time hanging around Mine Safety Appliances (MSA) and check out their suite of safety equipment that does exactly what you describe – they've been experts at this stuff for a century.
Also glaring was the lack of a robot with the ability to recon and attack enemy with onboard weapons. Why would you ever send an infantryman into a dangerous tunnel situation without exploring it completely with a UAV or robot first? Tech has advanced so far so fast that suitable robots either exist already or will in the next few years yet you don't see the need?
By the way, NVG's don't require 'ambient light' to function. They can work well in total darkness (zero illum) if you provide some energy on the IR spectrum – what aviators would call a 'pink light'.
I generally agree with the list, but there are a few add-ons I would like to see:
1. A new way of thinking about the underground domain. FMs/TCs/GTAs/etc. that illustrate the different types of subterranean systems. Most soldiers tend to think that every city has a sewer system that works like an episode of Teenage Mutant Ninja Turtles, but that has never been the case. Most are more suitable for trained rats and drones (if we can develop suitable means of subterranean signal) than for a human being, let alone a fire team. I don’t believe there are any cities being built with a combined sewage system, anymore, and the idea of infiltration through sewer tunnels is becoming less feasible. On the other hand, subway tunnels are becoming more readily available, especially as cities in less-than-stable countries vie for the lucrative honor of hosting major sporting venues. The dangers of black water aren’t the same as those of a third rail or speeding metro, but all are a consideration to which the average tactical soldier is largely ignorant.
9. Robot rat. I would add tools such as halligans, subterranean-specific demolitions, and even thermal lances to enhance tunneling operations. Not everything needs to be tech-heavy, and we should train and understand the dangers of using such tools in an underground training environment before we ever have to apply them.
11. Dogs. And rats. And pigeons. Et al. I love dogs, but as sewer systems grow smaller, it makes sense to expand our use of other animals with proven military value.
14. A canary. This is the one case where I will argue for high-tech over low-. Canaries are cheap, but they require manpower to feed/clean/monitor. They also don’t tell you when they die. Artificial sensors can give off warning signals at stages intermediate to alive or dead, and don’t require someone watching them instead of their sector. By all means, have redundancies in place, but this is one area that should be modernized.
Key areas are logistic, C3I, especially situation awareness of surface and underground.
Use a powered datacable as your comms cord. Plug wifi repeaters into it, and splice as needed. Use remote, IR-Visual- wide spectrum sound- sensors communicating to wireless repeaters to create awareness without multiplying the force protection. Reinforce with remote weapon stations, with ROE control from CP.
Use datalink to maintain situation awareness with above ground situation- enabling popup attacks and movement. Noise travels well underground. Use networked wide spectrum (audible and sub-audible) sensors to DF movement above and below ground.
Treat environment as a NBC environment. Wear appropriate PPE for risks, carry sensors for chemical risk (CS, CO, Low O2, Methane) and react with appropriate drills. Dead air is an asset for area denial. Use Expanding Foam to create temporary walls, deny area beyond wall with CO/CS. Cover dead area with remote Weapon station and sensors.
Additional logistics requirements will include pumping fresh air into occupied spaces and extracting stale air. That creates need for defended or concealed access to surface. Comms systems designed for open plains will fail- use VOIP over datanet.
CASEVAC may be limited to one or two suitable exits, and these become key ground.
If fighting an underground force- extract all assets- close all water egress points- then flood underground space with CS/CO/Water.
Literally, rinse- and repeat as needed.
I love this article and the idea that this is being thought about. Some thoughts to expand–not criticize the idea.
4. Acoustic weapons already exist in the form of PSYOP loudspeaker systems, LRADs, etc. The greater concern is hearing protection. Underground, acoustic weapons work both ways, and will echo far through a structure rather than dispersing in the open air, so there's a risk of acoustic fratricide. In this regard, the acoustics of weapons fire will need to be addressed as well. Regular hearing protection will be insufficient. Sound dampening protection with active cancellation would be a good investment.
4.a. Unmentioned in the article, a similar issue exists with using explosives with the shockwaves propagating rather than dispersing. The guys at the Fort Hood underground facility showed us a door warped by the pressure wave of C4 set off on the other side of the facility. Tunnels canalize shockwaves.
10. Love the idea of foam grenades, that's thinking outside the box. But also consider the volatile organics put off by current industrial foams and their impact on air quality in a tunnel system. Foam systems with less impact on the air quality (I don't think we could get to zero effect) would need to be looked at.
14. Absolutely, though the alternative might be manpack oxygen supplies like the Navy has on its submarines. One huge issue with firefights underground–besides the acoustics is the firing of weapons consumes oxygen in addition to fouling the air. It might make more sense to carry oxygen supplies rather than trying to react to the loss of oxygen.
As an S&T oriented person, the challenge with this article is it follows a common problem: specifying the solution. As an example: bat vision, using echolocation to provide a measure of SA in a visually degraded environment. The problem is a low to zero light environments, possibly degraded with aerosols and fine particulates, which limits visibility. Rather than specify the solution, describe the problem and attributes that the ideal solution would have. My first approach at a solution would be a scanning ladar which would provide a 3-d view of the environment with nearly zero computation required, and could be done in non visual wavelengths. The foam grenade is a solution to blocking entry points or possibly providing cover, in short, some sort of temporary barrier that is adaptive to many shapes and sizes of openings, may need to be easily reversible, and deploy easily and quickly.
Present people with the challenge and attributes of the solution, and folks will find creative ways to solve it.
Underground environments present unique challenges and these need to be acknowledged and addressed.
I wonder if the Army knows that the answers could be solved via television and film.
Tunnel Warfare’s Wish List reminds me of the Sci-Fi movies back then of the future…”ALIENS” for example. Sentry guns, trackers, flame units, grenades with high-yield explosives, armor, pump-action grenade launchers, 95-round magazines, Smart Guns, handheld welders, shoulder lights, helmet cameras, biometric sensors, wristwatch locators, pocket tools, shoulder, thigh, and shin armor, motion detectors, syringe medicine, etc. were all utilized for confined space warfare on a planetary base, better known as “Tunnel Warfare” according to the base’s architecture.
This technology is all readily available now. “ALIENS” movie was made in 1986…
Problem with sound non-lethals would be that as soon as it's revealed to the enemy, it becomes pretty ineffective. It's easy to counter as soon as you have information about it. You would need some sort of special sound to affect inner ear through protection then but that sounds more like sci-fi at this point.