Glass-breaking is a function about which I keep hearing but don’t fully understand outside a military situation. I assume it refers to evacuating a car after an accident or other emergency. My problem with this is that almost nobody wears their survival knife on the way to and from work. If the knife is in the trunk with your BOB, how is it going to help? In a military scenario, I can see rescuing aircrew from a downed chopper; however, that situation is very different from what we’re likely to face. In the military, you have your gear on your person so your knife will be handy. Aircraft canopies are made of a plexiglass material, so I doubt it breaks like glass anyway. Egress from an automobile in an emergency would need to be executed with whatever is anchored within reach of the driver, which probably means something fixed to the dashboard or in a console compartment. Given the limited room involved, the tool will not likely be a survival knife. More likely, a folding blade knife with a “glass-break” tip on the handle or similar tool will be used. Therefore, I see this as a survival function but not the function of a survival knife, if you can see the difference.
Defending yourself with a knife is a subject well beyond this article. A couple of points for new folks: First, you must understand that in a fight, the guy who has trained and practiced will beat the guy who hasn’t, period. The weapoon is immaterial. If you have never had any training in this area, you might want to get some. If you have had some training, then you already know the general parameters of the weapon on which you trained. Use that weapon. Familiarity and muscle memory will beat new and cool every time. Will a kukhri beat a Bowie? That’s the wrong question! Which guy knows what he’s doing better? So, either find a knife you like and get trained on that weapon or get some general training and then get a weapon which fits your training. Back in the day, bigger was better. That’s not so today, based on your training.
The subject of defense would not be complete without discussing the improvised spear. What I refer to here is lashing or otherwise affixing your knife to a sapling pole to create an ad-hoc spear. Since no one I know practices spear techniques for defense against people, I will defer to our previous discussion. The practical side of this I can see would be defense against animals. Wild hogs are thick and ugly where I live. If I had to face a hog without a firearm, a spear would be my next choice. I can see a similar issue in areas with big cats or wolves. My concern with the concept is the actual lashing. Many knives have touted their abilities as spears. Most have holes at various points to enable lashing to a pole. The problem is that most people cannot tie the knife securely enough to a pole to prevent loss of the knife once you jab the animal in question. Once you lose your knife, all you have is an unsharpened stick. This leaves you in something less than an enviable position. I have not made this issue one of the decision criteria for my carry knife. If, in your evaluation of your situation, you see the spear concept as necessary, then select a knife with multiple attachment points and have the proper cord available. Then practice it and check how secure the knife is. Practice some more, and check again. Or maybe just go with a sharpened stick and keep your knife on your belt.
Skinning and processing wild game is an important skill you need to practice. Large animals, like elk and moose, lend themselves to the use of a large knife. Small game, like rabbits and squirrels, though need a small- to medium-sized blade. Conflicting requirements? Yes, but there is a solution.
- In your retreat you should have knives of several sizes, so that you can have the right knife for the job, whether it’s large or small. Regardless of size, all these knives should be razor sharp.
- Your experience hunting will guide your choice of knives. Where I live, whitetail deer are the biggest game animal I will typically have to skin and process. Many friends carry a 4” Pendleton-style  hunting knife while deer hunting. Too small? It works for them. The more important question is whether your big survival knife will do the job? There is a great deal of room in this function for different blade shapes and lengths. If you don’t hunt now, you really should start. It will allow you to practice many skills you will need later. If you do hunt, do you carry your survival knife? Why not? If you cannot use your survival knife for skinning and processing game, you probably ought to reconsider your choice, in my humble opinion. Of course the issue of only one knife arises here again. Even when hunting, I carry several knives because each does a particular job well. There are several quality folding knives that could help, particularly if your choice of survival knife does not lend itself to skinning or gutting.
General cutting chores around camp include such actions as cutting string and cord, meal preparation (outside of processing game), cutting material for repairs, cutting bandages, slicing bread, spreading peanut butter, and just about anything else you do with a knife that has not been covered elsewhere. Most of these chores can be accomplished with any size of knife, as long as it is sharp. So while your knife will do a lot of work in this category, it is probably not one upon which to base your decision. I recommend going camping for the weekend to see all the things you do with a knife; then evaluate your potential choices in light of this. If you already have a survival knife, how often did you choose to use something else for cutting? Why? What did you do that was better done with a longer blade? What did you do that was better done with a shorter or thinner blade? How can you resolve these issues in your situation?
Somewhere between the last two categories comes preparing fish. Most folks immediately jump to the classic filet knife with its long, thin, flexible blade. While excellent for fileting fish, this type of knife is generally not very useful in many other functions. Don’t worry; many other knife blade styles will work adequately. The Scandinavian Mora-style  blades are traditionally only about 4” long and stiff rather than flexible, yet their fishermen have used them for centuries. I fileted a crappy once with a Ka-Bar. It’s not pretty but functional. Unless you anticipate eating fish almost exclusively, this is probably not a decision criterion for new folks.
Chopping, hacking, and splitting are all different functions that often get lumped together. We will define chopping here to be the cutting in the classic “V” shape and requiring multiple strokes of the blade. Chopping of vegetables for food preparation or small branches with one stroke is not what we are talking about. When on the trail away from your retreat or in a more everyday survival situation, chopping is not an activity you should do a lot. It simply expends too much energy. Sawing is a much better answer. Generically, chopping requires a heavy head, like an axe. No knife blade is really a good axe, although a kukhri  is a very functional chopper. This is the category where blades other than knives come into use. Blades such as machetes, hatchets, tomahawks, and shingle hatchets make much better choppers than virtually any knife. Even the largest Bowie-style Rambo knife just does not have enough weight or leverage behind the cutting blade for efficient chopping. That being said, the size of the material you are chopping really determines the blade you need to chop it. What are your likely situations? I have used a kukhri, a machete, and a shingle hatchet for chopping duties while camping over the years. I still own them all, but I don’t carry them hiking. The machete  is in my truck, because I use it all the time while the others are at home. In the areas I go, I don’t anticipate a major chopping requirement. If you do, you should consider a tomahawk, machete, or kukhri.
Splitting typically requires a heavy, wide blade. Splitting firewood on the trail is typically not an issue, since if you have a fire it should be small. Small pieces of wood can be split effectively with a Ka-Bar or similar knife if you feel the need. I have used my machete for splitting wood for various projects but obviously not on big logs. Splitting cattails, yucca shoots, and the like for food, materials, and such can be accomplished with pretty much any knife. Typically, whatever you use to chop, you will use to split.
Hacking, as used here, is the function of clearing brush, vines, branches, and other plant growth from trails, campsites, shooting lanes, and such. Since you are typically not chopping big timber, this is the province of the machete, brush knife, or kukhri. Axes are too heavy to be functional here. Tomahawks might work. I don’t have one, but they look light enough. At your retreat, have the right tool. A machete works, but so does a ditch axe and brush hook. On the trail, only the machete is light enough to make sense. Still, your camping experience here will help you decide if you need it in your situation. In a survival situation, a large camp area is not necessary and often undesirable. You need to eliminate unnecessary expenditure of energy. I have never cleared a campsite; I found a site that was clear enough. Even in the thick woods in my Southern mountains, I’ve never needed a machete to clear a path. I just found a clear path. What will work for your situation?
So what do you, as someone new to survival and prepping, need? I cannot say definitively what your answer will be, because I do not know your situation. Let me offer this guidance: Get some experience hunting, hiking, or camping. I recommend these activities because you will get out into nature and be around people who have used knives for many years. There are camping and hiking clubs in most areas. These folks may not be knife experts, but they are a good source of practical information. Most hunters today understand that expanding the hunter population is the only way the sport can survive, so many are open minded about teaching someone new. Ask around. Someone you know probably hunts and can help you with the details. You will likely get a lot of conflicting guidance. That’s okay. Everyone has their own perspective and priorities. Always ask why, when getting opinions; it can be very illuminating.
Instead of trying to find one knife that can do everything, many people group similar tasks and find a blade optimized for those tasks. For example, chopping, hacking, and splitting can be accomplished by a machete, a kukhri, or a tomahawk. While lousy at fine cutting tasks, any of those tools are far superior than a small to medium blade at chopping, hacking, or splitting.
Please do not rush out and get an expensive custom-made knife right off the bat. It may be a great knife, but it may not be the right knife for you. Experience will tell you what you need. Until you get that experience, I recommend buying a quality knife at a reasonable price. I recommend your top end be the Ka-Bar . It is an excellent quality knife currently priced between $103 and $123 on their website. There are many good knives on the market, priced between $50 and $100 from reputable manufacturers, like Gerber, Ontario, Cold Steel, SOG, and Kershaw. If you have to talk to a salesman, just use the term “belt knife” or “camp knife”. Look for a knife with a full tang, meaning the blade steel goes all the way to the end of the handle. Your first blade should probably be medium size, 5–7” long. The sheath, regardless of the material, should hold the blade securely, without allowing any of the blade to slip out.
As a matter of perspective, let me offer what I carry, in case it’s of use to you. Every day, I carry a Wenger Swiss Army Knife  and an A.G. Russell lockback folder. I carry these two knives 24/7/365, whether in jeans or a business suit. The Russell is an excellent knife with a solid steel handle and excellent steel blade. Its edge is literally a razor. The Wenger is my all-purpose tool. I use it for everything, and I have for decades. Together they give me the sharp cutting blade with near fixed blade strength and the functionality of the saw, screwdrivers, scissors, and file of the Wenger. When hiking, camping, and exploring the wilderness, I add a Puma brand Bowie-style  belt knife. It has a hollow ground 7” blade that holds an edge better than most knives I have owned. It came with an excellent heavy leather scabbard with multiple lash points in case I want it on my web gear or rucksack. Occasionally, I carry my old aircrew survival knife , more for old time’s sake than necessity. It’s still sharp as a razor and tough as ever.
I would love to tell you exactly which knife you should carry, but that would be foolish. You may get lucky and buy the perfect knife for you the first time out. I hope you do, but I would not bet on it. Experience is your best teacher. Good luck.