»IN A LETHAL-FORCE ENCOUNTER, especially at close range, the longer you allow the threat to continue to attack, the more likely you’ll be killed or seriously wounded.

Even if you manage to deliver a lethal shot, if it fails to incapacitate your attacker before he wounds you, your chances of survival are slim. That’s why self-defense focuses on stopping power, not killing power.

Although that logic seems painfully obvious and is accepted in gun-based self-defense, it often gets derailed when it’s translated to other weapons, particularly knives. And if you’re going to carry a knife as a defensive weapon, your first priority should be to have a clear understanding of how it stops threats most effectively.

Bullets “stop” by destroying the central nervous system (brain and spinal cord) or by causing trauma and blood loss to the heart, lungs, viscera or major blood vessels. Since the comparatively low velocity of most handgun bullets does not produce hydrostatic shock, multiple — sometimes numerous — shots to the torso might be required to stop the threat. If we put this into the context of a contact-distance threat, like an attacker trying to bash your head in with a tire iron, you would stop the action of his weapon arm (the true lethal threat) by shooting him in the head or torso to shut down his entire body.

High school biology teaches us that veins return blood to the heart and have low blood pressure, while arteries have higher pressure and bleed more profusely.

If, however, you are armed with a knife, things change dramatically. First of all, you would have to defend from contact distance, which means you remain in close range of the attacker’s weapon until you stop the threat. Assuming you’re using a small knife that’s actually legal and practical to carry, its destructive capacity would be limited. Thrusts to the torso would be even less effective than gunshot wounds and would take longer to achieve stopping effect. If you control the attacking arm with your non-weapon hand, you could stab him repeatedly until he drops, but you’d be in for a long, bloody rodeo that does not guarantee your safety.

Another possibility would be to avoid or control the attacking arm and stab or cut the attacker’s neck to “bleed him out.” This approach, immortalized in the cliché “going for the jugular,” is even less effective and one of the most pervasive myths of knife tactics. High school biology teaches us that veins return blood to the heart and have low blood pressure, while arteries have higher pressure and bleed more profusely. The actual target in the neck would therefore be the carotid arteries on each side — where you take your pulse. Unfortunately, despite common belief, even they aren’t effective stoppers. This is where the real myth-busting comes in.

The most efficient way to stop an attacker with a knife is to destroy the specific body parts that make him dangerous to you.

In 1942, close-combat pioneer W.E. Fairbairn — co-designer of the famed Fairbairn-Sykes Commando Dagger — wrote the classic book Get Tough, which included his highly controversial “Timetable of Death.” This table identified the major blood vessels of the body and listed, in specific detail, exactly how many seconds it supposedly takes for a person to bleed to unconsciousness and bleed to death when those vessels are severed. Long considered gospel, this classic bit of close-combat history was not only completely unsubstantiated, it was also wildly inaccurate.

According to Fairbairn, a severed carotid artery would cause unconsciousness in five seconds and death in 12. In reality, the time it takes for a person to lose 30 percent of his total blood volume — the threshold for unconsciousness — is directly affected by his heart rate. But even at a maximum human heart rate of 220 beats per minute, it would take approximately 68 seconds to bleed to unconsciousness with a severed carotid, not five.1 Sixty-eight seconds at arm’s length with lethal weapons is an eternity. As such, people simply don’t bleed fast enough for blood loss to qualify as an effective stopping tactic.

Instead of targeting the entire body, the most efficient way to stop an attacker with a knife is to destroy the specific body parts that make him dangerous to you — starting with the grip on his weapon. In simple terms, movement of the human body involves nerves, muscles, tendons and bones.

Our tire-iron-wielding attacker is able to grip his weapon because his brain sends messages through the nerves of his arm to the muscles of his forearm. When the muscles contract, they pull on one end of the flexor tendons on the inside of his wrist. The other end of those tendons is connected to his fingers, which, in turn, close to grip the weapon. Cutting the muscles of the inner forearm or the tendons of the wrist disconnects the mechanical elements of that process, instantly crippling the hand and forcing it to open.

Any time an attacker swings a weapon at you, he literally “gives” you targets by extending his arm toward you.

Since the nerves that control the hand are bundled with the muscles and tendons, deep cuts stand a good chance of severing them as well. Unlike trying to stab deep into the torso to reach vital organs, the tissues of the forearm and wrist are quite shallow and very easy to cut to the bone, even with a small knife. Best of all, any time an attacker swings a weapon at you, he literally “gives” you all these targets by extending his arm toward you.

Although this tactic is found in many edged-weapon systems, it is best known as “defanging the snake” in the Filipino Martial Arts (FMA). In FMA culture, the weapon is the fang and the arm is the snake. Removing the fangs from the snake immediately destroys or severely compromises its ability to kill and instantly makes you safer. Although battlefield FMA tactics would then follow up with additional cuts and thrusts to lethal targets, a better, self-defense-oriented approach would be to apply the same principle of structural and neurological targeting to other key body parts, further disabling the attacker as the situation warrants. We’ll delve into this deeper in future articles.

“Stopping power” is the ultimate goal of all self-defense. Achieving it reliably and predictably with a knife requires a sound understanding of human anatomy, good tactics and an open mind.

ENDNOTE

(1) Grosz, Christopher and Janich, Michael D., Contemporary Knife Targeting. Paladin Press, 2006.