This is discussion archived from a time before the current discussion method was installed.
Looney Toons: Excised from the text when I moved the pages around:
Transferred from Flak Jacket Discussion:
Oddly enough, the standard soft police vest can't stop knives or other stabbing weapons. This lead to problems in the UK, where knife violence outpaces gun violence significantly. Knife protection can be added to existing body armor by the addition of titanium chain mail, a dense layer of ballistic fiber or a solid plate of armor, like ballistic steel or ceramic. The hard armor option can also improve resistance to rifle fire, so it seems like the most logical choice.
I haven't seen any criminals on US television exploit the stab vulnerability of police vests myself. Has anyone else?
Not I. I am given to understand that US television and film production houses tend to have very close relationships with police departments, who provide them with technical expertise, crowd and traffic control, etc., and are reluctant to damage these relationships by making public the weaknesses of body armor, as this might anger the police. I guess they assume that crooks may not read very much, but EVERYBODY watches TV.
___ There's a slight misconception on the body text. Level II Ia vests *can* stop a large number of knives on the first stab thanks to being much thicker. Only a near stiletto thickness knife (and very sharp at that) can go through because it focuses the strike on a smaller area. Thicker or duller knives will take repeated stabbing to get through.
Bayoneted rifles and a large number of other weapons will go right through a Spike III insert on the first stab however.
Comments on the Lord Of The Rings example, and others, by Jove Hack.
The shirt shown in the movie of the Lord Of The Rings would have been no protection at all against a spear thrust. The spearpoint alone would have done enough damage to kill Frodo, since the shirt was flexible. Add in the crushing effect of the spear pushing Frodo and he might as well have been in a vice. There's a reason real world armor was stiff, heavy, and over heavy padding (See: gambeson). Thin, light, and flexible armor is useless against anything but minor scrapes.
The mass of armor is almost as important as its protection, since it provides inertia to slow down a blow. This is brought out in E.E. "Doc" Smith's Skylark Three. The Big Bad DuQuesne points out that in suit of arenak armor Seaton would be safe from anything but an artillery shell. (Think of an egg rattled around inside a covered cooking pot.) DuQuesne then speculates that Seaton probably had himself anchored with a tractor beam to protect against that.
Larry Niven gets that wrong in, I think, The Ringworld Engineers. Niven's fullbody suit of armor is fully flexible except under stress. So his hero pulls the hood over his face and jumps down three stories to land face down on the pavement with nothing more than a nosebleed. (There's a reason stuntmen always land on their backs after a fall. For one thing, it keeps their eyes from being jolted out of their head by their own weight.)
David Drake's Under the Hammer has a soldier badly injured by an explosion through his clamshell armor. "Goddamn armor musta' flexed." Some of his earlier works which take place during the Vietnam War, kind of address the "armor vs agility" question. (Drake served with the 11th Cav in Vietnam.) Some veterans don't wear the body armor because a) it's a hassle and b) they don't think it matters that much. If something's going to kill you, it will. Tank crew want the agility. Body armor won't protect you from burning up with the tank, but armor can slow down your escape from the tank.
Jerry Pournelle and S.M. Stirling's The Prince plays this correctly. Soldiers can be badly injured even if the combat armor isn't penetrated by a projectile. The armor is also no protection at all against a bayonet thrust.
In real life, body armor in the military is expected to reduce the severity of injuries, not prevent them completely. Minor wounds become bruises. Major wounds become minor wounds. Fatal wounds become major wounds. Only for projectiles hitting the armor, of course.
The choice made by the combat vets in Drake's work referenced above may be thinking even farther ahead. There's actually a small range of bodily injury where armor is useful. Some of those cases leave a quadriplegic instead of a corpse. This is not necessarily an attractive option.
Ace Of Scarabs: I had an idea about making a unique kind of bulletproofing protection in my own fiction - Nanogel. It is a nanotech mixture, made of purpose-specific nanites suspended in a thick gel substrate. The idea is that the nanogel has to be applied in a thick layer to work properly, but it is capable of stopping most ballistic weapons and is completely proof to shrapnel. Layers of nanogel combined with plate armor and silk/kevlar strips would be a nightmare to punch through without explosives or extra-high-energy ammunition. Would it be feasible?
Rogue 7: An anecdote about that first NCIS example, spoilered for safety- I started watching right as Gibbs got shot and apparently killed. I immediately wondered what exactly was playing that had Mark Harmon in it, because clearly Gibbs would not die like that.
