We're the Military and Airpower Guys of Jonah Goldberg of National Review Online + a stray we found wandering around looking lost. All original material JHD, BHD, JR, WT, and KA 2003-2010 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html Sat, 24 Mar 2012 16:06:19 Z Movable Type 4.12 en Copyright 2012 http://www.rssboard.org/rss-specification WARNING-WARNING-WARNING-WARNING!!!! If you are easily bowled over by technogeeky jargon, just skip on down one. If high school physics broke your spirit, just keep on movin' on - if you think Superman comics are packed full of useful insights into how Newton's Laws and the Laws of Thermodynamics work... just keep on keepin' on! Still here? You'll like this. The Instapilot will like this. Anybody wanna argue the math? [N.B. - it was sent to me, I didn't work this out] We know the formula for kinetic energy is KE = ½mass x velocity2 . Now let's check in with... http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html Mon, 04 Oct 2004 18:12:51 -0600 It was designed to hit 'em and stay in 'em and knock 'em down - not so much because of the armor, but because they drugged themselves and were, well, perhaps just tougher, and the .38 wasn't doing enough damage to cause them to lose interest in dropping your intestines around your ankles. Same problem the Brits had in colonial warfare that caused them to go to the .455 round. Stopping power for non-wussy natives who were grumpy about exterior meddling in their affairs. Apparently euro-soldiers were wusses who would go, "Oh! My! I've been shot! I must sit down and rest." The natives were more like, "Izzat the best you got? Eat assegai, asshat!" Or, in the case of the Moros, bolo machete. http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7337 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7337 Tue, 05 Oct 2004 10:10:46 -0600 Wasn't the .45 designed to defeat the kind of simple armor the Moros wore? That was the line we got when I joined the Army.... http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7336 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7336 Tue, 05 Oct 2004 09:56:56 -0600 The other thing, since we're being pedantic, is that air resisteance when falling off the taller buildings. I'm not sure that they won't have hit terminal velocity. In more ways than one. http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7332 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7332 Tue, 05 Oct 2004 08:21:24 -0600 I once worked with someone who had, in an earlier life, participated in RAF weapons research. The conclusion reached was simple. Rate of fire is no substitute for weight of fire. You can fire enough .32 ACP from a full-auto Skorpion to total the ballistic energy of one round from an elephant gun, but it won't stop a charging elephant. http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7331 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7331 Tue, 05 Oct 2004 08:04:33 -0600 Good points, Beck. Of course, the .45 was developed for that purpose with that in mind, to not go through people, if possible. The example above also does not include a discussion of the attenuation curve as the bullet loses energy over range. Still - it is an illustrative example, ain't it. As for your falling out of bed analogy - not in my experience - if for no other reason than you've generalized the energy too much - there is a concentration of the impact energy. Both my father and I have been shot wearing flak vests. We agree it's far more analgous to having the Hulk hit you in the chest with a baseball bat than falling out of bed. In my father's case, it did result in broken ribs and the bullet penetrated, albeit just under the skin along the ribs. http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7325 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7325 Tue, 05 Oct 2004 05:57:21 -0600 One problem. The equations here are assuming that 100% of the energy from the bullet is transfered to the body. In fact, relatively little of it will be transfered, because the body just doesn't have enough stopping power. In the initial example of a single .45 bullet, you might actually get 100% energy transfer. For instance, if the person were wearing a bullet proof vest which succeeded in stopping the bullet (or at least slowing it down enough that it didn't exit out the back) then the force of impact would be exactly like that 1m fall out of bed. If a human body (say it was the hulk) actually stopped a bullet from an apache, then yes, it'd be accelerated backwards as though it had been dropped off a 40 story building, which, even though the bullet didn't pass through, would pretty much liquify any ordinary person. As it is, the bullet passes clean through, and only loses perhaps a few hundred Joules. Instead, I propose an alternate system. Let's say the human body is capable of stopping one .45 bullet's worth of energy before giving up & allowing the bullet to exit through the back (in reality, it'd probably take 2 or 3 people to stop a .45, especially if it avoided big bones, but we'll just use the 1 person idea for now). In that case, you could line up 1,626 terrorists, and with a single round from an Apache, you could puncture every single one of them. Now all we have to do is figure out how to get them to all line up! http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7321 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7321 Tue, 05 Oct 2004 02:23:43 -0600 Mark! Again you wander through! Well, look at it this way - if you want to have a military available for Democrat Presidents to use, we've got to take kind of a non-partisan approach to this. Ya can't just toss us out as thug Republican stooges every time the PIP (Party In Power) and have the rest study horticulture... Just a thought! You should hang around Police/Fire/Ambulance/Trauma Center locker rooms. Kinda goes with the territory! Trust me - if you are going to have an army, it's better to have one that has some idea of what it's doing... then you don't find yourself having to kill children with car bombs to express your displeasure with the regime change... http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7319 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7319 Mon, 04 Oct 2004 22:40:47 -0600 Scientific Sickness! A 10 on the ouie gooie geek meter. http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7316 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7316 Mon, 04 Oct 2004 22:24:52 -0600 ... and the 120mm APFSDS long-rod penetrator fired from an Abrams has more than 10x the energy of the A-10's 30mm. Cheers JMH http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7315 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7315 Mon, 04 Oct 2004 22:03:56 -0600 Now, for fun (and I sho wisht I wuz good wit nummers), imagine how much energy is released at the point of impact from a few dozen 25mm rounds from an AC-130 circling at 15K feet overhead. Or how it must REALLY suck to be on the incoming end of the 40mm, and especially that ass-kicking 105!!! The only thing I think must be more fun to watch/use are the miniguns in the MH-53 Pave Lows and the MH-60 Pave Hawks. What they may lack in size, they more than make up for in street-clearing, stump-grinding rpms! SangerM http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7314 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7314 Mon, 04 Oct 2004 21:09:21 -0600 Wow. I just love when science explains the effects of high-velocity/large calibre ammo on things. Now lets do the math for that anti-personel tank round that John was talking about. (At least I think that it was talked about here...) http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7312 http://www.thedonovan.com/archives/2004/10/extrasuper_serious_geek_alert.html#comment-7312 Mon, 04 Oct 2004 19:59:12 -0600