Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!sdd.hp.com!caen!news.cs.indiana.edu!att!cbnews!cbnews!military From: JEWELLLW@VM.CC.PURDUE.EDU (Larry W. Jewell) Newsgroups: sci.military Subject: About those Ugly M-60's Message-ID: <1991Feb5.043146.6128@cbnews.att.com> Date: 5 Feb 91 04:31:46 GMT Sender: military@cbnews.att.com (William B. Thacker) Organization: AT&T Bell Laboratories Lines: 100 Approved: military@att.att.com From: "Larry W. Jewell" ----------------------------------------------------------------------- One nice thing about discribing something poorly is that you get more answers than you could have hoped for otherwise. Both views below are interesting in that they represent differing philosophies about "add-on" armour. I still think I would prefer a nice cozy 17 inches of hard plate (Go "Big Mo"!). ------------------------------------------------------------------------ In article <1991Jan28.041718.10532@cbnews.att.com> you write: > > >From: "Larry W. Jewell" >Footage from Sandy Arabia shown M-60's with large flat plates attached >to the turret. Is this reactive armour? Any idea how it works and how >much confidence the tankers have in it? I've seen T-72's with smaller, >and much more numerous boxes attached to the turret. Is this difference >demanded by the rounder shape of a "T" or is it Soviet thinking? > Larry, A few answers... 1) Is this reactive armor? -Yes 2) Reactive armor is basically just blocks of explosive attached to the tank. It works by disrupting the hot gas jet put out by a HEAT (High Explosive Anti Tank) round. These rounds work by exploding a shaped charge about a foot away from the armor, which forms a very thin, superhot gas jet which then burns through the tank's armor. (This is the reason HEAT rounds and antitank missiles such as the TOW have a foot long spike on the front-to get correct standoff distance for the jet formation. But I digress...) The idea behind reactive armor is to disrupt this jet as it forms by exploding a charge as the HEAT warhead goes off. The jet, to use language from my real job, is "very susceptable to initial conditions" Disrupting it even a little bit vastly reduces its effectiveness. On average, you can expect reactive armor to halve the penetration ability of a given HEAT round. The M60 series desperately needs the additional armor protection. The M1 series' Chobham armor is especially designed to defeat HEAT rounds, which is why you don't see it attached to the M1s. Reactive armor has started a whole new mini arms race. The TOW IIA has a small explosive charge in front of the main one, to set off the reactive armor before jet formation. I've been told that the Soviets now have countermeasures to this, .... Reactive armor is a godsend to tankers in another way. Back when the Sagger came out, people began to predict the demise of the tank from the proliferation of cheap antitank guided missiles. However, reactive armor has now cast great doubts on the ability of these ATGMs, all armed with HEAT warheads, to kill modern tanks equipped with it. However, RA does nothing to stop a sabot round, the tank's main anti tank round, so tanks again become the premiere anti tank weapon.... (A sabot round is basical- ly just a big bullet- no explosive at all.) 3) How much confidence do tankers have in it? I can't speak for all my brethren, but I'll lie, cheat and steal to get it on my M60A3 if I get called up... 4) I don't know why the Soviets have many small blocks compared to our few large ones. I'll ask around- someone at my unit might know... Hope this helps.. -- Eric R. | "Any quantity of interest can be found by solving edremy@d31ha2.Stanford.EDU | the Schrodinger equation of the system. The Chemistry Dept, Stanford U | solution is left as an exercise for the reader." ======================================================================== 7 From: "Nicholas C. Hester" Date: Wed, 30 Jan 91 16:47:00 EST I'm sure others have sent you letters already, but just in case, the large flat plates are applique armor. This is simply extra armor welded in place. >From what I have gathered, it is to add thickness to certain area, enhancing protection. There was an extensive discussion of this on sci.military in the past few months. Alas, Bill has no FTP account to reach archived material. Applique is different than reactive armor where the round is pre-detonated or the blast force is retarded by the shaped charge of the reactive armor. Anti- tank missiles get around this by a penetrator rod that pre-detonates the charge. Hope this helps. Nicholas C. Hester | | ia80024@Maine.Bitnet | Farhvergnugen: "I've fallen, and I can't get up" | ia80024@Maine.Maine.edu | | ************************************************************************ *The world will never have lasting peace so long as men reserve for war* *the finest human qualities. * *********************** John Foster Dulles ***************************** Larry W. Jewell JEWELLLW@VM.CC.PURDUE.EDU