hon@hans.scs.carleton.ca (Edmund Hon) (02/14/91)
From: hon@hans.scs.carleton.ca (Edmund Hon)
A number of years ago I read an article saying that the US is developing
a kind of anti-tank missiles that does not require explosives - chemical
energy - but instead uses just kinetic energy to kill a tank, like the
depleted uranium AP rounds used on most modern tanks. It is a long, thin
missile, which flies at something like mach 2-3. Has anyone heard of this
missile? What is the status of this program now, canceled? Gone "black"?
--
/// _______________________________________________ . . o
/// /_ dmund |Coming to you from Spaceport | -O- . #-A .
/// /__/_/ |HongKong [T-00:00:15] | . . # H .
/// / /on |_<hon@hans.scs.carleton.ca>__|___________##/W\____john%ghostwheel.unm.edu@ariel.unm.edu (John Prentice) (02/15/91)
From: john%ghostwheel.unm.edu@ariel.unm.edu (John Prentice) In article <1991Feb13.220248.4292@cbnews.att.com> hon@hans.scs.carleton.ca (Edmund Hon) writes: >A number of years ago I read an article saying that the US is developing >a kind of anti-tank missiles that does not require explosives - chemical >energy - but instead uses just kinetic energy to kill a tank, like the >depleted uranium AP rounds used on most modern tanks. It is a long, thin >missile, which flies at something like mach 2-3. Has anyone heard of this >missile? What is the status of this program now, canceled? Gone "black"? We have used DU rounds fired from tanks for many years. However, the ones used currently are not hypervelocity (to my knowledge). The Defense Advanced Research Projects Agency has funded a program called the Armor/Anti-armor program for several years now to the tune of about $250 million a year to develop exotic armor and anti-armor (the program has about vanished I think now). A major thrust in that program has been developing hypervelocity impact weapons. Probably the most promising are spaced rods. These are just normal anti-armor DU rods (there are many other materials besides DU used), except they are cut up with the pieces spaced a bit apart from each other. The idea is that the shock wave from the impact does not travel up the rod and slow it down before it hits the armor. This is only important if the impact velocity is less than the sound speed of the rod (say 5 km/sec), but I no of nothing outside of the laboratory that can propel these projectiles that fast. There has been much work on using EM railguns for this purpose, but it is a long ways from a real weapon and I don't think they have ever been real successful anyway. I don't know of any "missiles" designed for this purpose, if by missile you mean something which is self propelled. However, my speciality is penetration mechanics, not ordinance, so it could be. If you are interested in more about this, go check out the Journal of Impact Engineering. There was an issue from three years ago or so that was devoted to the proceedings of an irregularly held meeting called the Hypervelocity Impact Symposium. However, that is mostly research info, it won't tell you much about actual weapons. By the way, I know of absolutely no effective anti-armor weapons which are not kinetic energy penetrators. Some use high explosives to get the kinetic energy (shaped charge jets for instance), but a chemical explosive is pretty useless direclty against armor. Also, most of these weapons do not kill by actually penetrating. Instead they set up a shock wave in the armor that spalls the inner surface and kills by fragmentation. It is no mean trick to actually penetrate armor all the way (though it can happen). John -- John K. Prentice john@unmfys.unm.edu (Internet) Dept. of Physics and Astronomy, University of New Mexico, Albuquerque, NM, USA Computational Physics Group, Amparo Corporation, Albuquerque, NM, USA
john%ghostwheel.unm.edu@ariel.unm.edu (John Prentice) (02/19/91)
From: john%ghostwheel.unm.edu@ariel.unm.edu (John Prentice) In article <1991Feb18.061318.14305@cbnews.att.com> lipm@midway.uchicago.edu (Everett Lipman) writes: > > >Although power supply size currently prevents EM railguns from being >used as practical weapons, there has been considerable progress >in railgun development over the past few years. There is active research >going on at military labs and also at University of Texas. For more info, >see the January '91 issue of IEEE TRANSACTIONS ON MAGNETICS, which has the >proceedings of a recent conference on railguns and related topics. > > True, it is a very active area, though the budget cutbacks now occuring are seriously impacting this area. However, it should be noted that power supplies are only one of the many problems with EM guns. More significant in some ways is the fact that most EM guns rip themselves up when they are fired and have to be carefully remachined before they can be used again. This was particularly true of rail guns where the rails would simply melt when the gun was fired. There has been progress on this problem, but it is not solved. Sandia has been working on using two stage light gas guns to inject a projectile into an EM gun. This avoids many of the problems of EM guns and, if I recall correctly, they have the world's record right now for the highest velocity yet obtained. The work I am personally aware of is aimed at doing equation of state research at extremely high temperatures and pressures. There is another group out there interested in lifting payloads into space with these systems. John -- John K. Prentice john@unmfys.unm.edu (Internet) Dept. of Physics and Astronomy, University of New Mexico, Albuquerque, NM, USA Computational Physics Group, Amparo Corporation, Albuquerque, NM, USA