tipmo@oak.circa.ufl.edu (01/21/91)
From: tipmo@oak.circa.ufl.edu Here's a question I've been wondering about. I know that sound waves can be quite destructive if focused/handled/played-with enough and I was wondering if the military has looked into this destructive capability. From my uneducated point of view, this looks like a VERY good weapon to use against ground troops, fortifications (perhaps) and especially fighter jets. Has anyone heard anything about this? ******************************************************************************* * Disclaimer: Some of these postings have been found to be an effective * * tool in the offending of the easily offended. So if you're one of * * them, do us both a favor, and don't read them! Thank you, and God * * Bless. * ******************************************************************************* *Internet: tipmo%maple.decnet@pine.circa.ufl.edu * *******************************************************************************
eacj@uunet.UU.NET (Julian Vrieslander) (01/22/91)
From: dartvax!batcomputer!eacj@uunet.UU.NET (Julian Vrieslander) I believe that there has indeed been work on techiques for generating human-lethal sound fields. I am not aware of any practical weapons that have come out of this research, and I think this is because there are some substantial obstacles and limitations to the proposed systems. One problem that I recall is that it is difficult or impossible to obtain a beam of acoustic energy that is sufficiently directional so that the personnel operating the weapons are not injured. -- Julian Vrieslander Neurobiology & Behavior, W250 Mudd Hall, Cornell University, Ithaca NY 14853 INTERNET: eacj@theory.tn.cornell.edu BITNET: eacj@crnlthry UUCP: ..cornell!batcomputer!eacj
jch@GS48.SP.CS.CMU.EDU (Jonathan Hardwick) (01/22/91)
From: Jonathan Hardwick <jch@GS48.SP.CS.CMU.EDU> This was investigated by the Germans towards the end of the Second World War, as part of their effort to knock allied bombers out of the sky. One prototype used a fuel-air mixture that was burnt (at great pressure) in the middle of a weird system of baffles, reflectors, etc, the aim being to achieve a beam of sound energy that could literally rip aircraft apart. They didn't get very far (hundreds of feet, I think), and I doubt if physics would allow current technology to be any improvement. Basically, the sound energy dissipates far too quickly to be useful -- you need some sort of "laser" effect to keep the beam collimated. Of course, other offensive uses of sound are possible, the most noteworthy recent example being the loud rock music played outside the Papal Nunciate (sp?) in an attempt to force Manuel Noriega out...
henry@zoo.toronto.edu (Henry Spencer) (01/22/91)
From: henry@zoo.toronto.edu (Henry Spencer) >From: tipmo@oak.circa.ufl.edu > ... I know that sound waves >can be quite destructive if focused/handled/played-with enough and I was >wondering if the military has looked into this destructive capability... Generating really high-power sound waves, and focussing them usefully, is relatively difficult. By far the easiest way to generate a powerful sound pulse is one that is already in use: detonate an explosive charge and let the blast wave do damage. -- If the Space Shuttle was the answer, | Henry Spencer at U of Toronto Zoology what was the question? | henry@zoo.toronto.edu utzoo!henry
phil@zorch.SF-Bay.ORG (Phil Gustafson) (01/23/91)
From: phil@zorch.SF-Bay.ORG (Phil Gustafson) The Scots have used sound as an offensive weapon for centuries. :-) -- | phil@zorch.SF-Bay.ORG | Phil Gustafson | {ames|pyramid|vsi1}!zorch!phil | UN*X/graphics consultant | sgi!gsi!phil | 1550 Martin Ave., San Jose CA 95126 | phil@gsi | 408/286-1749
cowie-james@CS.YALE.EDU (James Cowie) (01/23/91)
From: cowie-james@CS.YALE.EDU (James Cowie) In article <1991Jan22.021825.22248@cbnews.att.com> henry@zoo.toronto.edu (Henry Spencer) writes: >From: henry@zoo.toronto.edu (Henry Spencer) >>From: tipmo@oak.circa.ufl.edu >> ... I know that sound waves >>can be quite destructive if focused/handled/played-with enough and I was >>wondering if the military has looked into this destructive capability... > >Generating really high-power sound waves, and focussing them usefully, >is relatively difficult. I have a paper somewhere which was delivered to some professional organization of acoustical engineers on this topic. I could dig it out if anyone is really interested; it came from their journal many years ago. It is a humorous account of the US Army's research into tactical acoustics throughout WWII, by the guys who actually did the research. Generally, they came up with lots of toys which could "put a man into a mood to beat his wife" (their words) but nothing really applicable to warfare. Eventually they turned their attention to ways of effectively broadcasting propoganda from high-flying aircraft. --jim (cowie@yalecs) ----------------------------------------------------------------------
jjb%sequent.uucp@RELAY.CS.NET (Jeff Berkowitz) (01/23/91)
From: Jeff Berkowitz <jjb%sequent.uucp@RELAY.CS.NET> In article <1991Jan21.041118.5204@cbnews.att.com> tipmo@oak.circa.ufl.edu writes: > Here's a question I've been wondering about. I know that sound waves >can be quite destructive if focused/handled/played-with enough and I was >wondering if the military has looked into this destructive capability. Fighter and strike aircraft afterburners have been used as weapons on several occasions when bombs were deemed inappropriate. The example that I'm fairly certain of is the "Mayaguez" incident near Cambodia in 1975. Since they didn't want to bomb the ship, they had jets make passes at low altitude with full afterburners. As you note this can be incapacitating (or worse) for unprotected personnel. -- Jeff Berkowitz N6QOM uunet!sequent!jjb | Bugs are God's way of saying Sequent Computer Systems jjb@sequent.com | you have too much free time.
dvlssd@cs.umu.se (Stefan Skoglund) (01/24/91)
From: dvlssd@cs.umu.se (Stefan Skoglund) During the 50's and early 60's the USAF had some research on nuclear-driven bombers and cruise-missiles. The projects were stopped because of problem with basing, radiation and so on. The cruise missile was supposed to work like this : One small reactor as a heat source in a RAM-engine. A magazine with hydrogen bombs. Controlling equipment for the reactor. Terrain-following-radar controlled autopilot. Some boosters to get speed before you start the main engine. Let the missile fly at about 100 m above the ground in mach 5. then it gets into russia toss one bomb at Novosibirsk moscow and so one. Then the magazine is empty crash the missile in peking. Can you imagine how it would have looked. Only the sound would have killed everybody in the missiles path. And then we have the radiation to. The project stumbled then they got to think on one thing : there on earth shall we testfly the damn thing. The engine had already been tested and rated as satisfactory. Stefan Skoglund , dvlssd@cs.umu.se ps flame me in swedish. ds
jgd@Dixie.Com (John G. DeArmond) (01/24/91)
From: jgd@Dixie.Com (John G. DeArmond) >From: henry@zoo.toronto.edu (Henry Spencer) >>From: tipmo@oak.circa.ufl.edu >> ... I know that sound waves >>can be quite destructive if focused/handled/played-with enough and I was >>wondering if the military has looked into this destructive capability... As a matter of fact, they have. When the sound gets loud enough, we call it overpressure. Overpressure is effeciently developed by FAE or nukes. John -- John De Armond, WD4OQC | "Purveyors of speed to the Trade" (tm) Rapid Deployment System, Inc. | Home of the Nidgets (tm) Marietta, Ga | {emory,uunet}!rsiatl!jgd |"Politically InCorrect.. And damn proud of it
brooksp@hpcc01.corp.hp.com (Peter Brooks) (01/24/91)
From: Peter Brooks <brooksp@hpcc01.corp.hp.com> This was tried in the '60s. One of the main problems for anti-personnel use is that its really low frequencies that do damage, and it's almost impossible to get them to beam. (Maybe if you used a crater like the radio-telescope in Puerto Rico...) Another problem is that the low frewuencies are difficult to shield against, which makes it difficult to use this against an enemy without destroying the equipment, not to mention the crew..... BTW, I saw a picture of the speaker cone they used; it was pretty awesome. I think its cutoff frequency was something below the range of hearing for the human ear. Pete Brooks
rubin@cis.ohio-state.edu (daniel j rubin) (01/24/91)
From: rubin@cis.ohio-state.edu (daniel j rubin) >From: henry@zoo.toronto.edu (Henry Spencer) >>From: tipmo@oak.circa.ufl.edu >> ... I know that sound waves >>can be quite destructive if focused/handled/played-with enough and I was >>wondering if the military has looked into this destructive capability... > >Generating really high-power sound waves, and focusing them usefully, >is relatively difficult. By far the easiest way to generate a powerful >sound pulse is one that is already in use: detonate an explosive charge >and let the blast wave do damage. >-- I always wondered why the US did not research sound waves for a blanket defense of the country ( maybe they have and it will not work with the present technology ). I would think that a super high power ultrasonic transducer array of some sort could be placed on top of very tall towers all across the nation in a grid with one every several miles. If there was a national nuclear or whatever attack these transducer would direct a powerful wave of ultrasonic sound upward with every one of the stations in phase with each other. This huge ultrasonic wave generated in the middle-atmosphere would break up any warheads, plane or whatever that was in the atmosphere directly over US territory. I would think this would be less expensive and more reliable than the Star Wars theory. I do not know enough about ultrasonic transducer to say whether or not this is possible but it could be researched if it is not possible now.... Just a thought... - Dan Rubin
eachus@aries.mitre.org (Robert I. Eachus) (01/27/91)
From: eachus@aries.mitre.org (Robert I. Eachus)
There is another efficient way to generate high overpressures, a
"sonic boom" from an aircraft. Of course, a supersonic plane at say 25,000
foot altitude doesn't do much on the ground, but some planes can fly
supersonic close to the ground. The F4 Phantom II used to have (among
other records) a closed course record of, I think, 1003 MPH flown
over a 3 mile closed course under 100 feet AGL!
The Phantom drinks fuel at a ridiculous rate on afterburners, but
I remember hearing of a few cases in Nam where a Phantom pilot would
do a low "brush clearing" pass at supersonic speeds over enemy
positions after dropping ordinance. Much more effective than Agent
Orange... :-)
--
Robert I. Eachus
Our troops will have the best possible support in the entire
world. And they will not be asked to fight with one hand tied behind
their back. President George Bush, January 16, 1991jep@cis.ohio-state.edu (James E. Prior) (02/04/91)
From: oink!jep@cis.ohio-state.edu (James E. Prior) In article <1991Jan24.044530.26622@cbnews.att.com> rubin@cis.ohio-state.edu (daniel j rubin) writes: ...>I would think that a super high power ultrasonic >transducer array of some sort could be placed on top of very tall towers all >across the nation in a grid with one every several miles. If there was a >national nuclear or whatever attack these transducer would direct a powerful >wave of ultrasonic sound upward with every one of the stations in phase >with each other. This huge ultrasonic wave generated in the middle-atmosphere >would break up any warheads, plane or whatever that was in the atmosphere >directly over US territory. > > - Dan Rubin Sound at high frequencies attenuates greatly over distance. The air would heat up. At best, rapid heating of the air by ultrasound would cause it to expand rapidly, i.e. boom. I list some data concerning absorption of sound in air from 56th Ed. of CRC's Handbook of Chemistry and Physics: The follow data refer only to the temperature 20C (68F). Ther were abstracted from an extensive compilation prepared by L.B.Evans and H.E.Bass. The entire report, Tables of Absorption and Velocity of Sound in Still Air at 68F (20C), AD-738 576 is available from National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Road, Springfield, Va. 22151 Frequency Absorption Absorption @ 0% Rel Hum @ 100% Rel Hum Hz dB/Km dB/Km 20 0.51 .01 40 1.07 .04 50 1.26 .06 63 1.43 .09 100 1.67 .22 200 1.84 .77 400 1.96 2.02 630 2.11 3.05 800 2.27 3.57 1250 2.82 4.59 2000 4.14 6.29 4000 8.84 13.58 6300 14.89 27.72 10000 26.28 63.49 12500 35.81 96.63 16000 52.15 154.90 20000 75.37 237.93 40000 267.01 884.28 63000 644.66 1973.62 80000 1032.14 2913.01 Note the extreme attenuation of high frequencies. Note how music, thunder, cars and gunshots sound more muffled and boomy the further away they are. This means that high frequency sound weapons must generate their sound close to their target. The loudest sound generators remain to be explosives. The trick remains to be placing them close to their targets. -- Jim Prior jep@oink osu-cis!n8emr!oink!jep N8KSM
dam@cs.glasgow.ac.uk (David Morning) (02/04/91)
From: David Morning <dam@cs.glasgow.ac.uk> In article <1991Jan23.043048.7118@cbnews.att.com> phil@zorch.SF-Bay.ORG (Phil Gustafson) writes: >The Scots have used sound as an offensive weapon for centuries. :-) ^^^^^^^^^^^^^^^^ Hey there! Now just a minute! I happen to LIKE bagpipe music and especially so at 12:01 a.m. on Jan. 1st when the tartan octopus is pulled from the dusty attic for its annual outing. Offensive weapon indeed! Huh! Dave. Well, I've got to stick up for my countries' musical(?) contribution to the world!
john%ghostwheel.unm.edu@ariel.unm.edu (John Prentice) (02/15/91)
From: john%ghostwheel.unm.edu@ariel.unm.edu (John Prentice) In article <1991Jan21.041118.5204@cbnews.att.com> tipmo@oak.circa.ufl.edu writes: > Here's a question I've been wondering about. I know that sound waves >can be quite destructive if focused/handled/played-with enough and I was >wondering if the military has looked into this destructive capability. From >my uneducated point of view, this looks like a VERY good weapon to use against >ground troops, fortifications (perhaps) and especially fighter jets. Has >anyone heard anything about this? I have never heard of such things, and I think I would have it they exist. Of course, you could argue that the air blast off an explosive is such a weapon, however it is not usually the air shock that kills, it is the fragmentation of the casing. The biggest problem with using focused sound waves is 1) focusing them and 2) shocks decay very rapidly. 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